The aim of this work was to study the regulation of coffee DREB-like genes in leaves of C. arabica subjected to cold, heat, low relative humidity, exogenous abscisic acid and high light stress, as well as in leaves and roots of drought-tolerant and drought-susceptible clones of Coffea canephora subjected to water limitation. In C. arabica, CaERF017 was the most expressed gene under low temperatures and relative humidity, while low humidity and high temperatures up-regulated the expression of CaERF053 and CaERF014, respectively. Under water limitation, CcDREB1B, CcRAP2.4, CcERF027, CcDREB1D and CcTINY were the most expressed genes mainly in leaves of drought-tolerant C. canephora. On the other hand, expression of the CcERF016, CcRAP2.4 and CcDREB2F genes was highly up-regulated under water limitation in the roots of drought-susceptible C. canephora clone 22. We previously reported fine-tuned regulation of CcDREB1D promoter haplotypes (HP15, HP16 and HP17) in transgenic C. arabica subjected to low humidity. Here, we investigated the regulation of these haplotypes under high light, cold, heat, and abscisic acid (ABA) stress. In apical buds and leaf guard cells, GUS-stained percentages were higher in pHP16L-transformed plants subjected to low humidity, high light and ABA stress than in pHP17L- and pHP15L-transformed plants. We also reported up-regulated expression of the endogenous CaDREB1D gene for both the cold and low humidity in leaves of pHP16L-transformed C. arabica suggesting a key role of this gene in controlling the responses of coffee plants to abiotic stress probably through an ABA-dependent pathway.

中文翻译：

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DREB样基因在各种非生物胁迫下在小食咖啡和阿拉伯咖啡中的表达

这项工作的目的是研究在干旱，高温，低相对湿度，外源脱落酸和高光胁迫下以及干旱和干旱的叶片和根中，阿拉伯咖啡叶片中DREB样基因的调控。水分受限的耐咖啡和耐旱咖啡克隆。在阿拉伯咖啡中，CaERF017是在低温和相对湿度下表达最多的基因，而在低湿度和高温下分别上调CaERF053和CaERF014的表达。在水限制下，CcDREB1B，CcRAP2.4，CcERF027，CcDREB1D和CcTINY是表达最强的基因，主要在耐旱的C. canephora叶片中。另一方面，CcERF016，CcRAP2.4和CcDREB2F基因的表达在干旱限制下对干旱易感的C. canephora克隆22的根中高度上调。我们先前曾报道过转基因阿拉伯咖啡中CcDREB1D启动子单倍型（HP15，HP16和HP17）的微调调控。湿度低。在这里，我们研究了在强光，冷，热和脱落酸（ABA）胁迫下这些单倍型的调控。在顶芽和叶片保卫细胞中，在低湿度，高光和ABA胁迫下，经pHP16L转化的植物的GUS染色百分比高于经pHP17L和pHP15L转化的植物。我们还报告了内源性CaDREB1D基因在pHP16L转化的阿拉伯咖啡叶片中的寒冷和低湿状态下的表达上调，表明该基因在控制咖啡植物对非生物胁迫响应中的关键作用可能是通过ABA-依赖途径。