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为研究陆地棉甲硫氨酸裂解酶(Methionineγ-lyase)基因的结构与功能,本研究以陆地棉中9807叶片为试验材料克隆得到棉花甲硫氨酸裂解酶(Methionineγ-lyase)基因c DNA全长,命名为GhMGL11 (Cottongen:Gh_A12G2168).蛋白序列分析该基因的编码区序列全长1 359 bp,编码452氨基酸;GhMGL11蛋白属于亲水性蛋白,预测含有41个磷酸化位点;亚细胞定位显示位于细胞质,无信号肽.序列比对分析,该基因含有Cys_Met_Meta_PP家族特有的保守结构域Cys_Met_Meta_PP,属于PLP (Pyridoxal phosphate)依赖性氨基转移酶中的一种.系统进化分析,陆地棉GhMGL11蛋白与可可(Theobroma cacao)亲缘关系较近.在陆地棉中发现23个与GhMGL11基因同源的含有Cys_Met_Meta_PP结构域的基因.组织特异性分析,GhMGL11基因在棉花根、茎、叶中均有表达,其中在根中的表达量最高;碱胁迫处理后不同时间内,该基因的表达量先升高后降低,说明该基因表达受碱胁迫影响.“,”In this study, full-length c DNA of methionine γ-lyase gene was cloned from 9807 leaf in upland cotton, which was named GhMGL11 (Cottongen: Gh_A12 G2168) in order to study the structure and function of methionine γ-lyase gene. Sequence analysis of protein showed that the gene had the full length of 1 359 bp in coding region, encoding 452 amino acids. GhMGL11 protein was hydrophilic and predicted to contain 41 phosphorylation sites, of which the subcellular located in the cytoplasm with no signal peptide. Sequence alignment analysis showed that this gene contained the Cys_Met_Meta_PP domain, a specific conserved domain of Cys_Met_Meta_PP family, which was one of pyridoxal-dependent aminotransferases (PLPs). Phylogenetic analysis showed that there was closer evolutionary relationship between GhMGL11 protein in Gossypium hirsutum and Theobroma cacao. Twenty-three genes containing Cys_Met_Meta_PP domain were found in Gossypium hirsutum, which were homologous with GhMGL11 gene. Tissue-specific analysis showed that GhMGL11 gene was expressed in roots, stems and leaves of cotton, and had highest expression level in roots. In different time under alkaline stress, the expression of GhMGL11 gene increased at first and then decreased, indicating that the gene was affected by alkaline stress.