PIKfyve/Fab1 is required for efficient V-ATPase and hydrolase delivery to phagosomes, phagosomal killing, and restriction of Legionella infection

Buckley, C. M. et al. (2019) PIKfyve/Fab1 is required for efficient V-ATPase and hydrolase delivery to phagosomes, phagosomal killing, and restriction of Legionella infection. PLoS Pathogens, 15(2), e1007551. (doi: 10.1371/journal.ppat.1007551) (PMID:30730983) (PMCID:PMC6382210)

Abstract

By engulfing potentially harmful microbes, professional phagocytes are continually at risk from intracellular pathogens. To avoid becoming infected, the host must kill pathogens in the phagosome before they can escape or establish a survival niche. Here, we analyse the role of the phosphoinositide (PI) 5-kinase PIKfyve in phagosome maturation and killing, using the amoeba and model phagocyte Dictyostelium discoideum. PIKfyve plays important but poorly understood roles in vesicular trafficking by catalysing formation of the lipids phosphatidylinositol (3,5)-bisphosphate (PI(3,5)2) and phosphatidylinositol-5-phosphate (PI(5)P). Here we show that its activity is essential during early phagosome maturation in Dictyostelium. Disruption of PIKfyve inhibited delivery of both the vacuolar V-ATPase and proteases, dramatically reducing the ability of cells to acidify newly formed phagosomes and digest their contents. Consequently, PIKfyve- cells were unable to generate an effective antimicrobial environment and efficiently kill captured bacteria. Moreover, we demonstrate that cells lacking PIKfyve are more susceptible to infection by the intracellular pathogen Legionella pneumophila. We conclude that PIKfyve-catalysed phosphoinositide production plays a crucial and general role in ensuring early phagosomal maturation, protecting host cells from diverse pathogenic microbes.

• Item Type: Articles
• Additional Information: JSK is supported by a Royal Society University Research Fellowship UF140624. RHI is funded by Cancer Research UK Institute Group award A15672 and MRC grant G117/537. The Soldati laboratory is supported by multiple grants from the Swiss National Science Foundation (SNF) and TS is a member of iGE3 (http://www.ige3.unige.ch). HH is supported by the University of Zürich and the SNF (31003A_153200 and PZ00P3_161492). Microscopy studies were supported by a UK Medical Research Council grant (G0700091) and a Wellcome Trust grant (GR077544AIA).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Insall, Professor Robert

Creator Roles

Insall, R. H.: Conceptualization, Funding acquisition, Methodology, Resources, Supervision, Writing – review and editing

• Authors: Buckley, C. M., Heath, V. L., Guého, A., Bosmani, C., Knobloch, P., Sikakana, P., Personnic, N., Dove, S. K., Michell, R. H., Meier, R., Hilbi, H., Soldati, T., Insall, R. H., and King, J. S.
• College/School: College of Medical Veterinary and Life Sciences > School of Cancer Sciences
• Journal Name: PLoS Pathogens
• Publisher: Public Library of Science
• ISSN: 1553-7366
• ISSN (Online): 1553-7374
• Published Online: 07 February 2019
• Copyright Holders: Copyright © 2019 Buckley et al.
• First Published: First published in PLoS Pathogens 15(2): e1007551
• Publisher Policy: Reproduced under a Creative Commons License