Dataset Information

Distinct branches of the N-end rule pathway modulate the plant immune response

ABSTRACT: The N-end rule pathway is a highly conserved constituent of the ubiquitin proteasome system, though little information exists regarding biological roles. Here we show that the cysteine (Cys-) and glutamine (Gln)-specific amino-terminal (Nt)-amidase NTAQ1 branches are both components of the plant immune system, through the E3 ligase PROTEOLYSIS (PRT)6. Both ntaq1 and prt6 mutants of Arabidopsis thaliana showed enhanced basal resistance to the hemibiotroph pathogen Pseudomonas syringae, associated with constitutive expression of defence-response genes and activation of synthesis pathway of the phytoalexin camalexin. We observed a role in stomatal defence for the Nt-Cys substrates ETHYLENE RESPONSE FACTOR VII transcription factors. Transgenic barley lines with reduced HvPRT6 expression showed enhanced resistance against Ps japonica and Blumeria graminis f. sp. Hordei, indicating a conserved role of the pathway in immunity. These data demonstrate that different branches of the N-end rule pathway act at distinct levels of the plant immune response.

INSTRUMENT(S): Q Exactive HF

ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)

TISSUE(S): Plant Cell, Leaf

SUBMITTER: Jarne Pauwels

LAB HEAD: Michael J. Holdsworth

PROVIDER: PXD008520 | Pride | 2018-11-06

REPOSITORIES: Pride

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			Action	DRS
	H02084_6230_EXT-484_HoldsworthLab_Col0_Ctrl_1.raw	Raw
	H02086_6230_EXT-484_HoldsworthLab_ntaq1-3_Ctrl_1.raw	Raw
	H02088_6230_EXT-484_HoldsworthLab_Col0_Ctrl_2.raw	Raw
	H02090_6230_EXT-484_HoldsworthLab_ntaq1-3_Ctrl_2.raw	Raw
	H02092_6230_EXT-484_HoldsworthLab_Col0_Ctrl_3.raw	Raw

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Distinct branches of the N-end rule pathway modulate the plant immune response.

Vicente Jorge J Mendiondo Guillermina M GM Pauwels Jarne J Pastor Victoria V Izquierdo Yovanny Y Naumann Christin C Movahedi Mahsa M Rooney Daniel D Gibbs Daniel J DJ Smart Katherine K Bachmair Andreas A Gray Julie E JE Dissmeyer Nico N Castresana Carmen C Ray Rumiana V RV Gevaert Kris K Holdsworth Michael J MJ

The New phytologist 20180817 2

The N-end rule pathway is a highly conserved constituent of the ubiquitin proteasome system, yet little is known about its biological roles. Here we explored the role of the N-end rule pathway in the plant immune response. We investigated the genetic influences of components of the pathway and known protein substrates on physiological, biochemical and metabolic responses to pathogen infection. We show that the glutamine (Gln) deamidation and cysteine (Cys) oxidation branches are both components ...[more]

PMID: 30117535

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