Publications of NIPGR Scientists
Permanent URI for this communityhttps://ndkr-library.nipgr.ac.in/handle/123456789/1
Browse
8 results
Search Results
Item The R2R3-MYB-SG7 transcription factor CaMYB39 orchestrates surface phenylpropanoid metabolism and pathogen resistance in chickpea(John Wiley & Sons, 2023) Saxena, Samiksha; Pal, Lalita; Naik, Jogindra; Singh, Yeshveer; Verma, Praveen K.; Chattopadhyay, Debasis; Pandey, AshutoshFlavonoids are important plant pigments and defense compounds; understanding the transcriptional regulation of flavonoid biosynthesis may enable engineering crops with improved nutrition and stress tolerance. Here, we characterize R2R3-MYB domain subgroup 7 transcription factor CaMYB39, which regulates flavonol biosynthesis primarily in chickpea trichomes. CaMYB39 overexpression in chickpea was accompanied by a change in flux availability for the phenylpropanoid pathway, particularly flavonol biosynthesis. Lines overexpressing CaMYB39 showed higher isoflavonoid levels, suggesting its role in regulating isoflavonoid pathway. CaMYB39 transactivates the transcription of early flavonoid biosynthetic genes (EBG). FLAVONOL SYNTHASE2, an EBG, encodes an enzyme with higher substrate specificity for dihydrokaempferol than other dihydroflavonols explaining the preferential accumulation of kaempferol derivatives as prominent flavonols in chickpea. Interestingly, CaMYB39 overexpression increased trichome density and enhanced accumulation of diverse flavonol derivatives in trichome-rich tissues. Moreover, CaMYB39 overexpression reduced ROS levels and induced defense gene expression which aids in partially blocking the penetration efficiency of the fungal pathogen, Ascochyta rabiei, resulting in lesser symptoms, thus establishing its role against deadly Ascochyta blight(AB) disease. Overall, our study reports an instance where R2R3-MYB-SG7 member, CaMYB39, besides regulating flavonol biosynthesis, modulates diverse pathways like general phenylpropanoid, isoflavonoid, trichome density and defense against necrotrophic fungal infection in chickpea.Item A chickpea genetic variation map based on the sequencing of 3,366 genomes(Springer Nature Publishing AG, 2021) Varshney, Rajeev K; Roorkiwal, Manish; Sun, Shuai; Bajaj, Prasad; Chitikineni, Annapurna; Thudi, Mahendar; Singh, Narendra P; Du, Xiao; Upadhyaya, Hari D; Khan, Aamir W; Wang, Yue; Garg, Vanika; Fan, Guangyi; Cowling, Wallace A; Crossa, José; Gentzbittel, Laurent; Voss-Fels, Kai Peter; Valluri, Vinod Kumar; Sinha, Pallavi; Singh, Vikas K; Ben, Cécile; Rathore, Abhishek; Punna, Ramu; Singh, Muneendra K; Tar'an, Bunyamin; Bharadwaj, Chellapilla; Yasin, Mohammad; Pithia, Motisagar S; Singh, Servejeet; Soren, Khela Ram; Kudapa, Himabindu; Jarquín, Diego; Cubry, Philippe; Hickey, Lee T; Dixit, Girish Prasad; Thuillet, Anne-Céline; Hamwieh, Aladdin; Kumar, Shiv; Deokar, Amit A; Chaturvedi, Sushil K; Francis, Aleena; Howard, Réka; Chattopadhyay, Debasis; Edwards, David; Lyons, Eric; Vigouroux, Yves; Hayes, Ben J; Wettberg, Eric von; Datta, Swapan K; Yang, Huanming; Nguyen, Henry T; Wang, Jian; Siddique, Kadambot H M; Mohapatra, Trilochan; Bennetzen, Jeffrey L; Xu, Xun; Liu, XinZero hunger and good health could be realized by 2030 through effective conservation, characterization and utilization of germplasm resources1. So far, few chickpea (Cicer arietinum) germplasm accessions have been characterized at the genome sequence level2. Here we present a detailed map of variation in 3,171 cultivated and 195 wild accessions to provide publicly available resources for chickpea genomics research and breeding. We constructed a chickpea pan-genome to describe genomic diversity across cultivated chickpea and its wild progenitor accessions. A divergence tree using genes present in around 80% of individuals in one species allowed us to estimate the divergence of Cicer over the last 21 million years. Our analysis found chromosomal segments and genes that show signatures of selection during domestication, migration and improvement. The chromosomal locations of deleterious mutations responsible for limited genetic diversity and decreased fitness were identified in elite germplasm. We identified superior haplotypes for improvement-related traits in landraces that can be introgressed into elite breeding lines through haplotype-based breeding, and found targets for purging deleterious alleles through genomics-assisted breeding and/or gene editing. Finally, we propose three crop breeding strategies based on genomic prediction to enhance crop productivity for 16 traits while avoiding the erosion of genetic diversity through optimal contribution selection (OCS)-based pre-breeding. The predicted performance for 100-seed weight, an important yield-related trait, increased by up to 23% and 12% with OCS- and haplotype-based genomic approaches, respectively.Item A repeat length variation in myo-inositol monophosphatase gene contributes to seed size trait in chickpea(Nature Publishing Group, 2017) Dwivedi, Vikas; Parida, Swarup K.; Chattopadhyay, DebasisChickpea (Cicer arietinum L.) is the third most important food legume crop. Seed size is the most economically important trait for chickpea. To understand the genetic regulation of seed size in chickpea, the present study established a three-way association of CT repeat length variation of a simple sequence repeat (SSR) in myo-inositol monophosphatase gene (CaIMP) with seed weight and phytic acid content by large scale validation and genotyping in a set of genetically diverse germplasm accessions and two reciprocal intra-specific mapping populations. Germplasms and mapping individuals with CT repeat-length expansion in the 5' untranslated region of CaIMP exhibited a pronounced increase in CaIMP protein level, enzymatic activity, seed-phytate content and seed weight. A chickpea transient expression system demonstrated this repeat-length variation influenced the translation of CaIMP mRNA, apparently by facilitating translation initiation. Our analyses proposed that the SSR marker derived from 5' UTR of a CaIMP gene is a promising candidate for selection of seed size/weight for agronomic trait improvement of chickpea.Item A draft genome sequence of the pulse crop chickpea (Cicer arietinum L.)(John Wiley & Sons, 2013) Jain, Mukesh; Misra, Gopal; Patel, Ravi K.; Priya, Pushp; Jhanwar, Shalu; Khan, Aamir W.; Shah, Niraj; Singh, Vikas K.; Garg, Rohini; Jeena, Ganga; Yadav, Manju; Kant, Chandra; Sharma, Priyanka; Yadav, Gitanjali; Bhatia, Sabhyata; Tyagi, Akhilesh K.; Chattopadhyay, DebasisCicer arietinum L. (chickpea) is the third most important food legume crop. We have generated the draft sequence of a desi-type chickpea genome using next-generation sequencing platforms, bacterial artificial chromosome end sequences and a genetic map. The 520-Mb assembly covers 70% of the predicted 740-Mb genome length, and more than 80% of the gene space. Genome analysis predicts the presence of 27,571 genes and 210 Mb as repeat elements. The gene expression analysis performed using 274 million RNA-Seq reads identified several tissue-specific and stress-responsive genes. Although segmental duplicated blocks are observed, the chickpea genome does not exhibit any indication of recent whole-genome duplication. Nucleotide diversity analysis provides an assessment of a narrow genetic base within the chickpea cultivars. We have developed a resource for genetic markers by comparing the genome sequences of one wild and three cultivated chickpea genotypes. The draft genome sequence is expected to facilitate genetic enhancement and breeding to develop improved chickpea varieties.Item Analysis of gene expression in response to water deficit of chickpea (Cicer arietinum L.) varieties differing in drought tolerance(BioMed Central, 2010) Jain, Deepti; Chattopadhyay, DebasisChickpea (C. arietinum L.) ranks third in food legume crop production in the world. However, drought poses a serious threat to chickpea production, and development of drought-resistant varieties is a necessity. Unfortunately, cultivated chickpea has a high morphological but narrow genetic diversity, and understanding the genetic processes of this plant is hindered by the fact that the chickpea genome has not yet been sequenced and its EST resources are limited. In this study, two chickpea varieties having contrasting levels of drought-tolerance were analyzed for differences in transcript profiling during drought stress treatment by withdrawal of irrigation at different time points. Transcript profiles of ESTs derived from subtractive cDNA libraries constructed with RNA from whole seedlings of both varieties were analyzed at different stages of stress treatment.Item CIPK6, a CBL-interacting protein kinase is required for development and salt tolerance in plant(Wiley-Blackwell, 2009) Tripathi, Vineeta; Parasuraman, Boominathan; Laxmi, Ashverya; Chattopadhyay, DebasisCalcineurin B-like proteins (CBL) and CBL-interacting protein kinases (CIPK) mediate plant responses to a variety of external stresses. Here we report that Arabidopsis