Author: Doron Teper
Internal reviewer:
Expert reviewer: WANTED!

Class: XopJ
Family: XopJ3
Prototype: AvrRxv (Xanthomonas euvesicatoria pv. euvesicatoria, ex Xanthomonas campestris pv. vesicatoria; strain 75-3)
GenBank ID: AAA27595.1 (373 aa)
RefSeq ID: WP_011346137.1 (373 aa)
3D structure: Unknown

AvrRxv/XopJ3 of X. euvesicatoria was identified to promote HR in non-host bean plants (Whalen et al. 1988).

Tn5 insertions in multiple hrp genes in XcvT 75-3 eliminated AvrRxv/XopJ3-mediated HR in tomato line Hawaii 7998 (Ciesiolka et al. 1998). Disruption of the type III secretion system in Xcv race T3 abolished secretion of AvrRxv into culture media (Bonshtien et al. 2004).

avrRxv is constitutively expressed in Xanthomonas tomato strain XcvT 92-14 (Ciesiolka et al. 1998). The expression of avrRxv was similar in NYB and XVM2 and was not dependent on hrpG or hrpX (Ciesiolka et al 1998). avrRxv has a perfect PIP-box starting at bp 465 with the sequence TTCGC-N15-TTCGC (Ciesiolka et al 1998).

AvrRxv induce hypersensitive response in tomato line Hawaii 7998 (Whalen et al. 1993)( Bonshtien et al. 2004), bean (Whalen et al. 1988) and Nicotiana benthamiana (Albers et al. 2019). Inactivation of arvRxv (avrRxv:: Ω ) in XcvT 75-3 eliminated HR induction and promoted growth in tomato line Hawaii 7998 (Whalen et al. 1993). Xcv race T3 (X. perforans) introduced with avrRxv induced resistance response in tomato line Hawaii 7998 which was characterized by HR, reduced bacterial growth in planta and significant alteration in host transcriptional profile (Bonshtien et al. 2004).

AvrRxv is localized predominantly to the cytoplasm and is possibly associated with the plasma and nuclear membranes (Bonshtien et al. 2004).

AvrRxv/XopJ3 belongs to the group of YopJ-family effectors. YopJ-family effectors share a conserved catalytic triad that is identical to that of the C55 family of cysteine proteases (Ma and Ma, 2016). Mutations in the AvrRxv protease catalytic core impaired elicitation of HR and inhibition of bacterial growth in tomato line Hawaii 7998 (Bonshtien et al. 2004).

AvrRxv interacts with tomato 14-3-3 protein (Whalen et al. 2008). Conservation

YES (X. euvesicatoria, X. hortorum , X. nasturtii, X. axonopodis)

YES (Pseudomonas syringae spp. (HopZ-family), Ralstonia solanacearum (PopP1), Acidovorax citrulli, Bradyrhizobium sp., Mesorhizobium sp., Sinorhizobium sp.)

Bonshtien A, Lev A, Gibly A, Debbie P, Avni A, Sessa G (2005). Molecular properties of the Xanthomonas AvrRxv effector and global transcriptional changes determined by its expression in resistant tomato plants. Mol. Plant Microbe Interact. 18: 300-310. DOI: 10.1094/MPMI-18-0300

Ciesiolka LD, Hwin T, Gearlds JD, Minsavage GV, Saenz R, Bravo M, Handley V, Conover SM, Zhang H, Caporgno J, Phengrasamy NB, Toms AO, Stall RE, Whalen MC (1999). Regulation of expression of avirulence gene avrRxv and identification of a family of host interaction factors by sequence analysis of avrBsT. Mol. Plant Microbe Interact. 12: 35-44. DOI: 10.1094/MPMI.1999.12.1.35

Whalen MC, Stall RE, Staskawicz BJ (1988). Characterization of a gene from a tomato pathogen determining hypersensitive resistance in non-host species and genetic analysis of this resistance in bean. Proc. Natl. Acad. Sci. USA 85: 6743-6747. DOI: 10.1073/pnas.85.18.6743

Whalen MC, Wang JF, Carland FM, Heiskell ME, Dahlbeck D, Minsavage GV, Jones JB, Scott JW, Stall RE, Staskawicz BJ (1993). Avirulence gene avrRxv from Xanthomonas campestris pv. vesicatoria specifies resistance on tomato line Hawaii 7998. Mol. Plant Microbe Interact. 6: 616-627. DOI: 10.1094/mpmi-6-616

Albers P, Üstün S, Witzel K, Kraner M, Börnke F (2019). A remorin from Nicotiana benthamiana interacts with the Pseudomonas type-III effector protein HopZ1a and is phosphorylated by the immune-related kinase PBS1. Mol. Plant Microbe Interact. 32:1229-1242. DOI: 10.1094/MPMI-04-19-0105-R

Ma KW, Ma W (2016). YopJ family effectors promote bacterial infection through a unique acetyltransferase activity. Microbiol. Mol. Biol. Rev. 80:1011-1027. DOI: 10.1128/MMBR.00032-16

Whalen M, Richter T, Zakhareyvich K, Yoshikawa M, Al-Azzeh D, Adefioye A, Spicer G, Mendoza LL, Morales CQ, Klassen V, Perez-Baron G, Toebe CS, Tzovolous A, Gerstman E, Evans E, Thompson C, Lopez M, Ronald PC (2008). Identification of a host 14-3-3 protein that Interacts with Xanthomonas effector AvrRxv. Physiol. Mol. Plant Pathol. 72: 46-55. DOI: 10.1016/j.pmpp.2008.05.006

This fact sheet is based upon work from COST Action CA16107 EuroXanth, supported by COST (European Cooperation in Science and Technology).