ALS-linked loss of Cyclin-F function affects HSP90

Siebert, Alexander; Gattringer, Vanessa; Weishaupt, Jochen H.; Behrends, Christian (2022): ALS-linked loss of Cyclin-F function affects HSP90. Life Science Alliance, 5 (12): e202101359. ISSN 2575-1077

Abstract

The founding member of the F-box protein family, Cyclin-F, serves as a substrate adaptor for the E3 ligase Skp1-Cul1-F-box (SCF)Cyclin-F which is responsible for ubiquitination of proteins involved in cell cycle progression, DNA damage and mitotic fidelity. Missense mutations in CCNF encoding for Cyclin-F are associated with amyotrophic lateral sclerosis (ALS). However, it remains elusive whether CCNF mutations affect the substrate adaptor function of Cyclin-F and whether altered SCFCyclin-F–mediated ubiquitination contributes to pathogenesis in CCNF mutation carriers. To address these questions, we set out to identify new SCFCyclin-F targets in neuronal and ALS patient–derived cells. Mass spectrometry–based ubiquitinome profiling of CCNF knockout and mutant cell lines as well as Cyclin-F proximity and interaction proteomics converged on the HSP90 chaperone machinery as new substrate candidate. Biochemical analyses provided evidence for a Cyclin-F–dependent association and ubiquitination of HSP90AB1 and implied a regulatory role that could affect the binding of a number of HSP90 clients and co-factors. Together, our results point to a possible Cyclin-F loss-of-function–mediated chaperone dysregulation that might be relevant for ALS.

• Doc-Type: Article (LMU)
• Organisational unit (Faculties): 07 Medicine > Munich Cluster for Systems Neurology (SyNergy)
• DFG subject classification of scientific disciplines: Life sciences
• DFG: Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - 390857198
• DFG: Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - 491502892