Phototactic signaling network in rod-shaped cyanobacteria: A study on Synechococcus elongatus UTEX 3055.

Autor: Li SY; State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China., He C; State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, PR China., Valades-Cruz CA; State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, PR China., Zhang CC; State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, PR China; Hubei Hongshan Laboratory, Wuhan, Hubei 430070, PR China. Electronic address: cczhang@ihb.ac.cn., Yang Y; State Key Laboratory of Freshwater Ecology and Biotechnology, Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, PR China. Electronic address: yangyiling@ihb.ac.cn.
Jazyk: angličtina
Zdroj: Microbiological research [Microbiol Res] 2024 Nov 28; Vol. 292, pp. 127967. Date of Electronic Publication: 2024 Nov 28.
DOI: 10.1016/j.micres.2024.127967
Abstrakt: Light-controlled motility is advantageous for photosynthetic prokaryotes to better survive in environment with constantly changing light conditions. For cyanobacteria, light is both an energy source for photosynthesis and a stress factor. Consequently, some cyanobacteria evolved the ability to control type-IV pili (T4P)-mediated surface motility using a chemotaxis-like system in response to light signals. Extensive studies on the mechanism of phototaxis has been conducted in the spherical Synechocystis sp. PCC 6803 and the filamentous strain Nostoc punctiforme, while less is explored in rod-shaped cyanobacteria such as Synechococcus species. In this study, we investigated the phototaxis pathway in the unicellular rod-shaped cyanobacterium Synechococcus elongatus UTEX 3055, which exhibits bidirectional phototaxis using a single tax1 operon, in contrast to more complex and multiple gene clusters revealed in Synechocystis sp. PCC 6803. Results obtained by protein-protein interaction assays and protein subcellular localization experiments indicated that proteins encoded by the tax1 operon form large clusters that asymmetrically distributed both between the two poles and within the same pole. In vitro phosphorylation assays and site-directed mutations of conserved phosphorylation sites in PixL Se , PixG Se and PixH Se demonstrate that PixL Se acts as a histidine kinase, and PixG Se and PixH Se as response regulators for signal transduction. We further show that PixG Se and PixH Se are recruited to cell poles via interactions with the N-terminal region of PixL Se . While phosphotransfer reactions in this signaling pathway are critical for phototactic signaling, the two response regulators appear to play different roles in the control of phototaxis. This study provides a framework for further investigation into the complex phototactic signaling network in rod-shaped cyanobacteria with clearly defined cell poles in contrast to round shaped Synechocystis species with virtual cells poles through light-lensing effect.
Competing Interests: Declaration of Competing Interest None.
(Copyright © 2024 Elsevier GmbH. All rights reserved.)
Databáze: MEDLINE
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