Journal Article

Broadly conserved FlgV controls flagellar assembly and Borrelia burgdorferi dissemination in mice

Chang, Yuen-Yan, Jewett, Mollie W., Storz, Gisela, Lasseter, Amanda G., Soliman, Daniel, Aravind, L., Adams, Philip P., Zamba-Campero, Maxime, Yu, Huaxin, Silberman, Julia L., Liu, Jun

2024

Overview

Flagella propel pathogens through their environments, yet are expensive to synthesize and are immunogenic. Thus, complex hierarchical regulatory networks control flagellar gene expression. Spirochetes are highly motile bacteria, but peculiarly, the archetypal flagellar regulator σ 28 is absent in the Lyme spirochete Borrelia burgdorferi . Here, we show that gene bb0268 ( flgV ) in B. burgdorferi , previously and incorrectly annotated to encode the RNA-binding protein Hfq, is instead a structural flagellar component that modulates flagellar assembly. The flgV gene is broadly conserved in the flagellar superoperon alongside σ 28 in many Spirochaetae , Firmicutes and other phyla, with distant homologs in Epsilonproteobacteria . We find that B. burgdorferi FlgV is localized within flagellar basal bodies, and strains lacking flgV produce fewer and shorter flagellar filaments and are defective in cell division and motility. During the enzootic cycle, flgV -deficient B. burgdorferi survive and replicate in Ixodes ticks but are attenuated for infection and dissemination in mice. Our work defines infection timepoints when spirochete motility is most crucial and implicates FlgV as a broadly distributed structural flagellar component that modulates flagellar assembly. The control of flagellar synthesis and function in the Lyme spirochete Borrelia burgdorferi is poorly understood, as this pathogen lacks the typical flagellar sigma factor and transcriptional regulators. Here, the authors identify a broadly conserved structural flagellar component that modulates flagellar assembly and is important for cell division, motility and virulence.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 14/19 / 14/28 / 14/63 / 38/1 / 38/35 / 38/44 / 38/71 / 38/77 / 631/326/1320 / 631/326/41/2528 / 631/326/41/2531 / 631/326/421 / Animals / Assembly / Bacterial Proteins - genetics / Bacterial Proteins - metabolism / Basal bodies / Basal Bodies - metabolism / Borrelia burgdorferi / Borrelia burgdorferi - genetics / Borrelia burgdorferi - metabolism / Borrelia burgdorferi - pathogenicity / Borrelia burgdorferi - physiology / Cell division / Female / Filaments / Flagella / Flagella - genetics / Flagella - metabolism / Gene expression / Gene Expression Regulation, Bacterial / Humanities and Social Sciences / Immunogenicity / Ixodes - microbiology / Lyme Disease - microbiology / Mice / Motility / multidisciplinary / Pathogens / RNA-binding protein / Science / Science (multidisciplinary) / Sigma factor / Spirochetes / Ticks / Virulence