Lack of Arabidopsis chloroplastic glucose-6-phosphate dehydrogenase 1 (G6PD1) affects lipid synthesis during cold stress response

• Published in: Plant science (Limerick) 2024-12, Vol.349, p.112260, Article 112260
• Main Authors: Landi, Simone, Vitale, Ermenegilda, Lanzilli, Mariamichela, Arena, Carmen, D'Ippolito, Giuliana, Fontana, Angelo, Esposito, Sergio
• Format: Article
• Language: English
• Subjects: Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis - physiology; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Chloroplast; Chloroplasts - metabolism; Cold Temperature; Cold-Shock Response; Desaturases; Fatty acid; Gene Expression Regulation, Plant; Glucosephosphate Dehydrogenase - genetics; Glucosephosphate Dehydrogenase - metabolism; Glycolipids; Lipid Metabolism; Lipids - biosynthesis; Pentose phosphate pathway; Phospholipids Photosynthesis; ROS
• ISSN: 0168-9452; 1873-2259; 1873-2259
• DOI: 10.1016/j.plantsci.2024.112260

Cold stress represents one of the major constraints for agricultural systems and crops productivity, inducing a wide range of negative effects. Particularly, long-term cold stress affects lipid metabolism, modifying the lipids/proteins ratio, the levels of phospholipids and glycolipids, and increasing lipids’ unsaturation in bio-membranes. Glucose-6-phosphate dehydrogenase (G6PDH) reported prominent roles as NADPH suppliers in response to oxidative perturbations. Cytosolic G6PDH was suggested as the main isoform involved in cold stress response, while a down-regulation of the chloroplastic P1-G6PDH was observed. We thus investigated an Arabidopsis mutant defective for the P1-G6PDH (KO-P1) using integrated approaches to verify a possible role of this isoform in low temperature tolerance. KO-P1 genotype showed an improved tolerance to cold stress, highlighting a better photosynthetic efficiency, a reduction in stress markers content and a different regulation of genes involved in stress response. Intriguingly, the lack of P1-G6PDH induced modification in the levels of the main fatty acid and lipid species affecting the morphology of chloroplasts and mitochondria, which was restored under cold. Globally, these results indicate a priming effect induced by the absence of P1-G6PDH able to improve the tolerance to abiotic stress. Our results suggest novel and specific abilities of P1-G6PDH, highlighting its central role in different aspects of plant physiology and metabolism. •In absence of P1-G6PDH, total G6PDH activity is compensated by other isoforms.•P1-G6PDH defective genotype shows an improved tolerance to cold stress.•Chloroplast metabolism and morphology are modified by the absence of P1-G6PDH.•P1-G6PDH showed an important role in the biosynthesis of fatty acid and lipids.