Regulation of the expression and activity of beta1,4-galactosyltransferase I by focal adhesion kinase.
beta1,4-Galactosyltransferase I (GalT) participates in both glycoconjugates and cellular interactions. GalT's role in lamellipodia formation and cell migration on laminin is associated with a transient phosphorylation of focal adhesion kinase (FAK) and a consequent reorganization of the actin cytoskeleton and focal adhesions. We transfected wild type FAK and different FAK mutants into NIH3T3 cell line, measured GalT gene expression by Northern blot hybridization, and evaluated its activity. It was found that wtFAK and FAKY576F up-regulated GalT gene expression and its surface activity, while FAKY397F down-regulated them. At the same time, we used ricinus communis agglutinin (RCA)-I lectin staining to demonstrate its binding reactions. We found that wtFAK and FAKY576F bound stronger, while FAKY397F bound weaker than the control. By flow cytometry analysis, it was found that FAK promoted G1/S transition and enhanced the expression of cyclin D1 while FAKY397F inhibited these steps compared with the control NIH3T3 cells. G1/S checkpoint regulation proteins control GalT mRNA transcription. The results indicate that FAK regulated the expression of GalT and its activity in NIH3T3 cells may contribute to the effect of FAK on the cell-cycle.
Ji
Shu Y
SY
Gene Research Center, Medical Center of Fudan University, Shanghai, PR China.
Zhu
Xiao Y
XY
Chen
She
S
Shen
Ai G
AG
Yin
Xiang L
XL
Chen
Chun
C
Yao
Lu Y
LY
Gu
Jian X
JX
D000818:Animals; D002453:Cell Cycle / Q000502:physiology; D005434:Flow Cytometry; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; D005700:Galactosyltransferases / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D051379:Mice; D041681:NIH 3T3 Cells; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000502:physiology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014162:Transfection
D012333:RNA, Messenger; D005700:Galactosyltransferases; C119701:beta-1,4-galactosyltransferase I; D011505:Protein-Tyrosine Kinases; D051417:Focal Adhesion Kinase 1; D051416:Focal Adhesion Protein-Tyrosine Kinases; C496051:Ptk2 protein, mouse