Trafficking and localisation of resident Golgi glycosylation enzymes

The localisation of glycosylation enzymes within the Golgi apparatus is fun damental to the regulation of glycoprotein and glycolipid biosynthesis. Reg ions responsible for specifying Golgi localisation have been identified in numerous Golgi resident enzymes. The transmembrane domain of Golgi glycosyl transferases provides a dominant localisation signal and in many cases ther e are also major contributions from the lumenal domain. The mechanism by wh ich these targeting domains function in maintaining an asymmetric distribut ion of Golgi resident glycosylation enzymes has been intensely debated in r ecent years. It is now clear that the targeting of Golgi resident enzymes i s intimately associated with the organisation of Golgi membranes and the co ntrol of protein and lipid traffic in both anterograde and retrograde direc tions. Here we discuss the recent advances into how Golgi targeting signals of glycosylation enzymes function, and propose a model for maintaining the steady-state localisation of Golgi glycosyltransferases. (C) 2001 Societe francaise de biochimie et biologic moleculaire/Editions scientifiques et me dicales Elsevier SAS. All rights reserved.