CIPK6 is also required for the growth and development of plants. Phenotype of tobacco plants ectopically expressing a homologous gene (CaCIPK6) from the leguminous plant chickpea (Cicer arietinum) indicated its functional conservation. A lesion in AtCIPK6 significantly reduced shoot-to-root and root basipetal auxin transport, and the plants exhibited developmental defects such as fused cotyledons, swollen hypocotyls and compromised lateral root formation, in conjunction with reduced expression of a number of genes involved in auxin transport and abiotic stress response. The Arabidopsis mutant was more sensitive to salt stress compared to wild-type, while overexpression of a constitutively active mutant of CaCIPK6 promoted salt tolerance in transgenic tobacco. Furthermore, tobacco seedlings expressing the constitutively active mutant of CaCIPK6 showed a developed root system, increased basipetal auxin transport and hypersensitivity to auxin. Our results provide evidence for involvement of a CIPK in auxin transport and consequently in root development, as well as in the salt-stress response, by regulating the expression of genes.Item CAP2 enhances germination of transgenic tobacco seeds at high temperature and promotes heat stress tolerance in yeast(Wiley-Blackwell, 2009) Shukla, Rakesh Kumar; Tripathi, Vineeta; Jain, Deepti; Yadav, Rajiv Kumar; Chattopadhyay, DebasisWe reported earlier that ectopic expression of CAP2, a single AP2 domain containing transcription activator from chickpea (Cicer arietinum) in tobacco improves growth and development, and tolerance to dehydration and salt stress, of the transgenic plants. Here, we report that, in addition, the CAP2-transgenic tobacco seeds also exhibit higher germination efficiency at high temperature and show higher expression levels of genes for tobacco heat shock proteins and a heat shock factor. CAP2 was able to activate the 5¢-upstream activating sequence of tobacco heat shock factor. Surprisingly, expression of CAP2 cDNA in Saccharomyces cerevisiae also enhanced heat tolerance, with increased expression of the gene for yeast heat shock factor 1 (Hsf1) and its target, the gene for yeast heat shock protein 104 (Hsp104). Sequence analysis of the Hsf1 promoter revealed the presence of a dehydration-responsive element ⁄ C-repeat-like element (DRE/ CRE). Recombinant CAP2 protein bound to the DRE/CRE in the Hsf1 promoter in a gel shift assay and transactivated the Hsf1 promoter–His reporter construct. The full-length CAP2 protein was required to provide thermotolerance in yeast. If these findings are taken together, our results suggest that CAP2 is involved in the heat stress response and provides an example of functioning of a plant transcription factor in yeast, highlighting the strong evolutionary conservation of the stress response mechanism.Item Expression of CAP2, an AP2-family transcription factor from chickpea enhances growth and tolerance to dehydration and salt tress in transgenic tobacco(American Society of Plant Biologists, 2006) Shukla, Rakesh K.; Raha, Sumita; Tripathi, Vineeta; Chattopadhyay, DebasisThe APETALA2 (AP2) domain defines a large family of DNA-binding proteins that play important roles in plant morphology, development, and stress response. We describe isolation and characterization of a gene (CAP2) from chickpea (Cicer arietinum) encoding a novel AP2-family transcription factor. Recombinant CAP2 protein bound specifically to C-repeat/dehydration- responsive element in gel-shift assay and transactivated reporter genes in yeast (Saccharomyces cerevisiae) one-hybrid assay. CAP2 appeared to be a single/low copy intronless gene, and the protein product localized in the nucleus. Transcript level of CAP2 increased by dehydration and by treatment with sodium chloride, abscisic acid, and auxin, but not by treatment with low temperature, salicylic acid, and jasmonic acid. The 35S promoter-driven expression of CAP2 in tobacco (Nicotiana tabacum) caused drastic increase in the leaf cell size, and, thereby, in leaf surface area and number of lateral roots. Transgenic plants demonstrated more tolerance to dehydration and salt stress than the wild-type plants. Transgenic plants expressed higher steady-state transcript levels of abiotic stress-response genes NtERD10B and NtERD10C and auxin-response genes IAA4.2 and IAA2.5. Taken together, our results indicated a mutual interrelation between plant growth-development and abiotic stress- response pathways and a probable involvement of CAP2 in both the signaling pathways.
