Multiple Xanthomonas campestris pv. campestris 8004 type III effectors inhibit immunity induced by flg22
- PDF / 1,824,712 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 0 Downloads / 194 Views
REVIEW
Multiple Xanthomonas campestris pv. campestris 8004 type III effectors inhibit immunity induced by flg22 Yan Huang1 · Tongqi Li1 · Ting Xu1 · Zizhong Tang1 · Jingya Guo1 · Yi Cai1 Received: 17 December 2019 / Accepted: 30 September 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Main conclusion Xanthomonas campestris pv. campestris 8004 secretes several effector proteins that interfere with plant phosphorylation. Abstract Xanthomonas campestris pv. campestris (Xcc) can infect cruciferous plants and cause black rot. The strain Xcc8004 secretes effector proteins that interfere with plant cellular processes into host cells using a type III secretion (T3S) system. Several of the 24 predicted T3S effectors in the Xcc8004 genome have been implicated in the suppression of the Arabidopsis thaliana pattern-triggered immunity (PTI) response. We used an A. thaliana mesophyll protoplast-based assay to identify Xcc8004 T3S effectors that effectively interfere with PTI signalling induced by the bacterial peptide flg22. 11 of the 24 tested effector proteins (XopK, XopQ, HrpW, XopN, XopAC, XopD, XopZ1, XopAG, AvrBs2, XopL and XopX-1) inhibited expression of the flg22-inducible gene FRK1, and five effectors (XopK, XopG, XopQ, XopL and XopX-1) inhibited the expression of the flg22-inducible gene WRKY33. Therefore, there are 12 effector proteins that can inhibit the expression of relevant flg22-inducible genes. It was further investigated whether the 12 effector proteins affect the phosphorylation activation of mitogen-activated protein (MAP) kinases MPK3/MPK6, and four effector proteins (XopK, XopQ, XopZ1 and XopX-1) were found to markedly inhibit MPK3/MPK6 activation. Moreover, a subcellular localisation analysis revealed that the tested effectors were localised within various subcellular compartments. These results indicate that multiple T3S effectors in the Xcc8004 genome interfere with flg22-induced PTI signalling via various molecular mechanisms. Keywords Xcc8004 · Arabidopsis thaliana mesophyll protoplast · PTI · MAPK
Introduction Plants have evolved two types of defence systems to resist invading pathogens and survive in nature: pattern-triggered immunity (PTI) (Dodds and Rathjen 2010) and effectortriggered immunity (ETI) (Jones and Dangl 2006). Pathogen recognition receptors (PRRs) (Heilmann and Allenspach 2017) located on the exterior of the plasma membrane can detect bacterial pathogen-associated molecular patterns (PAMPs) (Macho and Zipfel 2014) such as bacterial flagellin and elongation factor thermo unstable (EF-Tu). Communicated by Anastasios Melis. * Yi Cai [email protected] 1
School of Life Sciences, Sichuan Agricultural University, Ya’an 625014, China
The flagellin-sensing 2 (FLS2) (Gómez-Gómez and Boller 2000) receptor is the most widely studied PRR. FLS2 is a receptor-like kinase (RLK) with a leucine-rich repeat (LRR) serine/threonine protein kinase domain that is involved in mitogen-activated protein kinase (MAPK) signalling related to innate immunity (Popescu et al.
Data Loading...
