Subcellular localization and developmental regulation of cytosolic, soluble pyrophosphatase isoforms in Arabidopsis thaliana

Authors : Zahide Neslihan ÖZTÜRK, Steffen GREINER, Thomas RAUSCH

Pages : 1036-1049

Doi:10.3906/bot-1403-67

View : 15 | Download : 9

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Pyrophosphate insert ignore into journalissuearticles values(PPI); is the by-product of several reversible key reactions of primary metabolism. Thus, generated PPi should be removed by hydrolysis via pyrophosphatases to prevent accumulation and to drive anabolism. In plastids, a plastidic, soluble pyrophosphatase splits PPi released by ADPG pyrophosphorylase. The cytosolic PPi pool is believed to be hydrolyzed by tonoplast- and/or Golgi-integral H+-translocating pyrophosphatases. The Arabidopsis thaliana insert ignore into journalissuearticles values(L.); Heynh. genome encodes 6 soluble pyrophosphatase isoforms insert ignore into journalissuearticles values(PPas);, 1 of which was shown to be localized in plastids. The remaining 5 of those PPas insert ignore into journalissuearticles values(PPas 1-5); are more similar to each other with highly conserved protein sequences. They all lack known targeting sequences and are thought to reside in the cytosol. To address their role and redundancy in plants, we performed insert ignore into journalissuearticles values(i); subcellular targeting of C-terminal PPa:EGFP fusions, insert ignore into journalissuearticles values(ii); analysis of transgenic promoter Beta-glucuronidase insert ignore into journalissuearticles values(GUS); lines to depict differential expression during plant development, and insert ignore into journalissuearticles values(iii); transcript quantification via real-time PCR to corroborate promoter-GUS data. The results revealed pronounced tissue specificity and developmental regulation for each PPa isoform, but also partial redundancy with coexpression of several PPa isoforms in all plant tissues.
Keywords : Brassicaceae, Cruciferae, soluble pyrophosphatase family, in silico subcellular localization, EGFP chimeras, histochemical GUS staining, real time PCR