The functions of integrins are tightly regulated via multiple mechanisms including trafficking and degradation. Integrins are repeatedly internalized, routed into the endosomal system and either degraded by the lysosome or recycled back to the plasma membrane. The ubiquitin system dictates whether internalized proteins are degraded or recycled. Here, we use a genetic screen and proximity-dependent biotin identification to identify deubiquitinase(s) that control integrin surface levels. We find that a ternary deubiquitinating complex, comprised of USP12 (or the homologous USP46), WDR48 and WDR20, stabilizes β1 integrin (Itgb1) by preventing ESCRT-mediated lysosomal degradation. Mechanistically, the USP12/46-WDR48-WDR20 complex removes ubiquitin from the cytoplasmic tail of internalized Itgb1 in early endosomes, which in turn prevents ESCRT-mediated sorting and Itgb1 degradation.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11624278 | PMC |
http://dx.doi.org/10.1038/s44319-024-00300-9 | DOI Listing |
EMBO Rep
December 2024
Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany.
The functions of integrins are tightly regulated via multiple mechanisms including trafficking and degradation. Integrins are repeatedly internalized, routed into the endosomal system and either degraded by the lysosome or recycled back to the plasma membrane. The ubiquitin system dictates whether internalized proteins are degraded or recycled.
View Article and Find Full Text PDFRes Sq
May 2024
Department of Biology, Stanford University, Stanford, California, USA.
Aging is a prominent risk factor for Alzheimer's disease (AD), but the cellular mechanisms underlying neuronal phenotypes remain elusive. Both accumulation of amyloid plaques and neurofibrillary tangles in the brain and age-linked organelle deficits are proposed as causes of AD phenotypes but the relationship between these events is unclear. Here, we address this question using a transdifferentiated neuron (tNeuron) model directly from human dermal fibroblasts.
View Article and Find Full Text PDFJ Cell Biol
April 2024
Weill Institute for Cell and Molecular Biology and Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.
Endosomes are specialized organelles that function in the secretory and endocytic protein sorting pathways. Endocytosed cell surface receptors and transporters destined for lysosomal degradation are sorted into intraluminal vesicles (ILVs) at endosomes by endosomal sorting complexes required for transport (ESCRT) proteins. The endosomes (multivesicular bodies, MVBs) then fuse with the lysosome.
View Article and Find Full Text PDFJ Mol Med (Berl)
March 2024
Quantlase Imaging Laboratory, Quantlase Lab LLC, Unit 1-8, Masdar City, Abu Dhabi, UAE.
Lysosomes function as critical signaling hubs that govern essential enzyme complexes. LGALS proteins (LGALS3, LGALS8, and LGALS9) are integral to the endomembrane damage response. If ESCRT fails to rectify damage, LGALS-mediated ubiquitination occurs, recruiting autophagy receptors (CALCOCO2, TRIM16, and SQSTM1) and VCP/p97 complex containing UBXN6, PLAA, and YOD1, initiating selective autophagy.
View Article and Find Full Text PDFNat Commun
November 2023
Institute of Molecular Medicine, College of Medicine, National Taiwan University, 10002, Taipei, Taiwan.
Ligand-induced epidermal growth factor receptor (EGFR) endocytosis followed by endosomal EGFR signaling and lysosomal degradation plays important roles in controlling multiple biological processes. ADP-ribosylation factor (Arf)-like protein 4 A (Arl4A) functions at the plasma membrane to mediate cytoskeletal remodeling and cell migration, whereas its localization at endosomal compartments remains functionally unknown. Here, we report that Arl4A attenuates EGFR degradation by binding to the endosomal sorting complex required for transport (ESCRT)-II component VPS36.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!