title: Post-transcriptional regulation of fruit ripening and disease resistance in tomato by the vacuolar protease SlVPE3.
abstract: Proteases represent one of the most abundant classes of enzymes in eukaryotes and are known to play key roles in many biological processes in plants. However, little is known about their functions in fruit ripening and disease resistance, which are unique to flowering plants and required for seed maturation and dispersal. Elucidating the genetic mechanisms of fruit ripening and disease resistance is an important goal given the biological and dietary significance of fruit.
  
  
  
  Through expression profile analyses of genes encoding tomato (Solanum lycopersicum) cysteine proteases, we identify a number of genes whose expression increases during fruit ripening. RNA interference (RNAi)-mediated repression of SlVPE3, a vacuolar protease gene, results in alterations in fruit pigmentation, lycopene biosynthesis, and ethylene production, suggesting that SlVPE3 is necessary for normal fruit ripening. Surprisingly, the SlVPE3 RNAi fruit are more susceptible to the necrotrophic pathogen Botrytis cinerea. Quantitative proteomic analysis identified 314 proteins that differentially accumulate upon SlVPE3 silencing, including proteins associated with fruit ripening and disease resistance. To identify the direct SlVPE3 targets and mechanisms contributing to fungal pathogen resistance, we perform a screening of SlVPE3-interacting proteins using co-immunoprecipitation coupled with mass spectrometry. We show that SlVPE3 is required for the cleavage of the serine protease inhibitor KTI4, which contributes to resistance against the fungal pathogen B. cinerea.
  
  
  
  Our findings contribute to elucidating gene regulatory networks and mechanisms that control fruit ripening and disease resistance responses.
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Haidian District, Beijing, 100093, China.
authors.forename: Weihao
authors.initials: W
authors.lastname: Wang
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Haidian District, Beijing, 100093, China.|University of Chinese Academy of Sciences, Yuquanlu, Beijing, 100049, China.
authors.forename: Jianghua
authors.initials: J
authors.lastname: Cai
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Haidian District, Beijing, 100093, China.|University of Chinese Academy of Sciences, Yuquanlu, Beijing, 100049, China.
authors.forename: Peiwen
authors.initials: P
authors.lastname: Wang
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Haidian District, Beijing, 100093, China.|University of Chinese Academy of Sciences, Yuquanlu, Beijing, 100049, China.
authors.forename: Shiping
authors.initials: S
authors.lastname: Tian
authors.affiliation: Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, No. 20 Nanxincun, Xiangshan, Haidian District, Beijing, 100093, China. gzqin@ibcas.ac.cn.
authors.forename: Guozheng
authors.identifier: 0000-0003-3046-1177
authors.initials: G
authors.lastname: Qin
mesh_terms: D002352:Carrier Proteins; D016000:Cluster Analysis; D060467:Disease Resistance / Q000235:genetics; D005638:Fruit / Q000235:genetics* / Q000254:growth & development; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D056726:Genetic Association Studies; D054884:Host-Pathogen Interactions / Q000235:genetics; D018551:Solanum lycopersicum / Q000235:genetics* / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000235:genetics* / Q000378:metabolism*; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics; D011485:Protein Binding; D025941:Protein Interaction Mapping; D059748:Proteolysis; D020543:Proteome; D040901:Proteomics / Q000379:methods; D012323:RNA Processing, Post-Transcriptional; D014617:Vacuoles / Q000201:enzymology*
chemical_list: D002352:Carrier Proteins; D020543:Proteome; D010447:Peptide Hydrolases
keywords: Disease resistance; Fruit ripening; Protease; Protease inhibitor; Quantitative proteome; RNA interference; Tomato; Vacuolar processing enzyme