An alternative processing of integrin alpha(v) subunit in tumor cells by membrane type-1 matrix metalloproteinase - PubMed (original) (raw)

. 2002 Mar 1;277(9):7377-85.

doi: 10.1074/jbc.M109580200. Epub 2001 Dec 10.

Affiliations

Free article

An alternative processing of integrin alpha(v) subunit in tumor cells by membrane type-1 matrix metalloproteinase

Boris I Ratnikov et al. J Biol Chem. 2002.

Free article

Abstract

Membrane type-1 matrix metalloproteinase (MT1-MMP) and alpha(v)beta(3) integrin are both essential to cell invasion. Maturation of integrin pro-alpha(v)chain (pro-alpha(v)) involves its cleavage by proprotein convertases (PC) to form the disulfide-bonded 125-kDa heavy and 25-kDa light alpha chains. Our report presents evidence of an alternative pathway of pro-alpha(v) processing involving MT1-MMP. In breast carcinoma MCF7 cells deficient in MT1-MMP, pro-alpha(v) is processed by a conventional furin-like PC, and the mature alpha(v) integrin subunit is represented by the 125-kDa heavy chain and the 25-kDa light chain commencing from the N-terminal Asp(891). In contrast, in cells co-expressing alpha(v)beta(3) and MT1-MMP, MT1-MMP functions as an integrin convertase. MT1-MMP specifically cleaves pro-alpha(v), generating a 115-kDa heavy chain with the truncated C terminus and a 25-kDa light chain commencing from the N-terminal Leu(892). PC-cleavable alpha(3) and alpha(5) but not the PC-resistant alpha(2) integrin subunit are also susceptible to MT1-MMP cleavage. These novel mechanisms involved in the processing of integrin alpha subunits underscore the significance and complexity of interactions between MT1-MMP and adhesion receptors and suggest that regulation of integrin functionality may be an important role of MT1-MMP in migrating tumor cells.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

Substances

LinkOut - more resources