Investigation of Transcriptome Response in Sorghum Bicolor Under Drought Stress By Bioinformatics Approach

Background and aim: drought stress is one of the main environmental stress that affects growth and productivity of crop plants. understanding the molecular mechanisms of drought tolerance would greatly promote its cultivation and can give us a better view of how to improve the global food production. in this regard, transcriptomic studies, especially rna sequencing, have made a large amount of transcriptome data accessible. in recent years, advanced statistical analysis, such as meta-analysis, through the integration of the information from different sources, provides a new opportunity to identify different expression genes (degs).the aim of this study is to investigate different expressions genes under drought stress conditions in sorghum bicolor to identify genes that their products are key molecules in response to drought stress.methods: we conducted a meta-analysis of drought stress response in 8 sorghum cultivars by analyzing a total of 16 rnaseq samples including 8 control and 8 drought stress sample. meta-analysis was performed by using the r package metaseq. fisher's method was used to combine p-values. after identifying degs from meta-analysis, gene ontology (go) enrichment analysis was used to predict the functions of the degs.results: our results identified a total 6907 degs which 1895 and 4812 were up and down-regulated under drought stress in the sorghum leaves, respectively (genes with a p-value <0.01 were considered as degs). the most of degs associated to the metabolic process (go:0008152), cellular process (go:0009987), catalytic activity (go:0003824), binding (go:0005488), cell (go:0005623) and organelle (go:0043226) categories. therefore, go enrichment results revealed that the go categories related to drought tolerance. adf5, dehydrin dhn1, serine/threonine phosphatases, lea proteins family, nadp-dependent malic enzyme and heat shock protein binding were some of the important genes that up-regulated in response to drought stress. also we identified several transcription factor genes including wrky transcription factor, heat stress transcription factor, bzip transcription factor, ethylene-responsive transcription factor and homeobox-leucine zipper protein, that play an important role in response to drought.conclusion: this study contributes to a better understanding of the molecular mechanisms of sorghum responses to drought stress and could be useful for developing resistant sorghum cultivars.