Regier J C, Kafatos F C
J Biol Chem. 1981 Jun 25;256(12):6444-51.
The protein products from one of the two major silkmoth chorion multigene families contain blocked NH2 termini. The blocked residue has been identified as pyrrolidonecarboxylic acid. Its formation occurs post-translationally, by modification of NH2-terminal glutamine, after removal of a 20-residue-long "signal peptide." Pyrrolidonecarboxylic acid formation begins within minutes after polypeptide chain termination and is largely, although not entirely, complete by 60 min. Pyrrolidonecarboxylic acid thus appears to be formed both within the cell and in the extracellular chorion. Another class of minor chorion proteins also appears to contain pyrrolidonecarboxylic acid.
两个主要的蚕蛾绒毛膜多基因家族之一的蛋白质产物含有被封闭的NH2末端。已确定被封闭的残基为吡咯烷酮羧酸。它的形成发生在翻译后，是通过在去除一个20个残基长的“信号肽”后对NH2末端谷氨酰胺进行修饰而产生的。吡咯烷酮羧酸的形成在多肽链终止后几分钟内开始，并且在60分钟时基本（尽管不是完全）完成。因此，吡咯烷酮羧酸似乎在细胞内和细胞外的绒毛膜中均有形成。另一类次要的绒毛膜蛋白似乎也含有吡咯烷酮羧酸。
