biostudies-literatureArroyo-Perez EEDeutsche ForschungsgemeinschaftRP93004https://www.ebi.ac.uk/biostudies/studies/S-EPMC11620751biostudies-literatureUnknown13The coordination of cell cycle progression and flagellar synthesis is a complex process in motile bacteria. In γ-proteobacteria, the localization of the flagellum to the cell pole is mediated by the SRP-type GTPase FlhF. However, the mechanism of action of FlhF, and its relationship with the cell pole landmark protein HubP remain unclear. In this study, we discovered a novel protein called FipA that is required for normal FlhF activity and function in polar flagellar synthesis. We demonstrated that membrane-localized FipA interacts with FlhF and is required for normal flagellar synthesis in <i>Vibrio parahaemolyticus</i>, <i>Pseudomonas putida</i>, and <i>Shewanella putrefaciens</i>, and it does so independently of the polar localization mediated by HubP. FipA exhibits a dynamic localizatieLifeA conserved cell-pole determinant organizes proper polar flagellum formation.PMC11620751TRR 174-P12Hook JCArroyo-Perez EEWimmi SGlatter TRinggaard SAlvarado AThormann KfalseA conserved cell-pole determinant organizes proper polar flagellum formation.The coordination of cell cycle progression and flagellar synthesis is a complex process in motile bacteria. In γ-proteobacteria, the localization of the flagellum to the cell pole is mediated by the SRP-type GTPase FlhF. However, the mechanism of action of FlhF, and its relationship with the cell pole landmark protein HubP remain unclear. In this study, we discovered a novel protein called FipA that is required for normal FlhF activity and function in polar flagellar synthesis. We demonstrated that membrane-localized FipA interacts with FlhF and is required for normal flagellar synthesis in <i>Vibrio parahaemolyticus</i>, <i>Pseudomonas putida</i>, and <i>Shewanella putrefaciens</i>, and it does so independently of the polar localization mediated by HubP. FipA exhibits a dynamic localizati2024-01-01T00:00:00Z2024 Dec2026-06-02T10:48:44.777Z2025-04-03T23:52:00.641ZS-EPMC116207513963622310.7554/eLife.93004