Abstract
Host restriction factors mediate intrinsic immunity against infections, thus serving as promising targets for host-directed therapy (HDT) against drug-resistant pathogens. While restriction factors counteracting viruses have been extensively studied, those targeting bacteria, particularly those with broad-spectrum activity, remain largely unexplored. Here, through screening for host factors promoting lysosomal acidification, a crucial process clearing pathogens, we identify the host small GTPase Rab14 as a restriction factor with broad-spectrum activity against multiple bacteria and viruses. Mechanistically, upon pathogen infections, GTP-bound Rab14 increases and binds to the calcium/calmodulin-dependent protein kinase type 2 delta (CAMK2D), suppressing CAMK2D-mediated phosphorylation of V0a1, the critical subunit determining V-ATPase localization, thus promoting V0a1 binding to the COPⅡ complex to facilitate V-ATPase trafficking from the endoplasmic reticulum to lysosomes, resulting in lysosomal acidification and pathogen clearance. Taken together, our data demonstrate an unrecognized intrinsic immune mechanism mediated by Rab14-CAMK2D-V-ATPase axis, which might be a promising target for infectious diseases.
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All data are available in the main text and the Supplementary Materials. The plasmids and cell lines generated in this study are available from the corresponding author. Source data are provided with this paper.
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Acknowledgements
This work was supported by the National Natural Science Foundation of China (32530001 and 82330069 to C.H.L., 82372653 and 82572578 to J.W.), the Shenzhen Medical Research Funding (B2302035 to C.H.L.), the Prevention and Control of Emerging and Major Infectious Diseases—National Science and Technology Major Project (2025ZD01903800 to C.H.L. and 2025ZD01907200 to J.W.), the National Key Research and Development Program of China (2022YFC2302900 to C.H.L. and J.W., and 2021YFA1300200 to L.Z. and C.H.L.), the Major Project of Guangzhou National Laboratory (GZNL2024A01023 to C.H.L.), the State Key Laboratory of Proteomics (SKLP-X202401 to C.H.L. and L.Z.), and the CAS Project for Young Scientists in Basic Research (YSBR-010 to J.W.). We thank T. Zhao (Institute of Microbiology, Chinese Academy of Sciences, Beijing) for helping with flow cytometry, X. Zhang (Institute of Microbiology, Chinese Academy of Sciences, Beijing) for helping with confocal microscopic analysis, and J. Hao (Core Facility for Protein Research, Institute of Biophysics, Chinese Academy of Sciences, Beijing) for helping with histological analysis.
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C.H.L. conceived the study and carried out the project administration. C.H.L., J.W., L.Z., and B.L. managed funding acquisition. Z.Lei., L.Q., and J.W. performed the experiments and functional analyses. P.G., Y.Q., T.S., Q.C., Y.Wang., S.L., C.Q., M.Z., Z.Z., Y.Wu., X.Z., Y.Z., and B.L. assisted with experiments. Z.Lu. performed the bioinformatic analyses. C.H.L., J.W., L.Z., Z.Lei., and L.Q. wrote and revised the manuscript. All authors read and approved the final version of the manuscript.
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Lei, Z., Qiang, L., Ge, P. et al. Rab14 restricts pathogens by promoting V-ATPase lysosomal delivery to drive lysosomal acidification. Nat Commun (2026). https://doi.org/10.1038/s41467-026-70258-w
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DOI: https://doi.org/10.1038/s41467-026-70258-w
