β-1,4- galactosyltransferase 1 (β1,4-GT 1) is localized both in the Golgi complex where it catalyzes the transfer of galactose from UDP-galactose to terminal N-acetylglucosamine forming Galβ1→4GlcNAc structure, and on the cell surface where it serves as an adhesion molecule. It has previously been reported that the expression of β1,4-GT 1 was cell-cycle-specific, regulated by cell growth. Transforming growth factor-β1 (TGF-β1) could regulate cell G1/S phase transition and modulate cell growth in many types of cells. In this study, we introduced the antisense-TGF-β1 into SMMC-7721 cell, a human hepatocarcinoma cell line, for blocking its intrinsic TGF-β1 expression, and changing its cell-cycle, and then analyzed the gene expression of β1,4-GT 1 together with the β1,4-GT activity. The result showed that the antisense-TGF-β1 transfected SMMC-7721 cells (AST/7721) were growth enhanced, with more cells in S phase and less cells in G2/M phase compared with the mock transfected cells (pcDNA3/7721). At the same time, it was found that the gene expression of β1,4-GT 1 in AST/7721 was decreased to one fifth that of pcDNA3/7721, and the cell surface β1,4-GT activity was reduced to one fifth of the control, while the total activity of β1,4-GT was decreased to one half that of the control. The results indicate that suppression of TGF-β1 expression resulted in change of cell-cycle together with the decreased gene expression of β1,4-GT 1 and β1,4-GT activity in human hepatocarcinoma cells. (C) 2000 Academic Press.
|Original language||English (US)|
|Number of pages||6|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Jul 14 2000|
Bibliographical noteFunding Information:
This work is supported by the National Natural Scientific Grants (39870168, 39630080), People’s Republic of China. We thank Dr. Kiyoshi Furukawa, Tokyo Metropolitan Institute of Gerontology, Japan, for his constructive suggestions on the manuscript.
- Antisense TGF-β1
- Cell cycle
- β-1,4-galactosyltransferase 1