The Regulation of Activity of ��-1,4-Galactosyltransferase by Oncogene ras
XU Qin, CHEN Chun, YIN Xiang lei, ZHANG Song wen, GU Jian xin (Gene Research Center,Medical Center of Fudan University,Ministry of Public Health Key Laboratory of Glycoconjugates Research, Shanghai 200032, China)
In order to investigate the regulation of �� 1,4 galactosyltransferase (GalTase) activity by oncogene Ha ras , expression vector of oncogene Ha ras was constructed and transfected into NIH 3T3 cell line. The activities of cell surface and total GalTase activity were assayed by HPLC method. The mRNA of GalTase activity was also evaluated by Northern blot. It was found that the activity of cell surface GalTase was decreased by ras transfection and the enzyme activity of Golgi apparatus remained constant. The mRNA level of GalTase does not be changed by ras . The results showed that the activities of GalTase might be regulated by Ras signal pathway.