RRC ID 7181
Author Ariizumi T, Higuchi K, Arakaki S, Sano T, Asamizu E, Ezura H.
Title Genetic suppression analysis in novel vacuolar processing enzymes reveals their roles in controlling sugar accumulation in tomato fruits.
Journal J Exp Bot
Abstract In plant cells, many vacuolar proteins are synthesized as precursors in the endoplasmic reticulum and are subsequently transported to the vacuole. These precursors are subject to post-translational modifications to allow the active mature forms to be produced. Vacuolar processing enzyme (VPE) has been identified as a family of cysteine proteases involved in protein maturation in the vacuole. In this study, novel VPE genes were isolated from tomato (Solanum lycopersicum), and they were designated SlVPE1-SlVPE5. Phylogenic analysis suggested that SlVPE1 and SlVPE2 were categorized as the seed coat type, SlVPE4 was categorized as the seed type, and both SlVPE3 and SlVPE5 were categorized as the vegetative type. Expression analysis demonstrated that these genes were expressed during fruit development, and that their expression profiles agreed with this classification. High VPE enzyme activity was observed during tomato fruit development; the enzyme activity was correlated with the SlVPE mRNA levels, indicating that the SlVPE encoded active VPE proteins. The total sugar content was higher in RNA interference (RNAi) lines compared with the control plants, suggesting negative roles for SlVPE in sugar accumulation. The quantitative expression analysis of each SlVPE gene in the RNAi lines suggested that the suppression of SlVPE5 probably had the strongest effect on the sugar accumulation observed. The suppression of SlVPE did not influence the total amino acid content, suggesting that the molecular targets of SlVPE were mainly involved in sugar accumulation.
Volume 62(8)
Pages 2773-86
Published 2011-5-1
DOI 10.1093/jxb/erq451
PII erq451
PMID 21282322
MeSH Amino Acids / metabolism Carbohydrate Metabolism / genetics* Cysteine Endopeptidases / genetics* Cysteine Endopeptidases / metabolism Fruit / enzymology* Fruit / genetics* Fruit / growth & development Gene Expression Regulation, Enzymologic Gene Expression Regulation, Plant Genes, Reporter Glucuronidase / metabolism Immunohistochemistry Lycopersicon esculentum / enzymology* Lycopersicon esculentum / genetics* Lycopersicon esculentum / growth & development Phylogeny Plant Proteins / genetics Plant Proteins / metabolism Plants, Genetically Modified RNA Interference RNA, Messenger / genetics RNA, Messenger / metabolism Reverse Transcriptase Polymerase Chain Reaction Suppression, Genetic* Time Factors
IF 5.908
Times Cited 28
Tomato TOMJPF00001