Hijacking ZIP codes: posttanscriptional regulation of CCN2 by nucleophosmin

CCN2 (connective tissue growth factor [CTGF]/hypertrophic chondrocyte-specific gene product 24 [Hcs24]) is regulated at the transcriptional and posttranscriptional level. For example, an element in the its 3' untranslated region (3'-UTR) of the CCN2 mRNA controls message stability in chondrocytes. In a recent study, Mukudai et al. (Mol Cell Biol 28:6134-6147, 2008) purified and identified a trans-factor protein binding to the minimal repressive cis element in the 3'-UTR of ccn2 mRNA and identify this protein as the multifunctional nucleolar phosphoprotein nucleophosmin (NPM) This commentary summarizes these observations.