The proteome and phosphoproteome uncovers candidate proteins associated with vacuolar phosphate signal multipled by Vacuolar phosphate transporter1 (VPT1) in Arabidopsis

ABSTRACT: Plant vacuoles serve as the primary intracellular compartments for inorganic phosphate (Pi) storage. Passage of Pi across vacuolar membranes plays a critical role in buffering the cytoplasmic Pi level against fluctuations of external Pi and metabolic activities. To gain new insights into the proteins and processes vacuolar Pi level regulated by Vacuolar phosphate transporter1 (VPT1) in Arabidopsis, we carried out TMT labeling proteome and phosphoproteome profiling of Arabidopsis wild-type (WT) and vpt1 loss-of-function mutant plants. The vpt1 mutant had a reduced vacuolar Pi level, but an increased cytosol Pi level. The mutant was stunted as reflected in the reduction of the fresh weight compared with WT plants, and bolting earlier under normal growth conditions in soil. Over 5566 proteins and 7965 phosphopeptides were quantified. About 146 and 83 proteins were significantly changed at protein abundance or site-specific phosphorylation levels, but only 6 proteins were shared between them. Functional enrichment analysis revealed that Pi starvation signal in Arabidopsis vacuole is associated with photosynthesis, translation, RNA splicing, and defense response, consistent with similar studies in Arabidopsis. Except for PAP26, EIN2, and KIN10, which are reported to be associated with phosphate starvation signal, we also found many differential proteins involved in abscisic acid (ABA) signaling, such as CARK1, SnRK1, and AREB3, were changed in response to vacuolar Pi starvation. Our study illuminates several new aspects of the phosphate starvation response and identifies important targets for further investigation and potential crop improvement.

ORGANISM(S): Arabidopsis Thaliana

SUBMITTER: Yun Huang  

PROVIDER: PXD040698 | iProX | Wed Mar 08 00:00:00 GMT 2023

REPOSITORIES: iProX