Proteasome heterogeneity in cardiac tissue

The ubiquitin–proteasome pathway is the major source for non-lysosomal protein degradation and participates in regulation of various key cellular events. Recent identification of cardiac proteasome subunits in our laboratory suggested proteasome heterogeneity in murine hearts (Circ Res. 2006; 99:362–71). Proteasome inhibitors aggravate as well as impair the malicious effects of cardiac ischemia in animal models, which might be related to proteasome heterogeneity.