Exploring the Potential Applications of the Noninvasive Reporter Gene RUBY in Plant Genetic Transformation

Betalains can be conveniently observed and quantified and, accordingly, have the potential as naked-eye visual screening reporters during plant transformation. RUBY is a new reporter system that uses “2A” peptides to fuse three key genes, CYP76AD1, DODA, and glucosyl transferase, for betalain biosynthesis, and has been successfully used for transformation of rice, Arabidopsis, and cotton, but its potential applications in the genetic transformation of various other plant species remain to be verified. In this study, RUBY was transferred into the hairy roots of Plukenetia volubilis and Nicotiana benthamiana, and was transferred into Arabidopsis by the floral-dip method. The expression levels of CYP76AD1, DODA, and glucosyl transferase were detected by RT−PCR and RT−qPCR, the relationship between the expression level of RUBY and red coloration was analyzed, and the genetic stability of RUBY in transgenic Arabidopsis was studied. The results showed that the expression of RUBY could reconstruct the betalain biosynthesis pathway in the hairy roots of P. volubilis, N. benthamiana, and Arabidopsis plants, indicating that it has the potential for versatile use across species. As a reporter, betalain did not affect callus induction, plant regeneration, development, or fertility. However, when used in plant transformation for observation and visual screening, it needed to accumulate to a certain extent to show red coloration, and it was positively correlated with gene expression. In general, RUBY is a convenient reporter for plant transformation, and has no obvious side effects during plant growth and development. However, the potential application of RUBY for visual screening is highly determined by the expression level, and further improvement is needed.

Transcriptome-Based Construction of the Gibberellin Metabolism and Signaling Pathways in Eucalyptus grandis × E. urophylla, and Functional Characterization of GA20ox and GA2ox in Regulating Plant Development and Abiotic Stress Adaptations

Gibberellins (GAs) are the key regulators controlling plant growth, wood production and the stress responses in perennial woody plants. The role of GA in regulating the above-mentioned processes in Eucalyptus remain largely unclear. There is still a lack of systematic identification and functional characterization of GA-related genes in Eucalyptus. In this study, a total of 59,948 expressed genes were identified from the major vegetative tissues of the E. grandis × E. urophylla using transcriptome sequencing. Then, the key gene families in each step of GA biosynthesis, degradation and signaling were investigated and compared with those of Arabidopsis, rice, and Populus. The expression profile generated using Real-time quantitative PCR showed that most of these genes exhibited diverse expression patterns in different vegetative organs and in response to abiotic stresses. Furthermore, we selectively overexpressed EguGA20ox1, EguGA20ox2 and EguGA2ox1 in both Arabidopsis and Eucalyptus via Agrobacterium tumefaciens or A. rhizogenes-mediated transformation. Though both Arabidopsis EguGA20ox1- and EguGA20ox2-overexpressing (OE) lines exhibited better vegetative growth performance, they were more sensitive to abiotic stress, unlike EguGA2ox1-OE plants, which exhibited enhanced stress resistance. Moreover, overexpression of EguGA20ox in Eucalyptus roots caused significantly accelerated hairy root initiation and elongation and improved root xylem differentiation. Our study provided a comprehensive and systematic study of the genes of the GA metabolism and signaling and identified the role of GA20ox and GA2ox in regulating plant growth, stress tolerance, and xylem development in Eucalyptus; this could benefit molecular breeding for obtaining high-yield and stress-resistant Eucalyptus cultivars.

Genome-Wide Identification and Expression Analysis of Cytokinin Response Regulator (RR) Genes in the Woody Plant Jatropha curcas and Functional Analysis of JcRR12 in Arabidopsis

The cytokinin (CK) response regulator (RR) gene family plays a pivotal role in regulating the developmental and environmental responses of plants. Axillary bud outgrowth in the perennial woody plant Jatropha curcas is regulated by the crosstalk between CK and gibberellins (GA). In this study, we first analyzed the effects of gibberellin A3 (GA3), lovastatin (a CK synthesis inhibitor), decapitation, and their interaction, on the outgrowth of axillary buds. The results indicate that lovastatin completely inhibited GA-promoted axillary bud outgrowth and partially weakened the decapitation-promoted axillary bud outgrowth. To further characterize and understand the role of CK signaling in promoting the development of female flowers and branches, we performed bioinformatics and expression analyses to characterize the CK RR gene (JcRR) family in J. curcas. A total of 14 members of the JcRR family were identified; these genes were distributed on 10 chromosomes. Phylogenetic analysis indicated that the corresponding RR proteins are evolutionarily conserved across different plant species, and the Myb-like DNA-binding domain divides the 14 members of the JcRR family into type-A and type-B proteins. Further analysis of cis-acting elements in the promoter regions of JcRRs suggests that JcRRs are expressed in response to phytohormones, light, and abiotic stress factors; thus, JcRRs may be involved in some plant development processes. Genomic sequence comparison revealed that segmental duplication may have played crucial roles in the expansion of the JcRR gene family, and five pairs of duplicated genes were all subjected to purifying selection. By analyzing RNA sequencing (RNA-seq) and quantitative reverse transcription-polymerase chain reaction (qRT–PCR) data, we characterized that the temporospatial expression patterns of JcRRs during the development of various tissues and the response of these genes to phytohormones and abiotic stress. The JcRRs were mainly expressed in the roots, while they also exhibited differential expression patterns in other tissues. The expression levels of all six type-A and one type-B JcRRs increased in response to 6-benzylaminopurine (6-BA), while the four type-B JcRRs levels decreased. The expression levels of two type-B JcRRs increased in response to exogenous GA3 treatment, while those of three type-A and three type-B JcRRs decreased. We found that type-A JcRRs may play a positive role in the continuous growth of axillary buds, while the role of type-B JcRRs might be the opposite. In response to abiotic stress, the expression levels of two type-A and three type-B JcRRs strongly increased. The overexpression of JcRR12 in Arabidopsis thaliana slightly increased the numbers of rosette branches after decapitation, but not under normal conditions. In conclusion, our results provide detailed knowledge of JcRRs for further analysis of CK signaling and JcRR functions in J. curcas.

An ortholog of the MADS-box gene SEPALLATA3 regulates stamen development in the woody plant Jatropha curcas

Macadamia germplasm and genomic database (MacadamiaGGD): A comprehensive platform for germplasm innovation and functional genomics in Macadamia

As an important nut crop species, macadamia continues to gain increased amounts of attention worldwide. Nevertheless, with the vast increase in macadamia omic data, it is becoming difficult for researchers to effectively process and utilize the information. In this work, we developed the first integrated germplasm and genomic database for macadamia (MacadamiaGGD), which includes five genomes of four species; three chloroplast and mitochondrial genomes; genome annotations; transcriptomic data for three macadamia varieties, germplasm data for four species and 262 main varieties; nine genetic linkage maps; and 35 single-nucleotide polymorphisms (SNPs). The database serves as a valuable collection of simple sequence repeat (SSR) markers, including both markers that are based on macadamia genomic sequences and developed in this study and markers developed previously. MacadamiaGGD is also integrated with multiple bioinformatic tools, such as search, JBrowse, BLAST, primer designer, sequence fetch, enrichment analysis, multiple sequence alignment, genome alignment, and gene homology annotation, which allows users to conveniently analyze their data of interest. MacadamiaGGD is freely available online (http://MacadamiaGGD.net). We believe that the database and additional information of the SSR markers can help scientists better understand the genomic sequence information of macadamia and further facilitate molecular breeding efforts of this species.

