Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, Hunan, 410128, China; Oil Crops Research, Hunan Agricultural University, Changsha, Hunan, 410128, China; Hunan Branch of National Oilseed Crops Improvement Center, Changsha, Hunan, 410128, China.
Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China, Hunan Agricultural University, Changsha, Hunan, 410128, China.
J Plant Physiol. 2020 Dec;255:153251. doi: 10.1016/j.jplph.2020.153251. Epub 2020 Aug 14.
Calmodulin (CaM) and calmodulin-like (CML) proteins are primary calcium (Ca) sensors and are involved in the regulation of plant development and stress responses by converting calcium signals into transcriptional responses, protein phosphorylation, or metabolic changes. However, the characterization and expression profiling of CaM/CML genes in Brassica napus remain limited. The present study reports that 25 BnaCaM and 168 BnaCML genes were identified in B. napus. The phylogenetics, gene structures, gene motifs, gene chromosomal locations, syntenic and Ka/Ks analysis, promoter cis-acting elements, and expression characteristics in various organs and under abiotic stress were evaluated. The phylogenetic results revealed a total of 11 subgroups, including one unique clade of CaMs distinct from CMLs. Most of group I (CaM), II, III, and X members are intron rich, while members from the other seven groups are intron-less. The majority of CaM/CML proteins have four EF-hands. Syntenic analysis showed that 91.3 % orthologous CaM/CML gene pairs between B. rapa and B. oleracea were retained as homologous gene pairs in B. napus. Ka/Ks analysis indicated that the majority of BnaCaM/CML experienced purifying selection. Expression analysis showed that BnaCaMs genes are highly and ubiquitously expressed in all of the organs and tissues examined, while distinct BnaCMLs are expressed specifically in particular organs and tissues. In total, 129 BnaCaM/CML were induced by abiotic stress and phytohormones. BnaCMLs from group IV, VI, VIII, and X were strongly induced by freezing treatment, but were not or just slightly induced by chilling treatment. The present study is the first to analyze the CaM/CML gene family in B. napus, which is useful for understanding the functions of the BnaCaM/CML in modulating plant responses to abiotic stress, especially freezing stress.
钙调素（CaM）和钙调素样蛋白（CML）是主要的钙离子（Ca）传感器，通过将钙信号转化为转录反应、蛋白质磷酸化或代谢变化，参与植物发育和应激反应的调节。然而，油菜中 CaM/CML 基因的特征和表达谱仍有限。本研究报告在油菜中鉴定出 25 个 BnaCaM 和 168 个 BnaCML 基因。评估了系统发育、基因结构、基因基序、基因染色体位置、共线性和 Ka/Ks 分析、启动子顺式作用元件以及在各种器官和非生物胁迫下的表达特征。系统发育结果表明，共分为 11 个亚组，包括一个与 CML 不同的 CaM 特有分支。大多数 I 组（CaM）、II、III 和 X 成员富含内含子，而其他七个组的成员则没有内含子。大多数 CaM/CML 蛋白有四个 EF 手。共线性分析表明，B. rapa 和 B. oleracea 之间的 91.3%同源 CaM/CML 基因对在油菜中保留为同源基因对。Ka/Ks 分析表明，大多数 BnaCaM/CML 经历了纯化选择。表达分析表明，BnaCaMs 基因在所有检测到的器官和组织中高度广泛表达，而不同的 BnaCMLs 则特异性表达于特定的器官和组织。总共 129 个 BnaCaM/CML 被非生物胁迫和植物激素诱导。来自第四、第六、第八和第十组的 BnaCMLs 强烈地被冻融处理诱导，但不受冷处理或仅轻微诱导。本研究首次分析了油菜中的 CaM/CML 基因家族，这有助于理解 BnaCaM/CML 调节植物对非生物胁迫，特别是冻融胁迫反应的功能。
