Cargando…

A heterodimeric SNX4­–SNX7 SNX-BAR autophagy complex coordinates ATG9A trafficking for efficient autophagosome assembly

The sorting nexins (SNXs) are a family of peripheral membrane proteins that direct protein trafficking decisions within the endocytic network. Emerging evidence in yeast and mammalian cells implicates a subgroup of SNXs in selective and non-selective forms of autophagy. Using siRNA and CRISPR-Cas9,...

Descripción completa

Detalles Bibliográficos
Autores principales: Antón, Zuriñe, Betin, Virginie M. S., Simonetti, Boris, Traer, Colin J., Attar, Naomi, Cullen, Peter J., Lane, Jon D.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Company of Biologists Ltd 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7375690/
https://www.ncbi.nlm.nih.gov/pubmed/32513819
http://dx.doi.org/10.1242/jcs.246306
_version_ 1783561923139207168
author Antón, Zuriñe
Betin, Virginie M. S.
Simonetti, Boris
Traer, Colin J.
Attar, Naomi
Cullen, Peter J.
Lane, Jon D.
author_facet Antón, Zuriñe
Betin, Virginie M. S.
Simonetti, Boris
Traer, Colin J.
Attar, Naomi
Cullen, Peter J.
Lane, Jon D.
author_sort Antón, Zuriñe
collection PubMed
description The sorting nexins (SNXs) are a family of peripheral membrane proteins that direct protein trafficking decisions within the endocytic network. Emerging evidence in yeast and mammalian cells implicates a subgroup of SNXs in selective and non-selective forms of autophagy. Using siRNA and CRISPR-Cas9, we demonstrate that the SNX-BAR protein SNX4 is needed for efficient LC3 (also known as MAP1LC3) lipidation and autophagosome assembly in mammalian cells. SNX-BARs exist as homo- and hetero-dimers, and we show that SNX4 forms functional heterodimers with either SNX7 or SNX30 that associate with tubulovesicular endocytic membranes. Detailed image-based analysis during the early stages of autophagosome assembly reveals that SNX4–SNX7 is an autophagy-specific SNX-BAR heterodimer, required for efficient recruitment and/or retention of core autophagy regulators at the nascent isolation membrane. SNX4 partially colocalises with juxtanuclear ATG9A-positive membranes, with our data linking the autophagy defect upon SNX4 disruption to the mis-trafficking and/or retention of ATG9A in the Golgi region. Taken together, our findings show that the SNX4–SNX7 heterodimer coordinates ATG9A trafficking within the endocytic network to establish productive autophagosome assembly sites, thus extending knowledge of SNXs as positive regulators of autophagy.
format Online
Article
Text
id pubmed-7375690
institution National Center for Biotechnology Information
language English
publishDate 2020
publisher The Company of Biologists Ltd
record_format MEDLINE/PubMed
spelling pubmed-73756902020-08-05 A heterodimeric SNX4­–SNX7 SNX-BAR autophagy complex coordinates ATG9A trafficking for efficient autophagosome assembly Antón, Zuriñe Betin, Virginie M. S. Simonetti, Boris Traer, Colin J. Attar, Naomi Cullen, Peter J. Lane, Jon D. J Cell Sci Research Article The sorting nexins (SNXs) are a family of peripheral membrane proteins that direct protein trafficking decisions within the endocytic network. Emerging evidence in yeast and mammalian cells implicates a subgroup of SNXs in selective and non-selective forms of autophagy. Using siRNA and CRISPR-Cas9, we demonstrate that the SNX-BAR protein SNX4 is needed for efficient LC3 (also known as MAP1LC3) lipidation and autophagosome assembly in mammalian cells. SNX-BARs exist as homo- and hetero-dimers, and we show that SNX4 forms functional heterodimers with either SNX7 or SNX30 that associate with tubulovesicular endocytic membranes. Detailed image-based analysis during the early stages of autophagosome assembly reveals that SNX4–SNX7 is an autophagy-specific SNX-BAR heterodimer, required for efficient recruitment and/or retention of core autophagy regulators at the nascent isolation membrane. SNX4 partially colocalises with juxtanuclear ATG9A-positive membranes, with our data linking the autophagy defect upon SNX4 disruption to the mis-trafficking and/or retention of ATG9A in the Golgi region. Taken together, our findings show that the SNX4–SNX7 heterodimer coordinates ATG9A trafficking within the endocytic network to establish productive autophagosome assembly sites, thus extending knowledge of SNXs as positive regulators of autophagy. The Company of Biologists Ltd 2020-07-15 /pmc/articles/PMC7375690/ /pubmed/32513819 http://dx.doi.org/10.1242/jcs.246306 Text en © 2020. Published by The Company of Biologists Ltd http://creativecommons.org/licenses/by/4.0This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
spellingShingle Research Article
Antón, Zuriñe
Betin, Virginie M. S.
Simonetti, Boris
Traer, Colin J.
Attar, Naomi
Cullen, Peter J.
Lane, Jon D.
A heterodimeric SNX4­–SNX7 SNX-BAR autophagy complex coordinates ATG9A trafficking for efficient autophagosome assembly
title A heterodimeric SNX4­–SNX7 SNX-BAR autophagy complex coordinates ATG9A trafficking for efficient autophagosome assembly
title_full A heterodimeric SNX4­–SNX7 SNX-BAR autophagy complex coordinates ATG9A trafficking for efficient autophagosome assembly
title_fullStr A heterodimeric SNX4­–SNX7 SNX-BAR autophagy complex coordinates ATG9A trafficking for efficient autophagosome assembly
title_full_unstemmed A heterodimeric SNX4­–SNX7 SNX-BAR autophagy complex coordinates ATG9A trafficking for efficient autophagosome assembly
title_short A heterodimeric SNX4­–SNX7 SNX-BAR autophagy complex coordinates ATG9A trafficking for efficient autophagosome assembly
title_sort heterodimeric snx4­–snx7 snx-bar autophagy complex coordinates atg9a trafficking for efficient autophagosome assembly
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7375690/
https://www.ncbi.nlm.nih.gov/pubmed/32513819
http://dx.doi.org/10.1242/jcs.246306
work_keys_str_mv AT antonzurine aheterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT betinvirginiems aheterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT simonettiboris aheterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT traercolinj aheterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT attarnaomi aheterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT cullenpeterj aheterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT lanejond aheterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT antonzurine heterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT betinvirginiems heterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT simonettiboris heterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT traercolinj heterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT attarnaomi heterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT cullenpeterj heterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly
AT lanejond heterodimericsnx4snx7snxbarautophagycomplexcoordinatesatg9atraffickingforefficientautophagosomeassembly