This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
bacteria:t3e:xopj2 [2020/07/08 17:26] rkoebnik [Biological function] |
— (current) | ||
---|---|---|---|
Line 1: | Line 1: | ||
- | ====== XopJ2 ====== | ||
- | |||
- | Author: [[https:// | ||
- | Internal reviewer: FIXME \\ | ||
- | Expert reviewer: FIXME | ||
- | |||
- | Class: XopJ2 (//syn.// AvrBsT) Family: XopJ2 Prototype: AvrBsT (// | ||
- | RefSeq ID: [[https:// | ||
- | 3D structure: not available | ||
- | |||
- | ===== Biological function ===== | ||
- | |||
- | === How discovered? === | ||
- | |||
- | The //avrBsT// avirulence gene was first identified in the XcvT race 1 strain 75-3, which is avirulent on the pepper cultivar ECW (Minsavage //et al//., 1990). The //avrBsT// gene was localized on an indigenous plasmid of approximately 41 kb in the XcvT race 1 strain 75-3 (Minsavage //et al//., 1990). Spontaneous loss of the plasmid-borne //avrBsT// allowed XcvT race 1 75-3 mutants to cause disease on normally resistant pepper lines, suggesting simple genetic control of nonhost, // | ||
- | === (Experimental) evidence for being a T3E === | ||
- | |||
- | C-myc epitope-tagged AvrBsT protein was detected in culture supernatants of the //Xcv// strain 85* only in the presence of a functional type III apparatus and not in a //hrcV// mutant, showing that the protein is secreted in an hrp-dependent manner (Escolar //et al//., 2001). Transient expression of //avrBsT// in resistant host plants using // | ||
- | === Regulation === | ||
- | |||
- | Expression of the //avrBsT// gene is constitutive and independent of the //hrp// gene regulators in //Xcv// strain 85-10, //hrpG// and //hrpX// (Escolar //et al//., 2001). | ||
- | === Phenotypes === | ||
- | |||
- | * AvrBsT was found to suppress the hypersensitive response (HR) that is elicited by the effector protein AvrBs1 from // | ||
- | * AvrBsT was found to act as a virulence factor in tomato plants (Kim //et al//., 2010). | ||
- | * Growth of // | ||
- | * AvrBsT also significantly compromised callose deposition and defense-marker gene expression in tomato plants when inoculating // | ||
- | * One out of 71 // | ||
- | * Resistance in Pi-0 was found to be caused by a recessive mutation predicted to inactivate a carboxylesterase known to hydrolyze lysophospholipids and acylated proteins in eukaryotes. Transgenic Pi-0 plants expressing the wild-type allele from the //A. thaliana// | ||
- | * It was later shown that Pi-0 leaves infected with // | ||
- | * Transgenic // | ||
- | * Phylogenomics revealed that a host-range expansion of //X. euvesicatoria// | ||
- | * Later, AvrBsT was found to contribute to fitness of // | ||
- | |||
- | === Localization === | ||
- | |||
- | Transient coexpression of // | ||
- | |||
- | === Enzymatic function === | ||
- | |||
- | AvrBsT belongs to the YopJ family, members of which were shown to act as cysteine proteases, which contain a catalytic triad (His, Glu, Cys). It was shown that AvrBsT requires a functional protease catalytic core to trigger defense responses in resistant plant cells, suggesting that AvrBsT acts as a protease to disrupt immune signaling pathways (Orth //et al//., 2000). AvrBsT was later shown to possess acetyltransferase activity and acetylates ACIP1 (for // | ||
- | |||
- | === Interaction partners === | ||
- | |||
- | * Yeast two-hybrid based analyses identified a putative regulator of sugar metabolism, SNF1-related kinase 1 (SnRK1), as an interactor of AvrBsT (Szczesny //et al//., 2010). Gene silencing experiments revealed that SnRK1 is required for the induction of the AvrBs1-specific HR, which is suppressed by AvrBsT (Szczesny //et al//., 2010). Thus, SnRK1 may be involved in the AvrBsT-mediated suppression of the AvrBs1-specific HR (Szczesny //et al//., 2010). | ||
