Resing K A, Walsh K A, Dale B A
J Cell Biol. 1984 Oct;99(4 Pt 1):1372-8. doi: 10.1083/jcb.99.4.1372.
A major event in the keratinization of epidermis is the production of the histidine-rich protein filaggrin (26,000 mol wt) from its high molecular weight (greater than 350,000) phosphorylated precursor (profilaggrin). We have identified two nonphosphorylated intermediates (60,000 and 90,000 mol wt) in NaSCN extracts of epidermis from C57/Bl6 mice by in vivo pulse-chase studies. Results of peptide mapping using a two-dimensional technique suggest that these intermediates consist of either two or three copies of filaggrin domains. Each of the intermediates has been purified. The ratios of amino acids in the purified components are unusual and essentially identical. The data are discussed in terms of a precursor containing tandem repeats of similar domains. In vivo pulse-chase experiments demonstrate that the processing of the high molecular weight phosphorylated precursor involves dephosphorylation and proteolytic steps through three-domain and two-domain intermediates to filaggrin. These processing steps appear to occur as the cell goes through the transition cell stage to form a cornified cell.
表皮角质化过程中的一个主要事件是，富含组氨酸的蛋白质丝聚合蛋白（分子量26,000）由其高分子量（大于350,000）的磷酸化前体（前丝聚合蛋白）产生。通过体内脉冲追踪研究，我们在C57/Bl6小鼠表皮的硫氰酸钠提取物中鉴定出两种非磷酸化中间体（分子量60,000和90,000）。使用二维技术进行肽图谱分析的结果表明，这些中间体由两个或三个丝聚合蛋白结构域拷贝组成。每种中间体均已纯化。纯化成分中的氨基酸比例不同寻常且基本相同。根据包含相似结构域串联重复序列的前体对数据进行了讨论。体内脉冲追踪实验表明，高分子量磷酸化前体的加工过程涉及去磷酸化和蛋白水解步骤，通过三结构域和两结构域中间体生成丝聚合蛋白。这些加工步骤似乎是在细胞经历过渡细胞阶段形成角质化细胞时发生的。
