植物Gly-RLK基因家族鉴定及其在苹果中的表达分析

类受体激酶（receptor like kinase，RLK）在植物生长发育和环境适应中起重要作用。前期研究发现苹果（Malus ? domestica）中存在一类具有Glyco_18胞外结构域（SM000636或SM000704）的RLK，命名为Glyco_18-RLK（Gly-RLK）。本试验中以Glyco_18和Pkinase（SM000220）保守域全蛋白序列为种子序列，对53种被子植物基因组中的Gly-RLK进行鉴定，并分析其进化特征；明确苹果Gly-RLK（MdGly-RLK）的理化性状、亚细胞定位，基因在染色体上的分布、启动子区域的顺式作用元件和表达模式。结果表明，仅19种植物中存在Gly-RLK，家族成员数介于1 ~ 20，单子叶植物中均未发现该家族成员。根据进化分析将其分为8个亚组，亚组Ⅲ、Ⅶ和Ⅷ分布基因数较多。共发现6个MdGly-RLK，其编码的氨基酸序列大小、分子量和等电点分别介于451 ~ 776、50.99 ~ 87.33 kD和5.95 ~ 8.21，主要位于质膜，4个为串联重复。MdGly-RLK在苹果各组织和品种间存在不同的表达模式；接种苹果腐烂病菌（Valsa mali）后，6个MdGly-RLK均差异表达，MdGly-RLK6（MD15G1156900）可上调至对照的16.33倍。综上，Gly-RLK仅在部分双子叶植物中存在，家族成员的扩增速度较快。MdGly-RLK响应苹果生长发育和黑腐皮壳菌信号，MdGly-RLK6可作为苹果抗腐烂病研究的候选基因。

Identification of Plant Gly-RLK Gene Family and Expressional Analysis in Apple

Receptor like kinase（RLK）take the crucial role in plant growth，development and environmental adaptation. In previous studies，one kind of apple（Malus × domestica）had glyco_18 RLK with extracellular domain（SM000636 or SM000704）named Glyco_18-RLK（MdGly-RLK）. In this test， Glyco_18 and Pkinase（SM000220）conserved domain whole protein sequences were seed sequences. Gly-RLK in 53 angiosperms was identified and its evolutionary characteristics were analyzed. Based on bioinformatics expression analysis，the physical and chemical properties，subcellular location，gene distribution on chromosome，cis-elements and expression patterns of promoter region of apple Gly-RLK were determined. The results showed that only 19 species of plants had Gly-RLK，and the number of family members ranged from 1 to 20. No family members were found in all monocotyledonous plants. According to the evolutionary analysis，it was divided into 8 subgroups，with more genes distributed in subgroup Ⅲ，Ⅶ and Ⅷ. We identified 6 Gly-RLKs from apple genome. Their amino acid sequence size，molecular weight and isoelectric point were 451–776，50.99–87.33 kD，and 5.95–8.21，respectively. They were mainly located in plasma membrane，and four of them were tandem repeat. There were different expression patterns of MdGly-RLK in different apple tissues and varieties. After inoculation with Valsa mali，the expression of six MdGly-RLKs in apples was different，and MdGly-RLK6（MD15G1156900）could be increased to 16.33 times of the control. To sum up，Gly-RLK only exist in some dicotyledons，and the expansion speed of family members is faster. MdGly-RLK can respond to the signals of apple growth and development and black rot fungus. MdGly-RLK6 can be used as a candidate gene for the study of apple anti rot.