Stabilization of plakoglobin and enhanced keratinocyte cell-cell adhesion by intracellular O-glycosylation

Department of Dermatology, University of North Carolina, Chapel Hill, North Carolina 27599-7287, USA.
Journal of Biological Chemistry (Impact Factor: 4.6). 06/2006; 281(18):12786-91. DOI: 10.1074/jbc.M511702200
Source: PubMed

ABSTRACT O-Glycosylation modifies and regulates a variety of intracellular proteins. Plakoglobin, which functions in both cell-cell adhesion and signal transduction, is modified by O-glycosylation; however, the significance is unknown. To investigate the functional consequence of plakoglobin O-glycosylation, we cloned and overexpressed in keratinocytes murine O-GlcNAc transferase (mOGT). Over expression of mOGT in murine keratinocytes resulted in (i) glycosylation of plakoglobin and (ii) increased levels of plakoglobin due to post-translational stabilization of plakoglobin. Additionally, overexpression of mOGT in keratinocytes correlated with increased staining for cell-cell adhesion proteins and greater cell-cell adhesion. These observations suggest that O-glycosylation functions to regulate the post-translational stability of plakoglobin and keratinocyte cell-cell adhesion.

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