Efficiency of graft-transmitted JcFT for floral induction in woody perennial species of the Jatropha genus depends on transport distance

Abstract Flowering Locus T (FT) promotes flowering by integrating six genetic pathways. In Arabidopsis, the FT protein is transported from leaves to shoot apices and induces flowering. However, contradictory conclusions about floral induction via graft-transmitted FT in trees were reported in previous studies. We obtained extremely early-flowering transgenic woody Jatropha curcas by overexpression of J. curcas FT using Arabidopsis thaliana SUC2 promoter (SUC2:JcFT) and non-flowering transgenic J. curcas by RNA interference (RNAi), which were used to investigate the function of graft-transmitted JcFT in floral induction in woody perennials. Scions from five wild-type species of the Jatropha genus and from JcFT-RNAi transgenic J. curcas were grafted onto SUC2:JcFT rootstocks. Most grafted plants produced flowers in 1–2 months, and the flowering percentage and frequency of various grafted plants decreased with increasing scion length. Consistently, FT protein abundance in scions also decreased with increasing distance from graft junctions to the buds. These findings suggest that FT proteins can be transmitted by grafting and can induce the floral transition in woody perennials, and the efficiency of graft-transmitted JcFT for floral induction depends on the scion length, which may help explain previous seemingly contradictory observations regarding floral induction via graft-transmitted FT in trees.

Extended mining of the oil biosynthesis pathway in biofuel plant Jatropha curcas by combined analysis of transcriptome and gene interactome data

Abstract Background Jatropha curcas L. is an important non-edible oilseed crop with a promising future in biodiesel production. However, little is known about the molecular biology of oil biosynthesis in this plant when compared with other established oilseed crops, resulting in the absence of agronomically improved varieties of Jatropha. To extensively discover the potentially novel genes and pathways associated with the oil biosynthesis in J. curcas, new strategy other than homology alignment is on the demand. Results In this study, we proposed a multi-step computational framework that integrates transcriptome and gene interactome data to predict functional pathways in non-model organisms in an extended process, and applied it to study oil biosynthesis pathway in J. curcas. Using homologous mapping against Arabidopsis and transcriptome profile analysis, we first constructed protein–protein interaction (PPI) and co-expression networks in J. curcas. Then, using the homologs of Arabidopsis oil-biosynthesis-related genes as seeds, we respectively applied two algorithm models, random walk with restart (RWR) in PPI network and negative binomial distribution (NBD) in co-expression network, to further extend oil-biosynthesis-related pathways and genes in J. curcas. At last, using k-nearest neighbors (KNN) algorithm, the predicted genes were further classified into different sub-pathways according to their possible functional roles. Conclusions Our method exhibited a highly efficient way of mining the extended oil biosynthesis pathway of J. curcas. Overall, 27 novel oil-biosynthesis-related gene candidates were predicted and further assigned to 5 sub-pathways. These findings can help better understanding of the oil biosynthesis pathway of J. curcas, as well as paving the way for the following J. curcas breeding application.

Selection and Validation of Reference Genes for qRT-PCR Analysis in the Oil-Rich Tuber Crop Tiger Nut (Cyperus esculentus) Based on Transcriptome Data

Tiger nut (Cyperus esculentus), a perennial C4 plant of the Cyperaceae family, is an unconventional crop that is distinguished by its oil-rich tubers, which also possesses the advantages of strong resistance, wide adaptability, short life periods, and large biomass. To facilitate studies on gene expression in this species, we identified and validated a series of reference genes (RGs) based on transcriptome data, which can be employed as internal controls for qRT-PCR analysis in tiger nut. Fourteen putative candidate RGs were identified and evaluated across nine different tissues of two cultivars, and the RGs were analyzed using three different algorithms (geNorm, NormFinder, and BestKeeper). The stability rankings of the candidate RGs were merged into consensus lists with RankAggreg. For the below-ground storage organ of tiger nut, the optimal RGs were TUB4 and UCE2 in different developmental stages of tubers. UCE2 and UBL5 were the most stably expressed RGs among all tissues, while Rubisco and PGK exhibited the lowest expression stability. UCE2, UBL5 and Rubisco were compared to normalize the expression levels of the caleosin (CLO) and diacylglycerol acyltransferase 2-2 (DGAT2-2) genes across the same tissues. Our results showed that the RGs identified in this study, which exhibit more uniform expression patterns, may be utilized for the normalization of qRT-PCR results, promoting further research on gene expression in various tissues of tiger nut.

First Report of Collar Rot in Purple Passion Fruit (Passiflora edulis) Caused by Neocosmospora solani in Yunnan province, China

Purple passion fruit (Passiflora edulis Sims) is a perennial climbing vine native to South America that is grown worldwide as an edible tropical fruit with excellent nutritional value and high economic value (Zibadi et al. 2007). With the increasing expansion of the plantation area in China, considerable economic loss caused by collar rot has attracted wide attention. From 2018-2020, collar rot resulted in the death of many plants of P. edulis 'Mantianxing', a commercial cultivar in China, in southwest China's Yunnan province. The disease spread quickly, and field incidence reached more than 50%. Stem rot symptoms were observed at the base of the stem, about 5-10 cm from the ground, resulting in wilting, defoliation, and death of plants. Representative symptomatic samples were collected from the base of five plants, surface disinfested for 30 seconds with 75% ethanol and 15 min with 10% hypochlorite, washed three times with sterile distilled water, then transferred to potato dextrose agar (PDA) dishes. After 2 days in the dark at 28℃, emerging fungal colonies were purified on new PDA dishes cultured at 28℃ for 7 days. The mycelia were flocculent. The color of the surface and the reverse colony was white and cream, respectively. On synthetic nutrient agar (SNA) medium, microconidia were oval, ellipsoidal or reniform, 0- or 1-septate, and 6.7-23.1 μm in length (n>30); macroconidia were straight to slightly curved, 3- or 5-septate, and 30.8-53.9 μm in length (n>30). Genomic DNA, extracted from six isolates, was amplified with three pairs of primers, ITS1 and ITS4 (White et al. 1990) , EF1-728F and EF1-986R (Carbone and Kohn 1999), and fRPB2-5F and fRPB2-7cR (Liu et al. 1999). The amplicons from all six isolates were sequenced and identical sequences obtained. The sequence of one representative isolate was uploaded to NCBI (National Center for Biotechnology Information) and analyzed with BLASTn in the Fusarium MLST database (https://fusarium.mycobank.org). The sequence of the internal transcribed spacer 1 (ITS1) region (GenBank MN944550) showed 99.1% (449/453 bp) identity to Fusarium solani strain NRRL 53667 (syn: Neocosmospora solani, GenBank MH582405). The sequence of the translation elongation factor-1 (EF-1) gene (GenBank MN938933) showed 97.8% identity (263/269 bp) to F. solani strain NRRL 32828 (GenBank DQ247135). The sequence of the second largest subunit of RNA polymerase Ⅱ (RPB2) gene (GenBank MW002686) showed 98.7% identity (810/821 bp) to F. solani strain NRRL 43441 (GenBank MH582407). Based on a multilocus phylogenetic analysis of the ITS1, EF-1 and RPB2 sequences, coupled with the morphological characteristics, the isolate (designated as NsPed1) was considered to be Neocosmospora solani (syn: Fusarium solani) (Crespo et al. 2019). Subsequently, three-month-old healthy seedlings and 45-day-old cuttings of P. edulis 'Mantianxing' plants were inoculated with the isolate NsPed1 to test its pathogenicity. Stems were wounded, approximately 1-2 mm deep, in the collar region of plants at 2 cm above the soil. A disk (9 mm in diameter) of NsPed1-colonized PDA was placed on the wound. Sterile PDA served as controls. All plants were kept in a growth chamber with 28-30°C, 60% relative humidity, and 16/8-h light/dark photoperiod. Fifteen plants were used for each treatment and replicated three times. Two weeks after inoculation, the stems of the inoculated plants turned brown with a lesion, 2-5 cm in length, and the leaves wilted. These symptoms were similar to those of the diseased plants in the field. The control plants were asymptomatic. N. solani NsPed1 was re-isolated from the infected plants, satisfying Koch’s postulates. Taken together, N. solani NsPed1 was identified as the causal pathogen of collar rot in P. edulis 'Mantianxing'. Knowledge of the causal organism of collar rot in purple passion fruit will lead to improved measures to prevent and control the disease in China and other countries.

