Sredy J, Spector A
Exp Eye Res. 1984 Nov;39(5):653-64. doi: 10.1016/0014-4835(84)90064-2.
The phosphorylation of bovine and human lens polypeptides was examined using an in vitro labeling assay with [gamma-32P]-ATP, followed by SDS-PAGE and radioautography. The major protein phosphorylation in all lens preparations was cAMP-dependent. The effect of cAMP could be depressed by monovalent ions. Phosphorylated polypeptides were detected in capsule-epithelial and outer cortical but not inner cortical-nuclear preparations. Differences in phosphorylated polypeptide distributions and molecular weight patterns were observed between bovine capsule-epithelium and outer cortex fiber cells and bovine and human preparations. Human cataractous lens preparations had the same pattern of phosphorylation as human normal lens preparations but with much less 32P incorporation. Major phosphorylated polypeptides in the 100 000 dalton, 60 000 dalton and 43 000 dalton range were detected in both bovine and human preparations. A 32 000 dalton phosphorylated polypeptide appeared exclusively in the bovine capsule-epithelium and a phosphorylated 23 000 dalton polypeptide was detected only in outer cortical preparations.
利用[γ-32P]-ATP体外标记试验，随后进行SDS-聚丙烯酰胺凝胶电泳（SDS-PAGE）和放射自显影，检测牛和人晶状体多肽的磷酸化情况。所有晶状体标本中的主要蛋白质磷酸化均依赖于环磷酸腺苷（cAMP）。一价离子可抑制cAMP的作用。在晶状体囊膜上皮和外皮质中检测到磷酸化多肽，但在内皮质-核标本中未检测到。观察到牛晶状体囊膜上皮和外皮质纤维细胞以及牛和人标本之间磷酸化多肽分布和分子量模式存在差异。人白内障晶状体标本的磷酸化模式与正常人晶状体标本相同，但32P掺入量少得多。在牛和人标本中均检测到分子量在100000道尔顿、60000道尔顿和43000道尔顿范围内的主要磷酸化多肽。一种32000道尔顿的磷酸化多肽仅出现在牛晶状体囊膜上皮中，而一种23000道尔顿的磷酸化多肽仅在外皮质标本中检测到。
