The Photosystem II Repair Cycle Requires FtsH Turnover through the EngA GTPase

Oxygen and ROS in Photosynthesis

“…1 O 2 produced by Chl catabolites has been proposed to be involved in the hypersensitive response [431], and similarly to the flu-mutant [115], 1 O 2 produced by Chl catabolites has been suggested to initiate the EX1 pathway also in the wild type [432]. Interestingly, NADPH-protochlorophyllide oxidoreductases were shown to associate with EX1 and FtsH [425], though the interactions may be weak or transient, as they are not always observed [433]. PSII is a target of many pathogens [434] and a non-functional PSII repair cycle might also be involved in plant immunity [435].…”

Important roles of glycinebetaine in stabilizing the structure and function of the photosystem II complex under abiotic stresses

“…In addition, GB also protects some proteases (FtsH and DegP2, which are involved in the degradation of D1) from abiotic stresses, which has been shown to inhibit the interaction between these proteases and D1, or may directly inactivate these proteases ( Fig. 2c) (Kato et al 2018;Ohnishi and Murata 2006;Haußühl et al 2001). In this way, GB can promote the turnover of D1 and then facilitate the repair of PSII by protecting these proteases.…”

The default cyanobacterial linked genome: an interactive platform based on cyanobacterial linkage networks to assist functional genomics

“…EngA is an eubacterial GTPase with a unique structure in which two G domains are tandemly repeated [58] that plays essential roles in ribosome biogenesis in both bacteria and chloroplasts [59‐61]. It has been found membrane‐associated in Escherichia coli [62] and in Arabidopsis thaliana thylakoids, where it has been connected with the photosystem II repair cycle [63]. Chloroplast proteins (EngA1) are the closest homologs of Cyanobacterial EngA [64].…”