Regulated permeability of tight junctions by E-cadherin in rat submandibular gland acini.
We examined the relationship between E-cadherin (E-CD), protein kinase C (PKC) and assembly of the tight junction (Tj) in rat submandibular gland acinar cells. The junctional complex of the acinar cells was double-labeled with anti-ZO-1 antibody and anti-E-CD antibody. When Ringer's solution was intraductally injected into the main duct, ZO-1 labels were highly concentrated at the Tj zone, and the adherens junction (Aj) was exclusively labeled by E-CD. In addition, the Tj was impermeable to microperoxidase. Neither intraductal injection of anti-E-CD antibody solution nor infusion of carbachol produced labels for ZO-1 at the Tj zone, although these proteins were occasionally intermixed at the Aj zone. In these cases, the Tj was permeable to microperoxidase. Intraductal injection of anti-E-CD antibody solution with PKC agonist, resulted in a reduction of E-CD labels in the Aj zone, while the ZO-1 was labeled exclusively in the Tj zone. In this case, Tj was impermeable to microperoxidase. These results suggest that E-CD plays a major role in mediating intercellular physical adhesion, and that PKC may be active in signaling the pathway activated by E-CD-mediated cell-cell adhesion.
Murakami
H
H
Department of Physiology, Osaka Dental University, Japan.
Uchihashi
K
K
Yoshida
Y
Y
D000818:Animals; D015820:Cadherins / Q000378:metabolism*; D002448:Cell Adhesion / Q000502:physiology*; D002463:Cell Membrane Permeability; D003598:Cytoskeletal Proteins / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013363:Submandibular Gland / Q000166:cytology* / Q000378:metabolism; D019108:Tight Junctions / Q000378:metabolism*; D062826:Zonula Occludens-1 Protein; D051178:alpha Catenin
D015820:Cadherins; D003598:Cytoskeletal Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; C569044:Tjp1 protein, rat; D062826:Zonula Occludens-1 Protein; D051178:alpha Catenin