- | * Later, the pepper SGT1 (for suppressor of the G2 allele of //skp1//) and PIK1 (for receptor-like cytoplasmic kinase1) were identified as a host interactor of AvrBsT. SGT1 forms a heterotrimeric complex with both AvrBsT and PIK1 exclusively in the cytoplasm. PIK1 specifically phosphorylates SGT1 and AvrBsT in vitro. AvrBsT binding to SGT1 resulted in the inhibition of PIK1-mediated SGT1 phosphorylation and subsequent nuclear transport of the SGT1-PIK1 complex (Kim //et al//., 2014). | ||
- | * Using a yeast two-hybrid screen, the pepper CaHSP70a was identified as another AvrBsT-interacting protein. Bimolecular fluorescence complementation and co-immunoprecipitation assays confirmed the specific interaction between CaHSP70a and AvrBsT //in planta// | ||
- | * Using a yeast two-hybrid screen, the pepper aldehyde dehydrogenase 1 (CaALDH1) was identified as another AvrBsT-interacting protein. Bimolecular fluorescence complementation and co-immunoprecipitation assays confirmed the interaction between CaALDH1 and AvrBsT //in planta// | ||
- | |||
- | ===== Conservation ===== | ||
- | |||
- | === In xanthomonads === | ||
- | |||
- | Yes (//X. euvesicatoria//, | ||
- | |||
- | === In other plant pathogens/ | ||
- | |||
- | Yes (// | ||
- | |||
- | ===== References ===== | ||
- | |||
- | Abrahamian P, Timilsina S, Minsavage GV, Kc S, Goss EM, Jones JB, Vallad GE (2018). The type III effector AvrBsT enhances // | ||
- | |||
- | Cheong MS, Kirik A, Kim JG, Frame K, Kirik V, Mudgett MB (2014). AvrBsT acetylates // | ||
- | |||
- | Ciesiolka LD, Hwin T, Gearlds JD, Minsavage GV, Saenz R, Bravo M, Handley V, Conover SM, ZhangH, Caporgno J, Phengrasamy NB, Toms AO, Stall RE, Whalen MC (1999). Regulation of expression of avirulence gene // | ||
- | |||
- | Cunnac S, Wilson A, Nuwer J, Kirik A, Baranage G, Mudgett MB (2007). A conserved carboxylesterase is a suppressor of AvrBsT-elicited resistance in // | ||
- | |||
- | Escolar L, Van Den Ackerveken G, Pieplow S, Rossier O, Bonas U (2001). Type III secretion and //in planta// | ||
- | |||
- | Hwang IS, Kim NH, Choi DS, Hwang BK (2012). Overexpression of // | ||
- | |||
- | Kim NH, Choi HW, Hwang BK (2010). // | ||
- | |||
- | Kim NH, Hwang BK (2015a). Pepper heat shock protein 70a interacts with the type III effector AvrBsT and triggers plant cell death and immunity. Plant Physiol. 167: 307-322. DOI: [[https:// | ||
- | |||
- | Kim NH, Hwang BK (2015b). Pepper aldehyde dehydrogenase CaALDH1 interacts with // | ||
- | |||
- | Kim NH, Kim DS, Chung EH, Hwang BK (2014). Pepper suppressor of the G2 allele of // | ||
- | |||
- | Kim NH, Kim BS, Hwang BK (2013). Pepper arginine decarboxylase is required for polyamine and γ-aminobutyric acid signaling in cell death and defense response. Plant Physiol. 162: 2067-2083. DOI: [[https:// | ||
- | |||
- | Kirik A, Mudgett MB (2009) SOBER1 phospholipase activity suppresses phosphatidic acid accumulation and plant immunity in response to bacterial effector AvrBsT. Proc. Natl. Acad. Sci. U.S.A. 106: 20532-20537. DOI: [[https:// | ||
- | |||
- | Minsavage GV, Dahlbeck D, Whalen MC, Kearny B, Bonas U, Staskawicz BJ, Stall RE (1990). Gene-for-gene relationships specifying disease resistance in // | ||
- | |||
- | Orth K, Xu ZH, Mudgett MB, Bao ZQ, Palmer LE, Bliska JB, Mangel WF, Staskawicz B, Dixon JE (2000). Disruption of signaling by // | ||
- | |||
- | Prochaska H, Thieme S, Daum S, Grau J, Schmidtke C, Hallensleben M, John P, Bacia K, Bonas U (2018). A conserved motif promotes HpaB-regulated export of type III effectors from // | ||
- | |||
- | Schwartz AR, Potnis N, Timilsina S, Wilson M, Patané J, Martins J Jr, Minsavage GV, Dahlbeck D, Akhunova A, Almeida N, Vallad GE, Barak JD, White FF, Miller SA, Ritchie D, Goss E, Bart RS, Setubal JC, Jones JB, Staskawicz BJ (2015). Phylogenomics of // | ||
- | |||
- | Szczesny R, Büttner D, Escolar L, Schulze S, Seiferth A, Bonas U (2010). Suppression of the AvrBs1-specific hypersensitive response by the YopJ effector homolog AvrBsT from // | ||