Functions of the alpha, beta, and gamma subunits of UDP-GlcNAc:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase.

ABSTRACT: UDP-GlcNAc:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase is an alpha(2)beta(2)gamma(2) hexamer that mediates the first step in the synthesis of the mannose 6-phosphate recognition marker on lysosomal acid hydrolases. Using a multifaceted approach, including analysis of acid hydrolase phosphorylation in mice and fibroblasts lacking the gamma subunit along with kinetic studies of recombinant alpha(2)beta(2)gamma(2) and alpha(2)beta(2) forms of the transferase, we have explored the function of the alpha/beta and gamma subunits. The findings demonstrate that the alpha/beta subunits recognize the protein determinant of acid hydrolases in addition to mediating the catalytic function of the transferase. In mouse brain, the alpha/beta subunits phosphorylate about one-third of the acid

SUBMITTER: Qian Y 

PROVIDER: S-EPMC2823453 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature