The protein kinase C activator TPA modulates cellular levels and distribution of E-cadherin in HT-29 human intestinal epithelial cells.
The importance of E-cadherin protein in the establishment and maintenance of homotypic contacts in epithelial cells has already been determined. We report here that the association of E-cadherin to cytoskeleton, required for the functionality of this protein, increases progressively after seeding; in HT-29 M6 cells 4-5 days were required for detecting most of E-cadherin in the Triton X-100-insoluble (cytoskeleton-associated) fraction. The phorbol ester TPA differently affected E-cadherin levels in HT-29 M6 cells; at day 2-3, when most E-cadherin was found not-associated to the cytoskeleton, very important decreases (90%) in the total levels of this protein were detected as soon as 6 h after the addition of this compound. However, on later days (day 5), the predominant effect by 6 h was a translocation from the Triton-insoluble to the soluble fraction. The E-cadherin-associated proteins alpha-catenin and beta-catenin were not significantly affected by treatment with TPA.
Skoudy
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Department d'Immunologia, Universitat Autònoma de Barcelona, Spain.
García de Herreros
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D015820:Cadherins / Q000378:metabolism*; D002460:Cell Line; D003598:Cytoskeletal Proteins / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000187:drug effects / Q000648:ultrastructure; D011493:Protein Kinase C / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D013997:Time Factors; D015534:Trans-Activators; D051178:alpha Catenin; D051176:beta Catenin
C495273:CTNNA1 protein, human; C495270:CTNNB1 protein, human; D015820:Cadherins; D003598:Cytoskeletal Proteins; D015534:Trans-Activators; D051178:alpha Catenin; D051176:beta Catenin; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate