Xing Jing, Zhao Ruijie, Zhang Qing, Huang Xinru, Yin Tingchao, Zhang Jing, Xu Bin
College of Agro-Grassland Science, Nanjing Agricultural University, Nanjing, China.
Front Plant Sci. 2022 Jun 2;13:922564. doi: 10.3389/fpls.2022.922564. eCollection 2022.
family genes play crucial roles in plant growth, development, and abiotic stress responses. The objective of this study was to identify and characterize the genes in perennial ryegrass ( L.). The results showed that there are 10 in perennial ryegrass that could be classified into three groups with similar genic (exon-intron) structures to their orthologous genes in Arabidopsis and other grass species. Ka/Ks analysis suggested that the and their orthologs were under purifying selection to maintain their conserved function during evolution. Nine out of ten were localized in the cytoplasm and nucleus with the exception of LpSAPK5 which was only observed in the cytoplasm. Most were responsive to various abiotic stress and hormonal (ABA, cytokinin, and ethylene) treatments but were downregulated in leaves and upregulated in roots, suggesting that there were unknown elements in promoters of these genes or unidentified post-transcriptional mechanism responsible for the tissue-dependent stress-regulated expression of these . Furthermore, was identified as a candidate positive regulator in drought tolerance using a yeast ectopic expression system, and showed contrasting expression changes in drought-sensitive and -tolerant ryegrass varieties, suggesting that expression levels of were related to ryegrass drought tolerance. These results will facilitate further functional analysis of for molecular breeding of ryegrass and other related grass species.
家族基因在植物生长、发育及非生物胁迫响应中发挥着关键作用。本研究的目的是鉴定和表征多年生黑麦草（Lolium perenne L.）中的这些基因。结果表明，多年生黑麦草中有10个此类基因，可分为三组，其基因（外显子-内含子）结构与其在拟南芥和其他禾本科物种中的直系同源基因相似。Ka/Ks分析表明，这些基因及其直系同源基因在进化过程中受到纯化选择以维持其保守功能。除仅在细胞质中观察到的LpSAPK5外，十个基因中有九个定位于细胞质和细胞核。大多数基因对各种非生物胁迫和激素（脱落酸、细胞分裂素和乙烯）处理有响应，但在叶片中下调而在根中上调，这表明这些基因的启动子中存在未知的顺式作用元件或负责这些基因组织依赖性胁迫调节表达的未鉴定的转录后机制。此外，利用酵母异位表达系统鉴定出一个基因作为耐旱性的候选正调控因子，并且该基因在干旱敏感和耐旱黑麦草品种中表现出相反的表达变化，这表明该基因的表达水平与黑麦草的耐旱性有关。这些结果将有助于进一步对这些基因进行功能分析，以用于黑麦草和其他相关禾本科物种的分子育种。
