Characterization of the dimerization interface of membrane type 4 (MT4)-matrix metalloproteinase.

ABSTRACT: MT4-MMP (MMP17) belongs to a unique subset of membrane type-matrix metalloproteinases that are anchored to the cell surface via a glycosylphosphatidylinositol moiety. However, little is known about its biochemical properties. Here, we report that MT4-MMP is displayed on the cell surface as a mixed population of monomeric, dimeric, and oligomeric forms. Sucrose gradient fractionation demonstrated that these forms of MT4-MMP are all present in lipid rafts. Mutational and computational analyses revealed that Cys(564), which is present within the stem region, mediates MT4-MMP homodimerization by forming a disulfide bond. Substitution of Cys(564) results in a more rapid MT4-MMP turnover, when compared with the wild-type enzyme, consistent with a role for dimerization in protein stability. Expre

SUBMITTER: Sohail A 

PROVIDER: S-EPMC3190889 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature