MARCH5-dependent NLRP3 ubiquitination is an essential step for NEK7 docking on the mitochondria

Park, Y.-J.; Dodantenna, N.; Kim, T.-H.; Lee, H.-S.; Yoo, Y.-S.; Lee, E.-S.; Lee, J.-H.; Kwon, M.-H.; Kang, H. C.; Lee, J.-S.; Cho, H.

doi:10.1101/2023.01.12.523764

bioRxiv · 10.1101/2023.01.12.523764

MARCH5-dependent NLRP3 ubiquitination is an essential step for NEK7 docking on the mitochondria

Park, Y.-J.·Dodantenna, N.·Kim, T.-H.·Lee, H.-S.·Yoo, Y.-S.·Lee, E.-S.·Lee, J.-H.·Kwon, M.-H.·Kang, H. C.·Lee, J.-S.·Cho, H.

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Abstract

The NLRP3 inflammasome is a global immune-sensor that is activated by a repertoire of endogenous and exogenous stimuli. NLRP3 translocates to mitochondria but whether mitochondria involvement in the inflammasome assembly is unclear. Here, we show that the mitochondrial E3 ligase MARCH5 is a key regulator of NLRP3 inflammasome assembly. Myeloid cell-specific March5 conditional knockout (March5 cKO) mice exhibited an attenuated mortality rate upon LPS or Pseudomonas aeruginosa challenge. Macrophages derived from March5 cKO mice failed to secrete IL-1{beta} and IL-18 after microbial infection. Mechanistically, MARCH5 interacts with the NACHT domain of NLRP3 and promotes K27-linked polyubiquitination of K324 and K430 residues of NLRP3. Ubiquitination-defective NLRP3 mutants neither bind to NEK7, nor form NLRP3 oligomers, but remain binding to MAVS. Accordingly, NLRP3 mutants led to abortive ASC speck formation and diminished IL-1{beta} production. We propose that MARCH5-dependent NLRP3 ubiquitination creates a docking site for NEK7 binding, playing as a fundamental step-wise regulator on the mitochondria.

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Park, Y.-J., Dodantenna, N., Kim, T.-H., Lee, H.-S., Yoo, Y.-S., Lee, E.-S., Lee, J.-H., Kwon, M.-H., Kang, H. C., Lee, J.-S., Cho, H.. 2023-01-12. MARCH5-dependent NLRP3 ubiquitination is an essential step for NEK7 docking on the mitochondria. https://doi.org/10.1101/2023.01.12.523764

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