Retinoylation of cytokeratins in normal human epidermal keratinocytes.
Retinoylation (retinoic acid acylation) is a covalent modification of proteins occurring in a variety of eukaryotic cell lines. In this study, we found that proteins in undifferentiated and squamous-differentiated normal human epidermal keratinocytes were retinoylated after treatment with [3H]retinoic acid. The major retinoylated proteins were identified as cytokeratins based on their profile in two-dimensional gel electrophoresis and their immunoreactivity with anti-keratin monoclonal antibodies. The covalently bound [3H]retinoic acid was not removed by mild hydrolysis with methanolic-KOH indicating that it is not linked to the cytokeratins by a thioester bond. The results raise the possibility that retinoylation of cytokeratins is involved in some of the effects of retinoic acid on keratinocytes.
Takahashi
N
N
Laboratory of Biological Chemistry, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892.
Jetten
A M
AM
Breitman
T R
TR
D000215:Acylation; D000911:Antibodies, Monoclonal; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D002478:Cells, Cultured; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D015151:Immunoblotting; D015603:Keratinocytes / Q000378:metabolism*; D007633:Keratins / Q000378:metabolism*; D014212:Tretinoin / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D014212:Tretinoin; D007633:Keratins