Vinculin but not alpha-actinin is a target of PKC phosphorylation during junctional assembly induced by calcium
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Vinculin but not alpha-actinin is a target of PKC phosphorylation during junctional assembly induced by calcium. / Perez-Moreno, M.; Avila, A.; Islas, S.; Sanchez, S.; González-Mariscal, L.
In: Journal of Cell Science, Vol. 111, No. 23, 1998, p. 3563-3571.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Vinculin but not alpha-actinin is a target of PKC phosphorylation during junctional assembly induced by calcium
AU - Perez-Moreno, M.
AU - Avila, A.
AU - Islas, S.
AU - Sanchez, S.
AU - González-Mariscal, L
PY - 1998
Y1 - 1998
N2 - The establishment of the junctional complex in epithelial cells requires the presence of extracellular calcium, and is controlled by a network of reactions involving G-proteins, phospholipase C and protein kinase C. Since potential candidates for phosphorylation are the tight junction associated proteins ZO1, ZO2 and ZO3, in a previous work we specifically explored these molecules but found no alteration in their phosphorylation pattern. To continue the search for the target of protein kinase C, in the present work we have studied the subcellular distribution and phosphorylation of vinculin and alpha-actinin, two actin binding proteins of the adherent junctions. We found that during the junctional sealing induced by Ca2+, both proteins move towards the cell periphery and, while there is a significant increase in the phosphorylation of vinculin, alpha-actinin remains unchanged. The increased phosphorylation of vinculin is due to changes in phosphoserine and phosphothreonine content and seems to be regulated by protein kinase C, since: (1) DiC8 (a kinase C stimulator) added to monolayers cultured without calcium significantly increases the vinculin phosphorylation level; (2) H7 and calphostin C (both protein kinase C inhibitors) completely abolish this increase during a calcium switch; (3) inhibition of phosphorylation during a calcium switch blocks the subcellular redistribution of vinculin and alpha-actinin. These results therefore suggest that vinculin phosphorylation by protein kinase C is a crucial step in the correct assembly of the epithelial junctional complex.
AB - The establishment of the junctional complex in epithelial cells requires the presence of extracellular calcium, and is controlled by a network of reactions involving G-proteins, phospholipase C and protein kinase C. Since potential candidates for phosphorylation are the tight junction associated proteins ZO1, ZO2 and ZO3, in a previous work we specifically explored these molecules but found no alteration in their phosphorylation pattern. To continue the search for the target of protein kinase C, in the present work we have studied the subcellular distribution and phosphorylation of vinculin and alpha-actinin, two actin binding proteins of the adherent junctions. We found that during the junctional sealing induced by Ca2+, both proteins move towards the cell periphery and, while there is a significant increase in the phosphorylation of vinculin, alpha-actinin remains unchanged. The increased phosphorylation of vinculin is due to changes in phosphoserine and phosphothreonine content and seems to be regulated by protein kinase C, since: (1) DiC8 (a kinase C stimulator) added to monolayers cultured without calcium significantly increases the vinculin phosphorylation level; (2) H7 and calphostin C (both protein kinase C inhibitors) completely abolish this increase during a calcium switch; (3) inhibition of phosphorylation during a calcium switch blocks the subcellular redistribution of vinculin and alpha-actinin. These results therefore suggest that vinculin phosphorylation by protein kinase C is a crucial step in the correct assembly of the epithelial junctional complex.
KW - Actinin
KW - Animals
KW - Binding Sites
KW - Calcium
KW - Cell Line
KW - Dogs
KW - Microscopy, Fluorescence
KW - Phosphorylation
KW - Protein Kinase C
KW - Serine
KW - Subcellular Fractions
KW - Threonine
KW - Tight Junctions
KW - Vinculin
KW - Journal Article
KW - Research Support, Non-U.S. Gov't
U2 - 10.1242/jcs.111.23.3563
DO - 10.1242/jcs.111.23.3563
M3 - Journal article
C2 - 9811570
VL - 111
SP - 3563
EP - 3571
JO - Journal of Cell Science
JF - Journal of Cell Science
SN - 0021-9533
IS - 23
ER -
ID: 188369013