The ubiquitin-conjugating enzyme UBE2QL1 coordinates lysophagy in response to endolysosomal damage.
EMBO Rep
; 20(10): e48014, 2019 10 04.
Article
em En
| MEDLINE
| ID: mdl-31432621
ABSTRACT
The autophagic clearance of damaged lysosomes by lysophagy involves extensive modification of the organelle with ubiquitin, but the underlying ubiquitination machinery is still poorly characterized. Here, we use an siRNA screening approach and identify human UBE2QL1 as a major regulator of lysosomal ubiquitination, lysophagy, and cell survival after lysosomal damage. UBE2QL1 translocates to permeabilized lysosomes where it associates with damage sensors, ubiquitination targets, and lysophagy effectors. UBE2QL1 knockdown reduces ubiquitination and accumulation of the critical autophagy receptor p62 and abrogates recruitment of the AAA-ATPase VCP/p97, which is essential for efficient lysophagy. Crucially, it affects association of LC3B with damaged lysosomes indicating that autophagosome formation was impaired. Already in unchallenged cells, depletion of UBE2QL1 leads to increased lysosomal damage, mTOR dissociation from lysosomes, and TFEB activation pointing to a role in lysosomal homeostasis. In line with this, mutation of the homologue ubc-25 in Caenorhabditis elegans exacerbates lysosome permeability in worms lacking the lysosome stabilizing protein SCAV-3/LIMP2. Thus, UBE2QL1 coordinates critical steps in the acute endolysosomal damage response and is essential for maintenance of lysosomal integrity.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Endossomos
/
Autofagia
/
Enzimas de Conjugação de Ubiquitina
/
Lisossomos
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
EMBO Rep
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Alemanha