Ubiquitin receptors and protein quality control

► Protein quality control minimizes the level and toxicity of misfolded proteins. ► Failing human hearts often display protein quality control inadequacy. ► Substrate delivery to the proteasome appears to be deficient in diseased hearts. ► Ubiquitin receptors help deliver ubiquitinated proteins to the proteasome. ► The role of ubiquitin receptors in cardiac (patho)physiology is yet to be defined.