FBXL21 regulates diurnal proteostasis in skeletal muscle by targeting DNAJB6 and client proteins.
Circadian regulation of proteostasis, a key determinant of muscle health, remains poorly understood. Here, we identify DNAJB6, an Hsp40 (DnaJ) co-chaperone, as a substrate of the circadian E3 ligase FBXL21. FBXL21 mediates the ubiquitination-dependent proteasomal degradation of both DNAJB6 and its client proteins, incl...