Image-based genome-wide siRNA screen identifies selective autophagy factors.

Nature
Authors
Keywords
Abstract

Selective autophagy involves the recognition and targeting of specific cargo, such as damaged organelles, misfolded proteins, or invading pathogens for lysosomal destruction. Yeast genetic screens have identified proteins required for different forms of selective autophagy, including cytoplasm-to-vacuole targeting, pexophagy and mitophagy, and mammalian genetic screens have identified proteins required for autophagy regulation. However, there have been no systematic approaches to identify molecular determinants of selective autophagy in mammalian cells. Here, to identify mammalian genes required for selective autophagy, we performed a high-content, image-based, genome-wide small interfering RNA screen to detect genes required for the colocalization of Sindbis virus capsid protein with autophagolysosomes. We identified 141 candidate genes required for viral autophagy, which were enriched for cellular pathways related to messenger RNA processing, interferon signalling, vesicle trafficking, cytoskeletal motor function and metabolism. Ninety-six of these genes were also required for Parkin-mediated mitophagy, indicating that common molecular determinants may be involved in autophagic targeting of viral nucleocapsids and autophagic targeting of damaged mitochondria. Murine embryonic fibroblasts lacking one of these gene products, the C2-domain containing protein, SMURF1, are deficient in the autophagosomal targeting of Sindbis and herpes simplex viruses and in the clearance of damaged mitochondria. Moreover, SMURF1-deficient mice accumulate damaged mitochondria in the heart, brain and liver. Thus, our study identifies candidate determinants of selective autophagy, and defines SMURF1 as a newly recognized mediator of both viral autophagy and mitophagy.

Year of Publication
2011
Journal
Nature
Volume
480
Issue
7375
Pages
113-7
Date Published
2011 Dec 01
ISSN
1476-4687
URL
DOI
10.1038/nature10546
PubMed ID
22020285
PubMed Central ID
PMC3229641
Links
Grant list
AI062773 / AI / NIAID NIH HHS / United States
DK043351 / DK / NIDDK NIH HHS / United States
RC1 DK086502 / DK / NIDDK NIH HHS / United States
P30 DK040561 / DK / NIDDK NIH HHS / United States
AI109617 / AI / NIAID NIH HHS / United States
P30 DK043351 / DK / NIDDK NIH HHS / United States
R01 AI051367-06 / AI / NIAID NIH HHS / United States
P30 DK040561-15 / DK / NIDDK NIH HHS / United States
ZIA BC011168-03 / Intramural NIH HHS / United States
CA84254 / CA / NCI NIH HHS / United States
DK83756 / DK / NIDDK NIH HHS / United States
UL1 RR024982 / RR / NCRR NIH HHS / United States
Howard Hughes Medical Institute / United States
R01 AI062773 / AI / NIAID NIH HHS / United States
R01 AI051367 / AI / NIAID NIH HHS / United States
DK086502 / DK / NIDDK NIH HHS / United States
R01 DK083756 / DK / NIDDK NIH HHS / United States