Organization and evolution of the human epidermal keratinocyte transglutaminase I gene.
Organization and evolution of the human epidermal keratinocyte transglutaminase I gene.
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人表皮角质形成细胞转谷氨酰胺酶 I 基因的组织和进化。
DOI：
10.1073/pnas.89.10.4476
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发表时间：
1992
影响因子：
11.1
通讯作者：
Goldsmith,LA
中科院分区：
文献类型：
--
作者：
Polakowska,RR;Eickbush,T;Falciano,V;Razvi,F;Goldsmith,LA
转谷氨酰胺酶(TGase；蛋白质-谷氨酰胺：胺-γ-谷氨基转移酶，EC 2.3.2.13)是一种钙依赖的交联酶，可在翻译后修饰蛋白质。已经确定了几种不同类型的TGase，它们似乎是由一个密切相关的基因家族编码的。我们分离了编码人类角质形成细胞特异性I型TGase(TGase I)的基因，并对其染色体结构进行了鉴定。TGase I基因由15个外显子组成，由14个内含子隔开，具有限制性片段长度多态性。外显子似乎编码功能和/或结构结构域：外显子I和外显子XV的一部分编码非翻译区，而外显子VII和XI分别包含活性部位和推测的钙结合结构域。有趣的是，TGase I的外显子VI包含一个共识的Arg-Gly-Asp三肽序列，该序列的存在表明该酶具有耐人寻味的细胞外功能。根据氨基酸序列的相似性，我们提出了TGase家族七个已知成员的可能的系统发育树。这些论点表明，活性酶首先进化，结构人红细胞膜蛋白4.2(带4.2)的氨基酸序列发生了迅速的变化。结果表明，条带4.2由II型TGase进化而来，而凝血因子XIII亚单位a则由I型进化而来。
Transglutaminases (TGases; protein-glutamine:amine gamma-glutamyltransferase, EC 2.3.2.13) are calcium-dependent crosslinking enzymes that modify proteins posttranslationally. Several distinct types of TGases have been identified, which appear to be encoded by a family of closely related genes. We isolated the gene encoding human keratinocyte-specific type I TGase (TGase I) and characterized its chromosomal organization. The TGase I gene consists of 15 exons separated by 14 introns and exhibits a restriction fragment length polymorphism. Exons appear to encode functional and/or structural domains: exon I and part of exon XV encode untranslated regions, whereas exons VII and XI contain the active site and a presumptive calcium-binding domain, respectively. Interestingly, exon VI of TGase I contains a consensus Arg-Gly-Asp tripeptide sequence whose presence suggests an intriguing extracellular function for the enzyme. We present a likely phylogenetic tree for seven known members of the TGase family based on amino acid sequence similarity. Arguments presented suggest that the active enzyme evolved first and the structural human erythrocyte membrane protein 4.2 (band 4.2) has undergone a rapid change in amino acid sequence. It follows that band 4.2 evolved from the type II TGases, whereas factor XIII subunit a evolved from the type I group.