First Report of Collar Rot in Purple Passion Fruit (Passiflora edulis) Caused by Neocosmospora solani in Yunnan province, China

Purple passion fruit (Passiflora edulis Sims) is a perennial climbing vine native to South America that is grown worldwide as an edible tropical fruit with excellent nutritional value and high economic value (Zibadi et al. 2007). With the increasing expansion of the plantation area in China, considerable economic loss caused by collar rot has attracted wide attention. From 2018-2020, collar rot resulted in the death of many plants of P. edulis 'Mantianxing', a commercial cultivar in China, in southwest China's Yunnan province. The disease spread quickly, and field incidence reached more than 50%. Stem rot symptoms were observed at the base of the stem, about 5-10 cm from the ground, resulting in wilting, defoliation, and death of plants. Representative symptomatic samples were collected from the base of five plants, surface disinfested for 30 seconds with 75% ethanol and 15 min with 10% hypochlorite, washed three times with sterile distilled water, then transferred to potato dextrose agar (PDA) dishes. After 2 days in the dark at 28℃, emerging fungal colonies were purified on new PDA dishes cultured at 28℃ for 7 days. The mycelia were flocculent. The color of the surface and the reverse colony was white and cream, respectively. On synthetic nutrient agar (SNA) medium, microconidia were oval, ellipsoidal or reniform, 0- or 1-septate, and 6.7-23.1 μm in length (n>30); macroconidia were straight to slightly curved, 3- or 5-septate, and 30.8-53.9 μm in length (n>30). Genomic DNA, extracted from six isolates, was amplified with three pairs of primers, ITS1 and ITS4 (White et al. 1990) , EF1-728F and EF1-986R (Carbone and Kohn 1999), and fRPB2-5F and fRPB2-7cR (Liu et al. 1999). The amplicons from all six isolates were sequenced and identical sequences obtained. The sequence of one representative isolate was uploaded to NCBI (National Center for Biotechnology Information) and analyzed with BLASTn in the Fusarium MLST database (https://fusarium.mycobank.org). The sequence of the internal transcribed spacer 1 (ITS1) region (GenBank MN944550) showed 99.1% (449/453 bp) identity to Fusarium solani strain NRRL 53667 (syn: Neocosmospora solani, GenBank MH582405). The sequence of the translation elongation factor-1 (EF-1) gene (GenBank MN938933) showed 97.8% identity (263/269 bp) to F. solani strain NRRL 32828 (GenBank DQ247135). The sequence of the second largest subunit of RNA polymerase Ⅱ (RPB2) gene (GenBank MW002686) showed 98.7% identity (810/821 bp) to F. solani strain NRRL 43441 (GenBank MH582407). Based on a multilocus phylogenetic analysis of the ITS1, EF-1 and RPB2 sequences, coupled with the morphological characteristics, the isolate (designated as NsPed1) was considered to be Neocosmospora solani (syn: Fusarium solani) (Crespo et al. 2019). Subsequently, three-month-old healthy seedlings and 45-day-old cuttings of P. edulis 'Mantianxing' plants were inoculated with the isolate NsPed1 to test its pathogenicity. Stems were wounded, approximately 1-2 mm deep, in the collar region of plants at 2 cm above the soil. A disk (9 mm in diameter) of NsPed1-colonized PDA was placed on the wound. Sterile PDA served as controls. All plants were kept in a growth chamber with 28-30°C, 60% relative humidity, and 16/8-h light/dark photoperiod. Fifteen plants were used for each treatment and replicated three times. Two weeks after inoculation, the stems of the inoculated plants turned brown with a lesion, 2-5 cm in length, and the leaves wilted. These symptoms were similar to those of the diseased plants in the field. The control plants were asymptomatic. N. solani NsPed1 was re-isolated from the infected plants, satisfying Koch’s postulates. Taken together, N. solani NsPed1 was identified as the causal pathogen of collar rot in P. edulis 'Mantianxing'. Knowledge of the causal organism of collar rot in purple passion fruit will lead to improved measures to prevent and control the disease in China and other countries.

Overexpression of Type 1 and 2 Diacylglycerol Acyltransferase Genes (JcDGAT1 and JcDGAT2) Enhances Oil Production in the Woody Perennial Biofuel Plant Jatropha curcas

Diacylglycerol acyltransferase (DGAT) is the only enzyme that catalyzes the acyl-CoA-dependent acylation of sn-1, 2-diacylglycerol (DAG) to form triacylglycerol (TAG). The two main types of DGAT enzymes in the woody perennial biofuel plant Jatropha curcas, JcDGAT1 and JcDGAT2, were previously characterized only in heterologous systems. In this study, we investigated the functions of JcDGAT1 and JcDGAT2 in J. curcas.JcDGAT1 and JcDGAT2 were found to be predominantly expressed during the late stages of J. curcas seed development, in which large amounts of oil accumulated. As expected, overexpression of JcDGAT1 or JcDGAT2 under the control of the CaMV35S promoter gave rise to an increase in seed kernel oil production, reaching a content of 53.7% and 55.7% of the seed kernel dry weight, respectively, which were respectively 25% and 29.6% higher than that of control plants. The increase in seed oil content was accompanied by decreases in the contents of protein and soluble sugars in the seeds. Simultaneously, there was a two- to four-fold higher leaf TAG content in transgenic plants than in control plants. Moreover, by analysis of the fatty acid (FA) profiles, we found that JcDGAT1 and JcDGAT2 had the same substrate specificity with preferences for C18:2 in seed TAGs, and C16:0, C18:0, and C18:1 in leaf TAGs. Therefore, our study confirms the important role of JcDGAT1 and JcDGAT2 in regulating oil production in J. curcas.

Overexpression of Type 1 and 2 Diacylglycerol Acyltransferase Genes (JcDGAT1 and JcDGAT2) Enhances Oil Production in the Woody Perennial Biofuel Plant Jatropha curcas

Diacylglycerol acyltransferase (DGAT) is the only enzyme that catalyzes the acyl-CoA-dependent acylation of sn-1, 2-diacylglycerol (DAG) to form triacylglycerol (TAG). The two main types of DGAT enzymes in the woody perennial biofuel plant Jatropha curcas, JcDGAT1 and JcDGAT2, were previously characterized only in heterologous systems. In this study, we investigated the functions of JcDGAT1 and JcDGAT2 in J. curcas.JcDGAT1 and JcDGAT2 were found to be predominantly expressed during the late stages of J. curcas seed development, in which large amounts of oil accumulated. As expected, overexpression of JcDGAT1 or JcDGAT2 under the control of the CaMV35S promoter gave rise to an increase in seed kernel oil production, reaching a content of 53.7% and 55.7% of the seed kernel dry weight, respectively, which were respectively 25% and 29.6% higher than that of control plants. The increase in seed oil content was accompanied by decreases in the contents of protein and soluble sugars in the seeds. Simultaneously, there was a two- to four-fold higher leaf TAG content in transgenic plants than in control plants. Moreover, by analysis of the fatty acid (FA) profiles, we found that JcDGAT1 and JcDGAT2 had the same substrate specificity with preferences for C18:2 in seed TAGs, and C16:0, C18:0, and C18:1 in leaf TAGs. Therefore, our study confirms the important role of JcDGAT1 and JcDGAT2 in regulating oil production in J. curcas.

Selection and Validation of Reference Genes for qRT-PCR Analysis in the Oil-Rich Tuber Crop Tiger Nut (Cyperus esculentus) Based on Transcriptome Data

Tiger nut (Cyperus esculentus), a perennial C4 plant of the Cyperaceae family, is an unconventional crop that is distinguished by its oil-rich tubers, which also possesses the advantages of strong resistance, wide adaptability, short life periods, and large biomass. To facilitate studies on gene expression in this species, we identified and validated a series of reference genes (RGs) based on transcriptome data, which can be employed as internal controls for qRT-PCR analysis in tiger nut. Fourteen putative candidate RGs were identified and evaluated across nine different tissues of two cultivars, and the RGs were analyzed using three different algorithms (geNorm, NormFinder, and BestKeeper). The stability rankings of the candidate RGs were merged into consensus lists with RankAggreg. For the below-ground storage organ of tiger nut, the optimal RGs were TUB4 and UCE2 in different developmental stages of tubers. UCE2 and UBL5 were the most stably expressed RGs among all tissues, while Rubisco and PGK exhibited the lowest expression stability. UCE2, UBL5 and Rubisco were compared to normalize the expression levels of the caleosin (CLO) and diacylglycerol acyltransferase 2-2 (DGAT2-2) genes across the same tissues. Our results showed that the RGs identified in this study, which exhibit more uniform expression patterns, may be utilized for the normalization of qRT-PCR results, promoting further research on gene expression in various tissues of tiger nut.

超量表达JcSEUSS1 基因促进小桐子叶中花青素的合成. Over-expression of JcSEUSS1 from Jatropha curcas Induces the Accumulation of Anthocyanin in Leaves.

Developmental basis for flower sex determination and effects of cytokinin on sex determination in Plukenetia volubilis (Euphorbiaceae)

Comparative transcriptome analysis of gynoecious and monoecious inflorescences reveals regulators involved in male flower development in the woody perennial plant Jatropha curcas

Flower-Specific Overproduction of Cytokinins Altered Flower Development and Sex Expression in the Perennial Woody Plant Jatropha curcas L.

Jatropha curcas L. is monoecious with a low female-to-male ratio, which is one of the factors restricting its seed yield. Because the phytohormone cytokinins play an essential role in flower development, particularly pistil development, in this study, we elevated the cytokinin levels in J. curcas flowers through transgenic expression of a cytokinin biosynthetic gene (AtIPT4) from Arabidopsis under the control of a J. curcas orthologue of TOMATO MADS BOX GENE 6 (JcTM6) promoter that is predominantly active in flowers. As expected, the levels of six cytokinin species in the inflorescences were elevated, and flower development was modified without any alterations in vegetative growth. In the transgenic J. curcas plants, the flower number per inflorescence was significantly increased, and most flowers were pistil-predominantly bisexual, i.e., the flowers had a huge pistil surrounded with small stamens. Unfortunately, both the male and the bisexual flowers of transgenic J. curcas were infertile, which might have resulted from the continuously high expression of the transgene during flower development. However, the number and position of floral organs in the transgenic flowers were well defined, which suggested that the determinacy of the floral meristem was not affected. These results suggest that fine-tuning the endogenous cytokinins can increase the flower number and the female-to-male ratio in J. curcas.

Supporting data for "De novo genome assembly and Hi-C analysis reveal the association between chromatin architecture alterations and sex differentiation in the woody plant Jatropha curcas"

De novo genome assembly and Hi-C analysis reveal the association between chromatin architecture alterations and sex differentiation in the woody plant Jatropha curcas

Background: Chromatin architecture is an essential factor regulating gene transcription in different cell types and developmental phases. However, studies on chromatin architecture in perennial woody plants and on the function of chromatin organization in sex determination have not been reported. Results: Here, we produced a chromosome-scale de novo assembly of the woody plant Jatropha curcas genome with a total length of 379.5 Mb and a scaffold N50 of 30.7 Mb using PacBio long reads combined with genome-wide chromosome conformation capture (Hi-C) technology. Based on this high-quality reference genome, we detected chromatin architecture differences between monoecious and gynoecious inflorescence buds of Jatropha. Differentially expressed genes (DEGs) were significantly enriched in the changed A/B compartments and topologically associated domain (TAD) regions and occurred preferentially in differential contact regions between monoecious and gynoecious inflorescence buds. Twelve DEGs related to flower development or hormone synthesis displayed significantly different genomic interaction patterns in monoecious and gynoecious inflorescence buds. These results demonstrate that chromatin organization participates in the regulation of gene transcription during the process of sex differentiation in Jatropha. Conclusions: We have revealed the features of chromatin architecture in perennial woody plants and investigated the possible function of chromatin organization in Jatropha sex differentiation. These findings will facilitate understanding of the regulatory mechanisms of sex determination in higher plants.

