Transglutaminase reactivity of human involucrin.
Transglutaminase reactivity of human involucrin.
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人外皮蛋白的转谷氨酰胺酶反应性。
DOI：
10.1159/000029905
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Eckert,RL
中科院分区：
文献类型：
--
作者：
Lambert,A;Ekambaram,M;Robinson,N;Eckert,RL
人外皮蛋白 (hINV) 通过形成转谷氨酰胺酶 (TG) 依赖性蛋白间 ε-(γ-谷氨酰) 赖氨酸键组装成角化结构。 hINV 序列包含 150 个谷氨酰胺残基，可作为潜在的交联形成位点。目前的研究旨在评估 hINV 在最佳条件下且在没有其他底物的情况下可以作为 TG 底物发挥作用的程度。 hINV 与 TG 一起孵育会导致每个 hINV 分子形成 4-5 个异肽键。当反应中包含小胺供体14 C-腐胺时，48个Q残基被标记。同位素分布和序列分析表明14 C-腐胺标记位点位于整个蛋白质中。我们目前的结果表明，许多 hINV Q 残基可用于交联形成，并且 hINV 可以以非常高的交联密度进行交联。这些结果表明，在体内，hINV 结构以外的因素限制了用于交联形成的残基数量。
Human involucrin (hINV) is assembled into cornified structures via formation of transglutaminase (TG)-dependent interprotein ε-(γ-glutamyl)lysine bonds. The hINV sequence includes 150 glutamine residues that could function as potential sites of cross-link formation. The present studies were designed to evaluate the extent to which hINV can function as a TG substrate under optimal conditions and in the absence of other substrates. Incubation of hINV with TG results in formation of 4–5 isopeptide bonds per hINV molecule. When the small amine donor14C-putrescine is included in the reaction, 48 Q residues are labled. Isotope distribution and sequence analysis suggests that the14C-putrescine-labeled sites are located throughout the protein. Our present results show that many hINV Q residues can be utilized for cross-link formation, and that hINV can be cross-linked at very high cross-link densities. These results suggest that, in vivo, factors other than hINV structure limit the number of residues used for cross-link formation.