BLTP3A is associated with membranes of the late endocytic pathway and is an effector of CASM Journal Article


Authors: Hanna, M. G.; Rodriguez Cruz, H. O.; Fujise, K.; Wu, Y.; Xu, C. S.; Pang, S.; Li, Z.; Monetti, M.; De Camilli, P.
Article Title: BLTP3A is associated with membranes of the late endocytic pathway and is an effector of CASM
Abstract: <p>Recent studies have identified a family of rod-shaped proteins thought to mediate lipid transfer at intracellular membrane contacts by a bridge-like mechanism. We show that one such protein, bridge-like lipid transfer protein 3A (BLTP3A)/UHRF1BP1 binds VAMP7 vesicles via its C-terminal region, and anchors them to lysosomes via its chorein domain-containing N-terminal region binding to Rab7. Upon lysosome damage, BLTP3A-positive vesicles rapidly (within minutes) dissociate from lysosomes. Lysosome damage is known to activate the CASM (Conjugation of ATG8 to Single Membranes) pathway, leading to lipidation and lysosomal recruitment of mammalian ATG8 (mATG8) proteins. We find that this process drives the reassociation of BLTP3A with damaged lysosomes via an interaction of its LIR motif with mATG8 which coincides with a dissociation from the vesicles. Our findings reveal that BLTP3A is an effector of CASM, potentially as part of a mechanism to help repair or minimize lysosome damage.</p>
Keywords: binding protein; autophagy; lysosome; mechanism; endoplasmic-reticulum; lc3; endosomes; contact sites; myosin va; trans-golgi network; bltp3; rab45; urate crystals; links rab27a; uhrf1bp1
Journal Title: EMBO Journal
ISSN: 0261-4189
Publisher: Wiley Blackwell  
Publication status: Online ahead of print
Date Published: 2025-09-11
Online Publication Date: 2025-09-11
Language: English
ACCESSION: WOS:001568692600001
DOI: 10.1038/s44318-025-00543-9
PROVIDER: wos
PUBMED: 40935891
Notes: Article; Early Access -- MSK Cancer Center Support Grnat (P30 CA008748) acknowledged in PDF -- MSK author Zhuoning Li's first name is misspelled on the original publication -- Source: Wos
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MSK Authors
  1. Zhuoning Li
    24 Li
  2. Mara Monetti
    10 Monetti