The ubiquitination of mitochondrial proteins labels damaged mitochondria for degradation through mitophagy. We recently developed an system in which mitophagy is slowed by inhibiting mitochondrial division through knockout of , a dynamin related GTPase that mediates mitochondrial division. Using this system, we revealed that the ubiquitination of mitochondrial proteins required SQSTM1/p62, but not the ubiquitin E3 ligase PRKN/parkin, during mitophagy. Here, we tested the role of PINK1, a mitochondrial protein kinase that activates mitophagy by phosphorylating ubiquitin, in mitochondrial ubiquitination by knocking out in -knockout liver. We found mitochondrial ubiquitination did not decrease in the absence of PINK1; instead, PINK1 was required for the degradation of MFN1 (mitofusin 1) and MFN2, two homologous outer membrane proteins that mediate mitochondrial fusion in -knockout hepatocytes. These data suggest that mitochondrial ubiquitination is promoted by SQSTM1 independently of PINK1 and PRKN during mitophagy. PINK1 and PRKN appear to control the balance between mitochondrial division and fusion . DNM1L/DRP1: dynamin 1-like; KEAP1: kelch-like ECH-associated protein 1; KO: knockout; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MFN1/2: mitofusin 1/2; OPA1: OPA1, mitochondrial dynamin like GTPase; PDH: pyruvate dehydrogenase E1; PINK1: PTEN induced putative kinase 1; PRKN/parkin: parkin RBR E3 ubiquitin protein ligase.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6844492 | PMC |
| http://dx.doi.org/10.1080/15548627.2019.1643185 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Molecular Symphony of Mitophagy: Ubiquitin-Specific Protease-30 as a Maestro for Precision Management of Neurodegenerative Diseases.
CNS Neurosci Ther
January 2025
Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, USA.
Introduction: Mitochondrial dysfunction stands as a pivotal feature in neurodegenerative disorders, spurring the quest for targeted therapeutic interventions. This review examines Ubiquitin-Specific Protease 30 (USP30) as a master regulator of mitophagy with therapeutic promise in Alzheimer's disease (AD) and Parkinson's disease (PD). USP30's orchestration of mitophagy pathways, encompassing PINK1-dependent and PINK1-independent mechanisms, forms the crux of this exploration.
View Article and Find Full Text PDFDeletion of Pyruvate Carboxylase in Tubular Epithelial Cell Promotes Renal Fibrosis by Regulating SQOR/cGAS/STING-Mediated Glycolysis.
Adv Sci (Weinh)
January 2025
Department of Nephrology, Xiangya Hospital, Central South University, Changsha, 410008, China.
Renal fibrosis is a common pathway involved in the progression of various chronic kidney diseases to end-stage renal disease. Recent studies show that mitochondrial injury of renal tubular epithelial cells (RTECs) is a crucial pathological foundation for renal fibrosis. However, the underlying regulatory mechanisms remain unclear.
View Article and Find Full Text PDFMitoStores: stress-induced aggregation of mitochondrial proteins.
Biol Chem
January 2025
Cell Biology, 26562 RPTU University of Kaiserslautern, Erwin-Schrödinger-Strasse 13, D-67663 Kaiserslautern, Germany.
Most mitochondrial proteins are synthesized in the cytosol and post-translationally imported into mitochondria. If the rate of protein synthesis exceeds the capacity of the mitochondrial import machinery, precursor proteins can transiently accumulate in the cytosol. The cytosolic accumulation of mitochondrial precursors jeopardizes cellular protein homeostasis (proteostasis) and can be the cause of diseases.
View Article and Find Full Text PDFInducers of Autophagy and Cell Death: Focus on Copper Metabolism.
Ecotoxicol Environ Saf
January 2025
State Key Laboratory of Swine and Poultry Breeding Industry, Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province, College of Animal Science and Technology, Sichuan Agricultural University, Chendu 611130, PR China. Electronic address:
Copper is an essential trace element in biological systems, playing a key role in various physiological functions, including redox reactions and energy metabolism. However, an imbalance in copper homeostasis can induce oxidative stress, mitochondrial dysfunction, and inhibition of the ubiquitin-proteasome system, ultimately leading to significant cytotoxicity and cell death. According to recent research, copper can bind to lipoylation sites on proteins involved in the tricarboxylic acid cycle, causing aggregation of lipoylated proteins, the loss of Fe-S cluster proteins, proteotoxic stress, and ultimately, cell death.
View Article and Find Full Text PDFSquamocin Suppresses Tumor Growth through Triggering an Endoplasmic Reticulum Stress-Associated Degradation of EZH2/MYC Axis.
Adv Sci (Weinh)
January 2025
School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, 510515, China.
Despite substantial advances in the antitumor effects of annonaceous acetogenins (ACGs), the absence of a defined biological action mechanism remains a major barrier to their clinical application. Here, it is found that squamocin effectively depletes both EZH2 and MYC in multiple cancer cell lines, including head and neck squamous cell carcinoma, and gastric and colorectal cancer, demonstrating potent efficacy in suppressing these in vivo tumor models. Through the combination of surface plasmon resonance (SPR), differential scanning fluorimetry (DSF), and cellular thermal shift assay (CETSA), heat shock protein 90α (HSP90α) is identified as the direct binding target of squamocin.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!