V-ATPase and Osmotic Imbalances Activate Endolysosomal LC3 Lipidation

Overview

Journal Autophagy

Specialty Cell Biology

Date 2014 Dec 9

PMID 25484071

Citations 116

Authors

Oliver Florey

Noor Gammoh

Sung Eun Kim

Xuejun Jiang

Michael Overholtzer

Affiliations

Soon will be listed here.

Abstract

Recently a noncanonical activity of autophagy proteins has been discovered that targets lipidation of microtubule-associated protein 1 light chain 3 (LC3) onto macroendocytic vacuoles, including macropinosomes, phagosomes, and entotic vacuoles. While this pathway is distinct from canonical autophagy, the mechanism of how these nonautophagic membranes are targeted for LC3 lipidation remains unclear. Here we present evidence that this pathway requires activity of the vacuolar-type H(+)-ATPase (V-ATPase) and is induced by osmotic imbalances within endolysosomal compartments. LC3 lipidation by this mechanism is induced by treatment of cells with the lysosomotropic agent chloroquine, and through exposure to the Heliobacter pylori pore-forming toxin VacA. These data add novel mechanistic insights into the regulation of noncanonical LC3 lipidation and its associated processes, including LC3-associated phagocytosis (LAP), and demonstrate that the widely and therapeutically used drug chloroquine, which is conventionally used to inhibit autophagy flux, is an inducer of LC3 lipidation.

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References

Terebiznik M, Raju D, Vazquez C, Torbricki K, Kulkarni R, Blanke S . Effect of Helicobacter pylori's vacuolating cytotoxin on the autophagy pathway in gastric epithelial cells. Autophagy. 2009; 5(3):370-9. DOI: 10.4161/auto.5.3.7663. View

Segal A . The function of the NADPH oxidase of phagocytes and its relationship to other NOXs in plants, invertebrates, and mammals. Int J Biochem Cell Biol. 2007; 40(4):604-18. PMC: 2636181. DOI: 10.1016/j.biocel.2007.10.003. View

Sun-Wada G, Tabata H, Kawamura N, Aoyama M, Wada Y . Direct recruitment of H+-ATPase from lysosomes for phagosomal acidification. J Cell Sci. 2009; 122(Pt 14):2504-13. DOI: 10.1242/jcs.050443. View

Lamb F, Moreland J, Miller Jr F . Electrophysiology of reactive oxygen production in signaling endosomes. Antioxid Redox Signal. 2009; 11(6):1335-47. PMC: 2872256. DOI: 10.1089/ars.2008.2448. View

Thurston T, Ryzhakov G, Bloor S, von Muhlinen N, Randow F . The TBK1 adaptor and autophagy receptor NDP52 restricts the proliferation of ubiquitin-coated bacteria. Nat Immunol. 2009; 10(11):1215-21. DOI: 10.1038/ni.1800. View

Mizushima N, Yoshimori T, Levine B . Methods in mammalian autophagy research. Cell. 2010; 140(3):313-26. PMC: 2852113. DOI: 10.1016/j.cell.2010.01.028. View

Barth S, Glick D, Macleod K . Autophagy: assays and artifacts. J Pathol. 2010; 221(2):117-24. PMC: 2989884. DOI: 10.1002/path.2694. View

Behrends C, Sowa M, Gygi S, Harper J . Network organization of the human autophagy system. Nature. 2010; 466(7302):68-76. PMC: 2901998. DOI: 10.1038/nature09204. View

Berger S, Romero X, Ma C, Wang G, Faubion W, Liao G . SLAM is a microbial sensor that regulates bacterial phagosome functions in macrophages. Nat Immunol. 2010; 11(10):920-7. PMC: 3338319. DOI: 10.1038/ni.1931. View

10.

Schorn C, Frey B, Lauber K, Janko C, Strysio M, Keppeler H . Sodium overload and water influx activate the NALP3 inflammasome. J Biol Chem. 2010; 286(1):35-41. PMC: 3012992. DOI: 10.1074/jbc.M110.139048. View

11.

Amaravadi R, Lippincott-Schwartz J, Yin X, Weiss W, Takebe N, Timmer W . Principles and current strategies for targeting autophagy for cancer treatment. Clin Cancer Res. 2011; 17(4):654-66. PMC: 3075808. DOI: 10.1158/1078-0432.CCR-10-2634. View

12.

Weidberg H, Shpilka T, Shvets E, Abada A, Shimron F, Elazar Z . LC3 and GATE-16 N termini mediate membrane fusion processes required for autophagosome biogenesis. Dev Cell. 2011; 20(4):444-54. DOI: 10.1016/j.devcel.2011.02.006. View

13.

Johansen T, Lamark T . Selective autophagy mediated by autophagic adapter proteins. Autophagy. 2010; 7(3):279-96. PMC: 3060413. DOI: 10.4161/auto.7.3.14487. View

14.

Martinez J, Almendinger J, Oberst A, Ness R, Dillon C, Fitzgerald P . Microtubule-associated protein 1 light chain 3 alpha (LC3)-associated phagocytosis is required for the efficient clearance of dead cells. Proc Natl Acad Sci U S A. 2011; 108(42):17396-401. PMC: 3198353. DOI: 10.1073/pnas.1113421108. View

15.

Florey O, Kim S, Sandoval C, Haynes C, Overholtzer M . Autophagy machinery mediates macroendocytic processing and entotic cell death by targeting single membranes. Nat Cell Biol. 2011; 13(11):1335-43. PMC: 3223412. DOI: 10.1038/ncb2363. View

16.

Thurston T, Wandel M, von Muhlinen N, Foeglein A, Randow F . Galectin 8 targets damaged vesicles for autophagy to defend cells against bacterial invasion. Nature. 2012; 482(7385):414-8. PMC: 3343631. DOI: 10.1038/nature10744. View

17.

Marceau F, Bawolak M, Lodge R, Bouthillier J, Gagne-Henley A, Gaudreault R . Cation trapping by cellular acidic compartments: beyond the concept of lysosomotropic drugs. Toxicol Appl Pharmacol. 2011; 259(1):1-12. DOI: 10.1016/j.taap.2011.12.004. View

18.

Florey O, Overholtzer M . Autophagy proteins in macroendocytic engulfment. Trends Cell Biol. 2012; 22(7):374-80. PMC: 3383932. DOI: 10.1016/j.tcb.2012.04.005. View

19.

Klionsky D, Abdalla F, Abeliovich H, Abraham R, Acevedo-Arozena A, Adeli K . Guidelines for the use and interpretation of assays for monitoring autophagy. Autophagy. 2012; 8(4):445-544. PMC: 3404883. DOI: 10.4161/auto.19496. View

20.

Ma J, Becker C, Lowell C, Underhill D . Dectin-1-triggered recruitment of light chain 3 protein to phagosomes facilitates major histocompatibility complex class II presentation of fungal-derived antigens. J Biol Chem. 2012; 287(41):34149-56. PMC: 3464523. DOI: 10.1074/jbc.M112.382812. View