Reduction in Phosphoribulokinase Amount and Re-Routing Metabolism in Chlamydomonas reinhardtii CP12 Mutants - Archive ouverte HAL Access content directly
Journal Articles International Journal of Molecular Sciences Year : 2022

Reduction in Phosphoribulokinase Amount and Re-Routing Metabolism in Chlamydomonas reinhardtii CP12 Mutants

Abstract

The chloroplast protein CP12 is involved in the dark/light regulation of the Calvin–Benson–Bassham cycle, in particular, in the dark inhibition of two enzymes: glyceraldehyde−3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK), but other functions related to stress have been proposed. We knocked out the unique CP12 gene to prevent its expression in Chlamydomonas reinhardtii (ΔCP12). The growth rates of both wild-type and ΔCP12 cells were nearly identical, as was the GAPDH protein abundance and activity in both cell lines. On the contrary, the abundance of PRK and its specific activity were significantly reduced in ΔCP12, as revealed by relative quantitative proteomics. Isolated PRK lost irreversibly its activity over-time in vitro, which was prevented in the presence of recombinant CP12 in a redox-independent manner. We have identified amino acid residues in the CP12 protein that are required for this new function preserving PRK activity. Numerous proteins involved in redox homeostasis and stress responses were more abundant and the expressions of various metabolic pathways were also increased or decreased in the absence of CP12. These results highlight CP12 as a moonlighting protein with additional functions beyond its well-known regulatory role in carbon metabolism.
Fichier principal
Vignette du fichier
Cassy_Chlamy_deltaCP12_2022.pdf (2.37 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

hal-03594470 , version 1 (02-03-2022)

Licence

Attribution

Identifiers

Cite

Cassy Gérard, Régine Lebrun, Erwan Lemesle, Luisana Avilan, Kwang Chang, et al.. Reduction in Phosphoribulokinase Amount and Re-Routing Metabolism in Chlamydomonas reinhardtii CP12 Mutants. International Journal of Molecular Sciences, 2022, 23, ⟨10.3390/ijms23052710⟩. ⟨hal-03594470⟩

Collections

CNRS UNIV-AMU
31 View
28 Download

Altmetric

Share

Gmail Facebook X LinkedIn More