Mouse beta 1,3-galactosyltransferase (GA1/GM1/GD1b synthase): protein characterization, tissue expression, and developmental regulation in neural retina

DANIOTTI J.L.; MARTINA J. A.; ZURITA A.R.; MACCIONI H.J.F.

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 1999 vol. 58 p. 318 - 318

he composition of cell surface gangliosides is largely dependent on the relative activities of Golgi resident glycosyltransferases. In the brain of birds and mammals, complex gangliosides (GM2, GM1, GD1a, GD1b, GT1b) abound at late stages of development and in the adult, due to the relatively high activities of the UDP-GalNAc:LacCer/GM3/GD3 beta 1,4-N-acetylgalactosaminyltransferase (GalNAc-T) and the UDP-Gal: GA2/GM2/GD2 beta 1, 3-galactosyltransferase (Gal-T2) relative to that of CMP-NeuAc:GM3 alpha 2,8-sialyltransferase (Sial-T2). Unlike brain, the mature mammalian neural retina abundantly expresses the simple ganglioside GD3, in relation to complex gangliosides, due to the low activity of GalNAc-T and Gal-T2 relative to Sial-T2. Here we describe the isolation and characterization of a mouse Gal-T2 cDNA that drives the synthesis of an epitope-tagged protein of molecular mass 43 kDa, which was enzymatically active and localized to the Golgi complex in transfected cell lines. Using t