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Updated: Sep 18, 2026

Mass Spectrometry Analysis to Identify Ubiquitylation of EYFP-tagged CENP-A (EYFP-CENP-A)
Published on: June 10, 2020
Spatial control of mitochondrial ubiquitination by the AMBRA1-RMC1-HUWE1 axis
Jiamin Yi1, Xin Yong1, Da Jia1
1Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, West China Second University Hospital, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, China.
Abstract:
Mitochondrial ubiquitination is a central component of mitochondrial quality control. The PINK1 (PTEN induced kinase 1)-PRKN (parkin RBR E3 ubiquitin protein ligase) pathway established how loss of mitochondrial membrane potential can trigger a phospho-ubiquitin feed-forward cascade on the outer mitochondrial membrane (OMM). It remains less clear how mitochondrial ubiquitination is achieved when PRKN is absent or inactivated. In our recent work, we identify a recruitment platform organized by AMBRA1 (autophagy and beclin 1 regulator 1), in which RMC1 (regulator of MON1-CCZ1) positions HUWE1 (HECT, UBA and WWE domain containing E3 ubiquitin protein ligase 1) at mitochondria. This spatial arrangement promotes HUWE1-dependent ubiquitination and turnover of OMM proteins, including MFN2 (mitofusin 2), VDAC1 (voltage-dependent anion channel 1), and VDAC2 (voltage-dependent anion channel 2). Our findings raise the question of how cells select among distinct mitochondrial ubiquitination pathways and whether these pathways function independently, sequentially, or cooperatively.
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