玉米CaM基因家族鉴定及特性分析

利用玉米基因组等多种数据库搜索CaM家族基因，对玉米CaM基因家族进行筛选与鉴定，对家族成员的基因结构、等电点、分子量、亚细胞定位、蛋白保守域等蛋白基本特性进行分析。同时分析不同组织和干旱胁迫条件下该类基因的表达情况，进一步利用qRT-PCR技术检测5个具有代表性的CaM基因在干旱处理条件下的表达变化。结果显示，共获得14个CaM基因，根据3’-UTR序列构建的系统进化树显示可分为4个亚家族。根据蛋白质的氨基酸序列，可分为3种亚型。家族成员蛋白分子量大多数为16.8 kD左右，等电点介于4.10～4.30，该家族蛋白保守结构域由3～4个EF手型结构域组成，主要定位于细胞质和细胞核。Zmcal4、Zmcal5和Zmcal6基因在各组织中表达非常低，干旱会抑制家族大部分成员的表达，覆水处理后，Zmcal3-1、Zmcal3-2、Zmcal3-3、Zmcal3-4的表达可恢复到对照水平，推测这几个基因可能参与干旱胁迫反应。qRT-PCR结果表明，干旱会抑制CaM基因的表达，随着干旱处理时间的增加，CaM基因的表达量逐渐降低，与生信分析结果一致。

Genome-Wide Identification and Characterization Analysis of CaM Gene Family in Maize

Maize genome and other databases were used to search for calmodulin family genes. The CaM gene family was identified, and then the basic protein characteristics of the family members, such as gene structure, isoelectric point, molecular weight, subcellular localization and protein conserved domain were analyzed. The expression levels of these genes in different tissues and under drought stress were also analyzed. In addition, qRT-PCR was used to detect the expression levels of five representative CaM genes under drought treatments. The results showed that a total of 14 CaM genes were identified, which could be divided into four subfamilies based on the 3''- UTR sequence and three isoforms based on the amino acid sequence of proteins. The gene structures of them are very conserved; the molecular weight of most family members was about 16.8kD, and the isoelectric point is between 4.10 and 4.30. The conserved domain of this family composed of 3 to 4 EF hand domains. Most of them localized in cytoplasm and nucleus. The expression of Zmcal4, Zmcal5 and Zmcal6 genes were very low in all tissues, and the expression of most members of CaM gene family was inhibited by drought. The expression of Zmcal3-1, Zmcal3-2, Zmcal3-3 and Zmcal3-4 could be restored to the control level after rewatered, which suggested that these genes might be involved in drought stress response. The result of qRT-PCR showed that drought inhibited the expression of CaM gene, and the expression level of CaM gene decreased gradually with drought treatment.