Quality control of protein complex assembly by the ubiquitin–proteasome system

The majority of human proteins function as part of multimeric protein complexes.Subunit stoichiometry in vivo is highly variable, and a significant fraction of the proteome arises from non-stoichiometric synthesis.The ubiquitin–proteasome system (UPS) can detect failures in complex assembly and target unassembled or incorrectly assembled complexes for degradation.Key cellular complexes such as hemoglobin, BTB (broad complex, Tramtrack, and Bric-à-brac) dimers, the proteasome, and the ribosome have recently been shown to undergo assembly quality cellular function and The majority of human proteins as multimeric complexes and the assembly of complexes is and complexes is to part of the ubiquitin–proteasome system (UPS) in target proteins and The recently been shown to quality the assembly of protein protein complex assembly and to of The majority of human proteins as multimeric complexes and the assembly of complexes is and complexes is to part of the ubiquitin–proteasome system (UPS) in 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