Dipartimento di Scienze Agrarie Alimentari e Forestali, Università degli Studi di Palermo, viale delle scienze ed. 4, Palermo, 90128, Italy.
Dipartimento di Biologia, Università degli Studi di Firenze, Via Madonna del Piano 6, Sesto Fiorentino, FI, 50019, Italy.
BMC Plant Biol. 2019 May 10;19(1):194. doi: 10.1186/s12870-019-1794-y.
Our study is the first to provide RNA-Seq data analysis related to transcriptomic responses towards drought across different crops. The aim was to identify and map which genes play a key role in drought response on leaves across different crops. Forty-two RNA-seq samples were analyzed from 9 published studies in 7 plant species (Arabidopsis thaliana, Solanum lycopersicum, Zea mays, Vitis vinifera, Malus X domestica, Solanum tuberosum, Triticum aestivum).
Twenty-seven (16 up-regulated and 11 down-regulated) drought-regulated genes were commonly present in at least 7 of 9 studies, while 351 (147 up-regulated and 204 down-regulated) were commonly drought-regulated in 6 of 9 studies. Across all kind of leaves, the drought repressed gene-ontologies were related to the cell wall and membrane re-structuring such as wax biosynthesis, cell wall organization, fatty acid biosynthesis. On the other hand, drought-up-regulated biological processes were related to responses to osmotic stress, abscisic acid, water deprivation, abscisic-activated signalling pathway, salt stress, hydrogen peroxide treatment. A common metabolic feature linked to drought response in leaves is the repression of terpenoid pathways. There was an induction of AL1 (alfin-like), UGKYAH (trihelix), WRKY20, homeobox genes and members of the SET domain family in 6 of 9 studies. Several genes involved in detoxifying and antioxidant reactions, signalling pathways and cell protection were commonly modulated by drought across the 7 species. The chromosome (Chr) mapping of these key abiotic stress genes highlighted that Chr 4 in Arabidopsis thaliana, Chr 1 in Zea mays, Chr 2 and Chr 5 in Triticum aestivum contained a higher presence of drought-related genes compared to the other remaining chromosomes. In seedling studies, it is worth notice the up-regulation of ERF4 and ESE3 (ethylene), HVA22 (abscisic acid), TIR1 (auxin) and some transcription factors (MYB3, MYB94, MYB1, WRKY53 and WRKY20). In mature leaves, ERF1 and Alfin-like 1 were induced by drought while other transcription factors (YABBY5, ARR2, TRFL2) and genes involved phospholipid biosynthesis were repressed.
The identified and mapped genes might be potential targets of molecular breeding activities to develop cultivars with enhanced drought resistance and tolerance across different crops.
我们的研究首次提供了与不同作物叶片干旱响应相关的转录组反应的 RNA-Seq 数据分析。目的是鉴定和绘制哪些基因在不同作物叶片的干旱响应中起关键作用。对来自 9 个已发表研究的 42 个 RNA-seq 样本进行了分析，这些研究涉及 7 个植物物种（拟南芥、番茄、玉米、葡萄、苹果、马铃薯、小麦）。
在至少 7 项研究中，有 27 个（16 个上调和 11 个下调）干旱调节基因共同存在，而在 6 项研究中，有 351 个（147 个上调和 204 个下调）干旱调节基因共同存在。在所有类型的叶片中，受干旱抑制的基因本体论与细胞壁和膜重构有关，如蜡质生物合成、细胞壁组织、脂肪酸生物合成。另一方面，干旱上调的生物学过程与对渗透胁迫、脱落酸、水分胁迫、脱落酸激活信号通路、盐胁迫、过氧化氢处理的反应有关。与叶片干旱反应相关的一个常见代谢特征是萜类途径的抑制。在 6 项研究中，AL1（alfin-like）、UGKYAH（三螺旋）、WRKY20、同源盒基因和 SET 结构域家族成员被诱导。在 7 个物种中，参与解毒和抗氧化反应、信号通路和细胞保护的几个基因通常受到干旱的调节。这些关键非生物胁迫基因的染色体（Chr）定位表明，拟南芥的 Chr4、玉米的 Chr1、小麦的 Chr2 和 Chr5 中与干旱相关的基因比其他剩余染色体的存在更高。在幼苗研究中，值得注意的是 ERF4 和 ESE3（乙烯）、HVA22（脱落酸）、TIR1（生长素）和一些转录因子（MYB3、MYB94、MYB1、WRKY53 和 WRKY20）的上调。在成熟叶片中，干旱诱导 ERF1 和 Alfin-like 1，而其他转录因子（YABBY5、ARR2、TRFL2）和参与磷脂生物合成的基因受到抑制。
鉴定和定位的基因可能是分子育种活动的潜在目标，以开发不同作物抗旱性和耐受力增强的品种。
