珍珠小米是一种营养谷物,主要生长在恶劣的环境中,使其成为在分子水平上研究耐热性机制的理想作物。尽管比其他作物对高温有更好的耐性,热应力对作物产生负面影响,对生产力增长构成威胁。因此,为了了解热响应基因,两个对比珍珠小米自交系的叶子和根样本,EGTB1034(耐热)和EGTB1091(热敏),经受热处理条件并产生全基因组转录组。我们发现了13,464个差异表达基因(DEG),其中6932在叶和根组织中下调,6532在叶和根组织中上调。对两种基因型的基于组织的转录组数据的成对分析证明了基因的独特基因型和组织特异性表达。与叶子相比,根表现出更多的DEG,强调珍珠小米的不同适应策略。大量编码ROS清除酶的基因,WRKY,NAC,参与营养吸收的酶,蛋白激酶,光合酶,在胁迫条件下,参与温度应激反应机制交叉对话的热休克蛋白(HSPs)和几种转录因子(TFs)被激活。核糖体蛋白作为关键的枢纽基因出现,与表达并参与热应激反应的关键基因高度互动。热胁迫下珍珠谷子次生代谢产物的合成和代谢途径显著富集。谷子基因组中HSPs和TFs的比较同种关系分析显示,与谷子相比,谷子与谷子的共线性更大,大米,高粱,和玉米。在这项研究中,1906年,识别了未注释的DEG,提供对热应激分子反应的新参与者的见解。已确定的基因有望加快珍珠小米和类似作物的耐热性品种发育,在高温环境中培养韧性和提高谷物产量。
Pearl millet is a nutri-cereal that is mostly grown in harsh environments, making it an ideal crop to study heat tolerance mechanisms at the molecular level. Despite having a better-inbuilt tolerance to high temperatures than other crops, heat stress negatively affects the crop, posing a threat to productivity gain. Hence, to understand the heat-responsive genes, the leaf and root samples of two contrasting pearl millet inbreds, EGTB 1034 (heat tolerant) and EGTB 1091 (heat sensitive), were subjected to heat-treated conditions and generated genome-wide
transcriptomes. We discovered 13,464 differentially expressed genes (DEGs), of which 6932 were down-regulated and 6532 up-regulated in leaf and root tissues. The pairwise analysis of the tissue-based transcriptome data of the two genotypes demonstrated distinctive genotype and tissue-specific expression of genes. The root exhibited a higher number of DEGs compared to the leaf, emphasizing different adaptive strategies of pearl millet. A large number of genes encoding ROS scavenging enzymes, WRKY, NAC, enzymes involved in nutrient uptake, protein kinases, photosynthetic enzymes, and heat shock proteins (HSPs) and several transcription factors (TFs) involved in cross-talking of temperature stress responsive mechanisms were activated in the stress conditions. Ribosomal proteins emerged as pivotal hub genes, highly interactive with key genes expressed and involved in heat stress response. The synthesis of secondary metabolites and metabolic pathways of pearl millet were significantly enriched under heat stress. Comparative synteny analysis of HSPs and TFs in the foxtail millet genome demonstrated greater collinearity with pearl millet compared to proso millet, rice, sorghum, and maize. In this study, 1906 unannotated DEGs were identified, providing insight into novel participants in the molecular response to heat stress. The identified genes hold promise for expediting varietal development for heat tolerance in pearl millet and similar crops, fostering resilience and enhancing grain yield in heat-prone environments.