?1?4-galactosyltransferase gene expression is regulated during entry into the cell cycle and during the cell cycle

Abstract

Mammalian glycosyltransferases have been implicated in a wide variety of functions besidesN-linked glycosylation, including developmental processes. For this reason, we studied the effects of cell cycle and entry into the cell cycle on β1–4-galactosyltransferase gene expression. In this study we report that β1–4-galactosyltransferase (GalTase) gene expression is, indeed, regulated during the normal cell cycle, peaking during late G₁-, S, and early G₂ phase of the cell cycle. In addition, GalTase gene expression is regulated in a manner that resembles other “early response” genes such asjun andfos upon reentry into the cell cycle from quiescence. Finally, we show that the GalTase gene is differentially expressed during murine embryogenesis and in terminally differentiated adult tissues. It is most abundant in testis, followed by skeletal muscle and spleen. The reasons for this pattern of differential expression in adult tissues are unknown. These studies should provide important new information regarding GalTase gene expression, its regulation, and its potential link to other developmental functions.