Jatropha curcas ortholog of tomato MADS-box gene 6 (JcTM6) promoter exhibits floral-specific activity in Arabidopsis thaliana

Background Jatropha curcas L., a perennial oilseed plant, is considered as a promising feedstock for biodiesel production. Genetic modification of flowering characteristics is critical for Jatropha breeding. However, analysis of floral-specific promoters in Jatropha is limited. Methods In this study, we isolated the Jatropha ortholog of TM6 (JcTM6) gene from Jatropha flower cDNA library and detected the expression pattern of JcTM6 gene by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). We isolated a 1.8-kb fragment from the 5’ region of the JcTM6 gene and evaluated its spatiotemporal expression pattern in Arabidopsis using the β-glucuronidase (GUS) reporter gene and Arabidopsis ATP/ADP isopentenyltransferase 4 (AtIPT4) gene, respectively. Results JcTM6 was identified as a flower-specific gene in Jatropha. As expected, JcTM6 promoter was only active in transgenic Arabidopsis flowers with the strongest activity in stamens. Moreover, JcTM6:AtIPT4 transgenic Arabidopsis showed a phenotype of large flowers without any alterations in other organs. Furthermore, deletion of the region from –1,717 to –876 bp resulted in the disappearance of promoter activity in stamens but an increase in promoter activity in young leaves, sepals, and petals. Deletion analysis suggests that the –1,717- to –876-bp promoter fragment contains regulatory elements that confer promoter activity in stamens and inhibit activity in young leaves, sepals, and petals.

Silencing of the Ortholog of DEFECTIVE IN ANTHER DEHISCENCE 1 Gene in the Woody Perennial Jatropha curcas Alters Flower and Fruit Development

DEFECTIVE IN ANTHER DEHISCENCE 1 (DAD1), a phospholipase A1, utilizes galactolipids (18:3) to generate α-linolenic acid (ALA) in the initial step of jasmonic acid (JA) biosynthesis in Arabidopsis thaliana. In this study, we isolated the JcDAD1 gene, an ortholog of Arabidopsis DAD1 in Jatropha curcas, and found that it is mainly expressed in the stems, roots, and male flowers of Jatropha. JcDAD1-RNAi transgenic plants with low endogenous jasmonate levels in inflorescences exhibited more and larger flowers, as well as a few abortive female flowers, although anther and pollen development were normal. In addition, fruit number was increased and the seed size, weight, and oil contents were reduced in the transgenic Jatropha plants. These results indicate that JcDAD1 regulates the development of flowers and fruits through the JA biosynthesis pathway, but does not alter androecium development in Jatropha. These findings strengthen our understanding of the roles of JA and DAD1 in the regulation of floral development in woody perennial plants.

星油藤转录组简单重复序列特征分析及其分子标记开发. Characteristic Analysis of Simple Sequence Repeat Sequences and Development of Molecular Markers Based on Plukenetia volubilis Transcriptome

Construction of A Mutant Library and Screening of Mutants Induced by Fast-Neutron Irradiation in Plukenetia volubilis L.

Plukenetia volubilis is a perennial woody oilseed vine, which belongs to Euphorbiaceae family. Seed oil of P. volubilis is rich in polyunsaturated fatty acids, especially the α-linolenic acid, which accounts for 44.2%-50.8%. Therefore, P. volubilis has the great potential to be an ideal feed stock for production of oil with a high nutritional value. However, P. volubilis still suffers from mortal diseases caused by Fusarium oxysporum, which considerably hinder the widely exploitation and utilization of products from P. volubilis. At present, it is difficult to breed new variety by traditional cross-breeding because of rare germplasm resources. Therefore, it is urgent to obtain new germplasm resources of P. volubilis. In this study, seeds of P. volubilis were irradiated with fast neutron (FN) for creating new germplasm. Firstly, the effects of different dose of fast neutron on seedling survival rates of the plants were investigated to determine the semi-lethal dose, which will be applied to construct the P. volubilis mutant library. The agronomic and other biological traits of the M1 plants were investigated. The results showed that: (1) The semi-lethal radiation dose of FN on P. volubilis seeds is approximately 47.6 Gy; (2) The M1 seedlings induced by fast-neutron radiation grew abnormally; (3) FN induces a range of abnormal phenotypes in P. volubilis, accounted for 9.2% of M1 surviving plants; (4) Five mutants were identified by random amplified polymorphic DNA (RAPD) analysis; (5) The fruit size of mutant 3A423 was significantly increased, and the average weight of its seed was 1.8-fold heavier than that of the wild-type (WT) plants. Thus, mutant 3A423 is an excellent candidate parent for breeding high-yielding P. volubilis. Taken together, these mutants obtained in this study will be useful for further research of genetic breeding and functional genomics of P. volubilis.

JCDB: a comprehensive knowledge base for Jatropha curcas, an emerging model for woody energy plants

Background Jatropha curcas is an oil-bearing plant, and has seeds with high oil content (~ 40%). Several advantages, such as easy genetic transformation and short generation duration, have led to the emergence of J. curcas as a model for woody energy plants. With the development of high-throughput sequencing, the genome of Jatropha curcas has been sequenced by different groups and a mass of transcriptome data was released. How to integrate and analyze these omics data is crucial for functional genomics research on J. curcas. Results By establishing pipelines for processing novel gene identification, gene function annotation, and gene network construction, we systematically integrated and analyzed a series of J. curcas transcriptome data. Based on these data, we constructed a J. curcas database (JCDB), which not only includes general gene information, gene functional annotation, gene interaction networks, and gene expression matrices but also provides tools for browsing, searching, and downloading data, as well as online BLAST, the JBrowse genome browser, ID conversion, heatmaps, and gene network analysis tools. Conclusions JCDB is the most comprehensive and well annotated knowledge base for J. curcas. We believe it will make a valuable contribution to the functional genomics study of J. curcas. The database is accessible at http://jcdb.xtbg.ac.cn.

Identification and Expression Analysis of WOX Family Genes in Sacha Inchi (Plukenetia volubilis)

In this study, nine members of the PvoWOX gene family were identified by local BLAST from transcriptome and genome database of Sacha Inchi (Plukenetia volubilis). The basic information such as molecular weight, protein size, and isoelectric point of PvoWOX members was analyzed by bioinformatics method. The phylogenetic tree of PvoWOX is categorized into three clades, including WUS, intermediate, and ancient clade. Furthermore, the gene structure and the conserved domains of proteins of PvoWOX family members were analyzed, and was found to be conserved in the same evolution clade. All members of PvoWOX contain conserved homeodomain, and the members of the WUS clade contain the WUS-box domain. The expression patterns of PvoWOX members were analysis by transcriptome and qRT-PCR analysis. The results showed that the nine PvoWOX genes exhibited different expression patterns in different organs of P. volubilis and the expression of the members of WUS clade and intermediate clade was tissue-specific, while the members of ancient clade were expressed in all organs. The expression patterns of PvoWOX members suggested that the different gene members might have experienced a functional divergence. This study will be helpful for further studies of PvoWOX functions in the growth and development of P. volubilis.

快中子辐射星油藤突变体库的构建及其突变体筛选

星油藤(Plukenetia volubilis L.)是大戟科(Euphorbiaceae)多年生木质藤本油料植物，其种子油富含多 不饱和脂肪酸，其中α-亚麻酸含量高达44.2%~50.8%，被认为是开发高营养价值保健食用油的理想原料之一。但星油藤易感染由尖孢镰刀菌引起的致死性根茎基腐病，严重限制了其推广种植。且因国内星油藤品种资源单一，无法采用传统的杂交育种方法获得抗病高产的新品种。因此，星油藤研究中的当务之急是创制新的种质资源。本研究采用快中子辐射诱变星油藤种子进行新种质创制。首先探索了不同快中子辐射剂量对星油藤成苗率的影响，以确定半致死剂量。然后采用半致死剂量快中子辐射星油藤种子构建突变体库，对M1 代植株的生物学及其农艺性状进行观测分析。结果表明：(1)星油藤种子的快中子辐射半致死剂量约为47.6 Gy；(2)快中子辐射抑制了星油藤M1 代幼苗生长；(3)快中子辐射的星油藤植株表型变异类型丰富，具有肉眼可见表型变异的植株占M1 代存活株的9.2%；(4)采用随机扩增多态性DNA 技术(Random Amplified Polymorphic DNA, RAPD)鉴定了5 株具有扩增产物多态性的突变株; (5)变异株3A423 果实显著增大，种子单粒重是野生型的1.8 倍，是培育高产品种的优良植株。本研究获得的突变体材料将有助于星油藤遗传育种和功能基因组学的进一步研究。

First Report of Powdery Mildew in Jatropha curcas Caused by Erysiphe quercicola in Yunnan province, China

Jatropha curcas L. is a potential biofuel crop due to the high oil content found in its seeds (Laviola et al., 2017). Since 2016, a powdery mildew disease has been observed on J. curcas leaves in Xishuangbanna Tropical Botanical Garden (XTBG) in Yunnan province, China. Early symptoms on seedlings of J. curcas was irregular white patches, and later the powdery layers covered the whole leaves, petioles, and stems. The infection caused premature drop of leaves. Microscopic observation showed that hyphae are straight to flexuous, hyaline, thin-walled, septate, 4 to 7 μm wide. Hyphal appressoria are simply lobed to multi-lobed in opposite pairs. Conidiophores erect, 61 to 150 × 5 to 8 μm. Foot-cells erect or curved at the base, 29 to 82 × 4 to 7 μm, followed by 1 to 3 shorter cells, forming non-catenate type of conidia, the basal septum of foot-cells usually formed 3 to 19 μm above the junction with the mycelial mother cell. Conidia ellipsoid to doliiform, without fibrosin bodies, but with one big vacuole or several small vacuoles. Primary conidia obovoid-ellipsoid, with the apex rounded and the base subtruncate, 23 to 39 × 12 to 22 μm, length/width ratio 1.3 to 2.5 (mostly ≤ 2); secondary conidia doliiform when mature, ends truncate or subtruncate, 27 to 38 × 12 to 17 μm, length/width ratio 1.9 to 2.5 (mostly ≥ 2). Germ tubes lobed or longitubus pattern and produced in perihilar or apical position, short to long, without swollen tips. Chasmothecia were not found in the collected samples. The voucher specimen was deposited at the herbarium of XTBG (HITBC), Chinese Academy of Sciences under accession no. F000001. The genomic DNA from mycelium and conidia collected from J. curcas leaves was extracted and amplified the internal transcribed spacer (ITS) and 28S rDNA sequences with primer pairs ITS1/ITS4 and LSU1/LSU2, respectively (Scholin et al., 1994, White et al., 1990). A 645-bp ITS and 582-bp 28S rDNA sequences (GenBank accession No. KY865729 and MK430430) were obtained, showing ˃ 99.8% identity with both Erysiphe quercicola on Quercus mongolica (KY700706 and KY797320) and Oidium heveae on Hevea brasiliensis (KJ868176 and KJ868175), respectively. Analysis of both morphology and sequence identity suggests that the pathogen is Erysiphe quercicola S. Takam. & U. Braun, a powdery mildew fungus, which is parasitic on Q. mongolica in China (Liyanage et al., 2016). According to the Koch’s postulates (Falkow, 1988), a diseased leaf was gently pressed onto leaves of three-week-old healthy J. curcas seedlings grown in separate pots to test the pathogenicity of E. quercicola. Inoculated plants were cultured in a greenhouse at 28/25℃ (day/night) at 14/10-h light/dark photoperiod and 70% relative humidity. After six days, the inoculated leaves displayed the similar symptoms that appeared in the original diseased plants, and after 12 days, the inoculated leaves began to drop; whereas no similar symptoms were observed in the control plants. The pathogenicity test was carried out twice with similar results. Microscopic observation showed that the fungus isolated from the inoculated leaves was identical to the original pathogen. To our knowledge, this study is the first report that the powdery mildew caused by E. quercicola occurred on J. curcas in Yunnan province, China, which is also being a serious problem in J. curcas plantation worldwide.

Ectopic Expression of Jatropha curcas TREHALOSE-6-PHOSPHATE PHOSPHATASE J Causes Late-Flowering and Heterostylous Phenotypes in Arabidopsis but not in Jatropha

Trehalose-6-phosphate (T6P) phosphatase (TPP), a dephosphorylating enzyme, catalyzes the dephosphorylation of T6P, generating trehalose. In Jatropha, we found six members of the TPP family. Five of them JcTPPA, JcTPPC, JcTPPD, JcTPPG, and JcTPPJ are highly expressed in female flowers or male flowers, or both, suggesting that members of the JcTPP family may participate in flower development in Jatropha. The wide expression of JcTPPJ gene in various organs implied its versatile roles and thus was chosen for unraveling its biological functions during developmental process. We constructed an overexpression vector of JcTPPJ cDNA driven by the cauliflower mosaic virus (CaMV) 35S promoter for genetic transformation. Compared with control Arabidopsis plants, 35S:JcTPPJ transgenic Arabidopsis plants presented greater sucrose contents in their inflorescences and displayed late-flowering and heterostylous phenotypes. Exogenous application of sucrose to the inflorescence buds of wild-type Arabidopsis repressed the development of the perianth and filaments, with a phenocopy of the 35S:JcTPPJ transgenic Arabidopsis. These results suggested that the significantly increased sucrose level in the inflorescence caused (or induced) by JcTTPJ overexpression, was responsible for the formation of heterostylous flower phenotype. However, 35S:JcTPPJ transgenic Jatropha displayed no obvious phenotypic changes, implying that JcTPPJ alone may not be sufficient for regulating flower development in Jatropha. Our results are helpful for understanding the function of TPPs, which may regulate flower organ development by manipulating the sucrose status in plants.

