A plastid carbohydrate carrier mediates ribose recycling from nucleotide catabolism and glucose export from starch degradation.

ABSTRACT: In plants, nucleotide degradation releases ribose in the cytosol. An unidentified transporter then brings the ribose into the plastids for phosphorylation. This process of ribose recycling is particularly prominent in root nodules of soybean (Glycine max) and common bean (Phaseolus vulgaris) during symbiotic nitrogen fixation. In this biological context, we identified a plastid ribose transporter, which is an ortholog of the putative plastid glucose transporter (pGlcT) of Arabidopsis thaliana. We show that Arabidopsis mutants of At-pGlcT, but not of the related At-pGlcT2, accumulate ribose and fructose constitutively, whereas glucose accumulates only at night. Uridine feeding experiments leading to cytosolic ribose release indicated that At-pGlcT transports ribose from the cytosol into the

SUBMITTER: Voß L 

PROVIDER: S-EPMC12589546 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature