REGgamma: a shortcut to destruction.

Department of Pathology and Laboratory Medicine, Weill Medical College and Graduate School of Medical Sciences of Cornell University, New York, NY 10021, USA.
Cell (Impact Factor: 33.12). 02/2006; 124(2):256-7. DOI: 10.1016/j.cell.2006.01.003
Source: PubMed

ABSTRACT Destruction of intact cellular proteins is largely orchestrated by ATP-dependent ubiquitination and subsequent degradation by the 26S proteasome. The REG-20S proteasome, however, only degrades short peptides. In this issue of Cell, challenge this notion by revealing that the proteasomal activator REGgamma directs degradation of the steroid receptor coactivator SRC-3 by the 20S proteasome in an ATP- and ubiquitin-independent manner.

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