Ambili M, Sudhakaran P R
Department of Biochemistry, University of Kerala, Kariavattom, Trivandrum, India.
Biochem Mol Biol Int. 1998 Jun;45(2):389-99. doi: 10.1080/15216549800202772.
The matrix metalloproteinases appear to play a key role in mammary tissue remodeling during involution. By immunoprecipitation and immunoblot using antibodies against 60K gelatinase which appears during involution a 90K polypeptide has been identified as its inactive proenzyme in the early involuting rat mammary gland. 90K polypeptide was isolated from the second day involuting rat mammary gland by immunoaffinity chromatography. On proteolytic digestion, the inactive 90K polypeptide was converted to active gelatinase. Primary cultures of mammary epithelial cells secreted the 90K polypeptide. These results indicated that the 60K inducible MMP involved in mammary gland involution and remodeling is produced as a 90K proenzyme which is activated by proteolysis in the extracellular sites.
基质金属蛋白酶似乎在乳腺组织退化过程中的重塑中起关键作用。通过使用针对退化过程中出现的60K明胶酶的抗体进行免疫沉淀和免疫印迹，在早期退化的大鼠乳腺中已鉴定出一种90K多肽作为其无活性的酶原。通过免疫亲和色谱法从退化第二天的大鼠乳腺中分离出90K多肽。经蛋白水解消化后，无活性的90K多肽转化为活性明胶酶。乳腺上皮细胞的原代培养物分泌90K多肽。这些结果表明，参与乳腺退化和重塑的60K诱导型基质金属蛋白酶是以90K酶原的形式产生的，该酶原在细胞外位点通过蛋白水解作用被激活。
