Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:2.4.99.6 (
sialyltransferase
)
1,546
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Although disialyl glycosphingolipids such as GD3 and GD2 have been considered to be associated with malignant tumours, whether branched-type disialyl glycosphingolipids show such an association is not well understood. We investigated the sialyltransferases responsible for the biosynthesis of
DSGG
(disialylgalactosylgloboside) from MSGG (monosialylgalactosylgloboside). Among six GalNAc:alpha2,6-sialyltransferases cloned to date, we focused on ST6GalNAc III, V and VI, which utilize sialylglycolipids as substrates. In vitro enzyme analyses revealed that ST6GalNAc III and VI generated
DSGG
from MSGG with V(max)/K(m) values of 1.91 and 4.16 respectively. Transfection of the cDNA expression vectors for these enzymes resulted in
DSGG
expression in a renal cancer cell line. Although both ST6GalNAc III and VI genes were expressed in normal kidney cells, the expression profiles of ST6GalNAc VI among 20 renal cancer cell lines correlated clearly with those of
DSGG
, suggesting that the
sialyltransferase
involved in the synthesis of
DSGG
in the kidney is ST6GalNAc-VI. ST6GalNAc-VI and
DSGG
were found in proximal tubule epithelial cells in normal kidney tissues, while they were downregulated in renal cancer cell lines and cancer tissues. All these findings indicated that
DSGG
was suppressed during the malignant transformation of the proximal tubules as a maturation arrest of glycosylation.
...
PMID:Identification and expression of a sialyltransferase responsible for the synthesis of disialylgalactosylgloboside in normal and malignant kidney cells: downregulation of ST6GalNAc VI in renal cancers. 1712 52
