alpha-N-acetylgalactosaminide alpha-2,6-sialyltransferase 6 (galNAc alpha-2,6-sialyltransferase VI, ST6galNAc VI, hST6galNAc VI, sialyltransferase 7F, ST6GALNAC6, SIAT7F, UNQ708/PRO1359)

Function

• alpha-2,6-sialyltransferase involved in the synthesis of alpha-series gangliosides
• activity toward GD1a, GT1b & GM1b
• no activity toward glycoproteins
• responsible for biosynthesis of disialylgalactosylgloboside (DSGG) from monosialylgalactosylgloboside (MSGG) in normal & malignant kidney

Kinetic parameters:

• KM=0.33 mM for GM1b
• KM=0.46 mM for sialyl-Lc4

Structure

belongs to the glycosyltransferase 29 family

Compartment

• Golgi membrane

Alternative splicing

named isoforms=2

Expression

• expressed in kidney, in proximal tubule epithelial cells

Pathology

• expressed in colon cell lines
• down-regulated in renal cancers
• participates in the synthesis of disialyl Lewis a (Le(a)), a representative tumor-associated antigen in cancers of the pancreas & colon, in colon tissues

More general terms

• sialyltransferase
• glycoprotein
• membrane protein

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:3081
• UniProt: http://www.uniprot.org/uniprot/Q969X2.html