Identification and expression analysis of cytokinin metabolic genes IPTs, CYP735A and CKXs in the biofuel plant Jatropha curcas

The seed oil of Jatropha curcas is considered a potential bioenergy source that could replace fossil fuels. However, the seed yield of Jatropha is low and has yet to be improved. We previously reported that exogenous cytokinin treatment increased the seed yield of Jatropha. Cytokinin levels are directly regulated by isopentenyl transferase (IPT), cytochrome P450 monooxygenase, family 735, subfamily A (CYP735A), and cytokinin oxidase/dehydrogenase (CKX). In this study, we cloned six IPT genes, one JcCYP735A gene, and seven JcCKX genes. The expression patterns of these 14 genes in various organs were determined using real-time quantitative PCR. JcIPT1 was primarily expressed in roots and seeds, JcIPT2 was expressed in roots, apical meristems, and mature leaves, JcIPT3 was expressed in stems and mature leaves, JcIPT5 was expressed in roots and mature leaves, JcIPT6 was expressed in seeds at 10 days after pollination, and JcIPT9 was expressed in mature leaves. JcCYP735A was mainly expressed in roots, flower buds, and seeds. The seven JcCKX genes also showed different expression patterns in different organs of Jatropha. In addition, CK levels were detected in flower buds and seeds at different stages of development. The concentration of N6-(Δ2-isopentenyl)-adenine (iP), iP-riboside, and trans-zeatin (tZ) increased with flower development, and the concentration of iP decreased with seed development, while that of tZ increased. We further analyzed the function of JcCYP735A using the CRISPR-Cas9 system, and found that the concentrations of tZ and tZ-riboside decreased significantly in the Jccyp735a mutants, which showed severely retarded growth. These findings will be helpful for further studies of the functions of cytokinin metabolic genes and understanding the roles of cytokinins in Jatropha growth and development.

Over-expression of JcTPS1 from Jatropha curcas Induces Early Flowering of Arabidopsis and Improves Anthocyanin Accumulation in Leaves

miR172 regulates both vegetative and reproductive development in the perennial woody plant Jatropha curcas

Gibberellin Inhibits Floral Initiation in the Perennial Woody Plant Jatropha curcas

De novo transcriptome assembly and comparative analysis between male and benzyladenine-induced female inflorescence buds of Plukenetia volubilis

The complete chloroplast genome sequence of the biofuel plant Sacha Inchi, Plukenetia volubilis

De novo transcriptome assembly of the eight major organs of Sacha Inchi (Plukenetia volubilis) and the identification of genes involved in α-linolenic acid metabolism

Comparative chloroplast genomics and phylogenetics of nine Lindera species (Lauraceae)

超量表达小桐子JcTPS1 促进拟南芥开花并增加叶片花青素含量

开花是高等植物生长和发育过程中最重要的阶段。在体内发育调控信号和适当的环境因子共同作用下，植物个体由营养生长向生殖生长转变，启动开花进程。碳水化合物在植物成花转变过程中具有重要的调控作用，而六磷酸海藻糖(trehalose-6-phosphate, T6P)的含量是反映植物体内碳水化合物含量水平的重要指标。本研究克隆了能源植物小桐子(Jatropha curcas)的六磷酸海藻糖合成酶(trehalose-6-phosphate synthase 1, JcTPS1)基因，在拟南芥中进行超量表达，对其功能进行初步研究。超量表达JcTPS1 的转基因拟南芥提前开花。此外，超量表达JcTPS1 可以诱导拟南芥花青素合成的关键酶基因二氢黄酮醇-4- 还原酶 (dihydroflavonol-4-reductase, AtDFR)和无色花青素双加氧酶(leucoanthocyanidin dioxygenase, AtLDOX)上调表达，从而显著促进花青素在叶片中的积累。研究结果表明，小桐子JcTPS1 基因可能在植物开花和花青素合成过程中起重要的调控作用。

Manipulation of Auxin Response Factor 19 affects seed size in the woody perennial Jatropha curcas

Overexpression of Jatropha Gibberellin 2-oxidase 6 (JcGA2ox6) Induces Dwarfism and Smaller Leaves, Flowers and Fruits in Arabidopsis and Jatropha

Comparative transcriptome analysis of axillary buds in response to the shoot branching regulators gibberellin A3 and 6-benzyladenine in Jatropha curcas

Three TFL1 homologues regulate floral initiation in the biofuel plant Jatropha curcas

Comparative Transcriptome Analysis between Gynoecious and Monoecious Plants Identifies Regulatory Networks Controlling Sex Determination in Jatropha curcas

Establishment of in vitro regeneration system of woody oil crop Plukenetia volubilis

Isolation and characterization of the Jatropha curcas APETALA1 (JcAP1) promoter conferring preferential expression in inflorescence buds

Thidiazuron increases fruit number in the biofuel plant Jatropha curcas by promoting pistil development

An ortholog of LEAFY in Jatropha curcas regulates flowering time and floral organ development

Ectopic expression ofJatropha curcas APETALA1(JcAP1) caused early flowering in Arabidopsis, but not in Jatropha

Jatropha curcasis a promising feedstock for biofuel production because Jatropha oil is highly suitable for the production of biodiesel and bio-jet fuels. However, Jatropha exhibits a low seed yield as a result of unreliable and poor flowering.APETALA1(AP1) is a floral meristem and organ identity gene in higher plants. The flower meristem identity genes of Jatropha have not yet been identified or characterized. To better understand the genetic control of flowering in Jatropha, anAP1homolog (JcAP1) was isolated from Jatropha. An amino acid sequence analysis of JcAP1 revealed a high similarity to the AP1 proteins of other perennial plants.JcAP1was expressed in inflorescence buds, flower buds, sepals and petals. The highest expression level was observed during the early developmental stage of the flower buds. The overexpression ofJcAP1using the cauliflower mosaic virus (CaMV) 35S promoter resulted in extremely early flowering and abnormal flowers in transgenic Arabidopsis plants. Several flowering genes downstream ofAP1were up-regulated in theJcAP1-overexpressing transgenic plant lines. Furthermore,JcAP1overexpression rescued the phenotype caused by the Arabidopsis AP1 loss-of-function mutantap1-11. Therefore,JcAP1is an ortholog ofAtAP1,which plays a similar role in the regulation of flowering in Arabidopsis. However, the overexpression ofJcAP1in Jatropha using the same promoter resulted in little variation in the flowering time and floral organs, indicating thatJcAP1may be insufficient to regulate flowering by itself in Jatropha. This study helps to elucidate the function ofJcAP1and contributes to the understanding of the molecular mechanisms of flower development in Jatropha.

Identification and characterization of tetraploid and octoploid Jatropha curcas induced by colchicine

Subcellular Localization of Rice Small G Protein OsRab5b in BY-2 Cells

To investigate the subcellular localization of rice OsRab5b and the Gly2 role in the protein subcellular localization. OsRab5b-GFP and OsRab5b（Gly2Ala）-GFP plasmids were transformed into BY-2 cells. The laser confocal microscope was employed to observe the transgenic cells treated with drugs, a marker protein VSRAt-1 or an endocytosis tracer dye FM4-64. Results showed Punctuate and diffuse signals were observed in the OsRab5b-GFP transgenic cells. Wortmannin at a concentration of 16.5 μmol/L led to the change of the OsRab5b-GFP marked organelles into small vacuoles. The signals of OsRab5b-GFP were aggregated after the treatment of Brefeldin A（BFA）at a concentration of 100 μg/mL, but not at 10 μg/mL. Most of the OsRab5b-GFP positive signals colocalized with the VSRAt-1 positive organelles in the cells with and without wortmannin or BFA treatment. Additionally, most of the OsRab5b-GFP marked organelles colocalized with the endosomal marker FM4-64 after 60-min incubation. The diffuse signals of the mutation protein OsRab5b（Gly2Ala）-GFP were observed in the nuclei and cytoplasm of the transgenic cells, which were not affected by the wortmannin or BFA treatment. OsRab5b is localized to the prevacuolar compartment of BY-2 cells and the Gly2 site is essential for the correct subcellular localization of OsRab5b.

Identification and Characterization of the FT/TFL1 Gene Family in the Biofuel Plant Jatropha curcas

An efficient protocol for Agrobacterium-mediated transformation of the biofuel plant Jatropha curcas by optimizing kanamycin concentration and duration of delayed selection

Gibberellin Promotes Shoot Branching in the Perennial Woody Plant Jatropha curcas

Isolation and characterization of an ubiquitin extension protein gene (JcUEP) promoter from Jatropha curcas

Characterization of genes involved in gibberellin metabolism and signaling pathway in the biofuel plant Jatropha curcas

Selection of Reliable Reference Genes for Gene Expression Studies of a Promising Oilseed Crop, Plukenetia volubilis, by Real-Time Quantitative PCR

A promoter analysis of MOTHER OF FT AND TFL1 1 (JcMFT1), a seed-preferential gene from the biofuel plant Jatropha curcas

Transcriptome of the inflorescence meristems of the biofuel plant Jatropha curcas treated with cytokinin

Benzyladenine treatment promotes floral feminization and fruiting in a promising oilseed crop Plukenetia volubilis

Isolation and functional characterization of JcFT, a FLOWERING LOCUS T (FT) homologous gene from the biofuel plant Jatropha curcas

Analysis of the transcriptional responses in inflorescence buds of Jatropha curcas exposed to cytokinin treatment

Determination of oil contents in Sacha inchi (Plukenetia volubilis) seeds at different developmental stages by two methods: Soxhlet extraction and time-domain nuclear magnetic resonance

Effects of soil-applied paclobutrazol on the vegetative and reproductive growth of biofuel plant Jatropha curcas

Ectopic Overexpression of an AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) Gene OsIAA4 in Rice Induces Morphological Changes and Reduces Responsiveness to Auxin

Erratum to: Dehydroascorbate reductase and glutathione reductase play an important role in scavenging hydrogen peroxide during natural and artificial dehydration of Jatropha curcas seeds

Identification and differential expression of two dehydrin cDNAs during maturation of Jatropha curcas seeds

Selection of Reliable Reference Genes for Gene Expression Studies in the Biofuel Plant Jatropha curcas Using Real-Time Quantitative PCR

Dehydroascorbate reductase and glutathione reductase play an important role in scavenging hydrogen peroxide during natural and artificial dehydration of Jatropha curcas seeds

The Characterization of SaPIN2b, a Plant Trichome-Localized Proteinase Inhibitor from Solanum americanum

Identification and expression analysis of two small heat shock protein cDNAs from developing seeds of biodiesel feedstock plant Jatropha curcas

Improved expression and purification of recombinant human serum albumin from transgenic tobacco suspension culture

Analysis of expressed sequence tags from biodiesel plant Jatropha curcas embryos at different developmental stages

Benzyladenine Treatment Significantly Increases the Seed Yield of the Biofuel Plant Jatropha curcas

The reversed terminator of octopine synthase gene on the Agrobacterium Ti plasmid has a weak promoter activity in prokaryotes

Agrobacterium tumefaciens-mediated transformation of biofuel plant Jatropha curcas using kanamycin selection

Vacuolar sorting receptors (VSRs) and secretory carrier membrane proteins (SCAMPs) are essential for pollen tube growth

Cloning, expression and wounding induction of β-caryophyllene synthase gene from Mikania micrantha H.B.K. and allelopathic potential of β-caryophyllene

Characterization of the Sesbania rostrata Phytochelatin Synthase Gene: Alternative Splicing and Function of Four Isoforms

A 64 kDa sucrose binding protein is membrane-associated and tonoplast-localized in developing mung bean seeds

Culture of Escherichia coli in SOC medium improves the cloning efficiency of toxic protein genes

Overexpression of a Weed (Solanum americanum) Proteinase Inhibitor in Transgenic Tobacco Results in Increased Glandular Trichome Density and Enhanced Resistance to Helicoverpa armigera and Spodoptera litura

Production and characterization of soluble human lysosomal enzyme α-iduronidase with high activity from culture media of transgenic tobacco BY-2 cells

Sensitivity of Jatropha curcas seeds to (60)Co-gamma radiation and their medial lethal doses in radiation breeding

Using silica particles to isolate total RNA from plant tissues recalcitrant to extraction in guanidine thiocyanate

The most commonly used protocol of the RNA isolation, the guanidine thiocyanate method, was unsuitable for recalcitrant plant tissues containing a large amount of storage proteins and secondary metabolites. We demonstrated that RNA could bind to the silica particles, which have been used successfully in DNA isolation from various sources, under a high concentration of NaCl in the presence of ethanol and sodium acetate. Based on this observation, an efficient, inexpensive, and highly reproducible technique, the acid phenol-silica method, was developed to isolate high-quality RNAs from various plant tissues recalcitrant to extraction in guanidine thiocyanate.

Genome sequence and characterization of a new virus infecting Mikania micrantha H.B.K.

PLANT BIOREACTORS FOR PHARMACEUTICALS

Oil contents and fatty acid composition in Jatropha curcas seeds collected from different regions

Characterization and in vitro mineralization function of a soluble protein complex P60 from the nacre of Pinctada fucata

Efficient and rapid non-test tube cloning of Jatropha curcas

Purification and characterization of native and recombinant SaPIN2a, a plant sieve element-localized proteinase inhibitor

Chloroplast-Like Organelles Were Found in Enucleate Sieve Elements of Transgenic Plants Overexpressing a Proteinase Inhibitor

The Nightshade Proteinase Inhibitor IIb Gene is Constitutively Expressed in Glandular Trichomes

Cloning and Characterization of an RNase-Related Protein Gene Preferentially Expressed in Rice Stems

Identification of cis-elements for ethylene and circadian regulation of the Solanum melongena gene encoding cysteine proteinase

The Expression of Tomato 1-Aminocyclopropane-1-Carboxylate Synthase in Escherichia coli

Genetic Analysis and Molecular Characterization of the GIP Binding Protein Alpha-subunit Gene from Rice Dwarf Mutant dwarf 69

Inhibition of endogenous trypsin- and chymotrypsin-like activities in transgenic lettuce expressing heterogeneous proteinase inhibitor SaPIN2a

Two genes encoding protein phosphatase 2A catalytic subunits are differentially expressed in rice

G-box binding coincides with increased Solanum melongena cysteine proteinase expression in senescent fruits and circadian-regulated leaves

Proteinase inhibitor II from Solanum americanum, molecular characterization and potential use in generating insect-resistant transgenic vegetables

A proteinase inhibitor II of Solanum americanum is expressed in phloem

Physico-chemical parameters influencing DNase activity of the cyanobacterium Spirulina platensis

Studies on the sensitivity of Spirulina platensis to antibiotics and herbicide: relationship with selectable markers for genetic transformation

A simple and efficient protocol for isolation of high molecular weight DNA from the Cyanobacterium Spirulina platensis

Integration and expression of Human growth hormone gene in Caladium bicolor

Comparison of Seed Storage Proteins Between Ordinary and Purple Pericarp Rice (Oryza sativa L.)