The SH3 domain of the tight junction protein ZO-1 binds to a serine protein kinase that phosphorylates a region C-terminal to this domain.
ZO-1 is a tight junction phosphoprotein partially homologous to a tumor suppressor in Drosophila. The homologous region contains an SH3 domain with an unidentified function. Using fusion proteins containing the SH3 domain and various N- and C-terminal sequences, we tested for association of a kinase with this protein domain in extracts of MDCK cells. We show that the SH3 domain of ZO-1 binds a serine protein kinase that phosphorylates a region immediately C-terminal to the SH3 domain. This kinase associates specifically with the SH3 domain of ZO-1 and appears to be also associated with junctional complexes extracted from MDCK cells.
Balda
M S
MS
Department of Cell Biology, Science III, University of Geneva, Switzerland. Maria.Balda@cellbiol.unige.ch
Anderson
J M
JM
Matter
K
K
D000818:Animals; D002460:Cell Line; D004285:Dogs; D005982:Glutathione Transferase / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D011233:Precipitin Tests; D011485:Protein Binding; D011494:Protein Kinases / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D062826:Zonula Occludens-1 Protein; D018909:src Homology Domains
D008565:Membrane Proteins; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; D062826:Zonula Occludens-1 Protein; D005982:Glutathione Transferase; D011494:Protein Kinases