Soybean NDR1‐like proteins bind pathogen effectors and regulate resistance signaling. Issue 2 (30th December 2013)

• Record Type: Journal Article
• Authors: Selote, Devarshi; Shine, M. B.; Robin, Guillaume P.; Kachroo, Aardra
• Is Part Of: New phytologist. Volume 202:Issue 2(2014)
• Page Start: 485
• Page End: 498
• Publication Date: 2013-12-30
• Subjects: Botany -- Periodicals; 580
• DOI: 10.1111/nph.12654
• Languages: English
• ISSNs: 0028-646X

Abstract

<abstract abstract-type="main" id="nph12654-abs-0001"> <title>Summary</title> <p> <list id="nph12654-list-0001" list-type="bullet"> <list-item> <p>Nonrace specific disease resistance 1 (NDR1) is a conserved downstream regulator of resistance (R) protein‐derived signaling. We identified two NDR1‐like sequences (GmNDR1a, b) from soybean, and investigated their roles in <italic>R‐</italic>mediated resistance and pathogen effector detection.</p> </list-item> <list-item> <p>Silencing <italic>GmNDR1a</italic> and <italic>b</italic> in soybean shows that these genes are required for resistance derived from the <italic>Rpg1‐b</italic>, <italic> Rpg3</italic>, and <italic>Rpg4</italic> loci, against <italic>Pseudomonas syringae</italic> (<italic>Psg</italic>) expressing <italic>avrB</italic>, <italic> avrB2</italic> and <italic>avrD1</italic>, respectively. Immunoprecipitation assays show that the GmNDR1 proteins interact with the AvrB2 and AvrD1 <italic>Psg</italic> effectors. This correlates with the enhanced virulence of <italic>Psg avrB2</italic> and <italic>Psg avrD1</italic> in GmNDR1‐silenced <italic>rpg3 rpg4</italic> plants, even though these strains are not normally more virulent on plants lacking cognate <italic>R</italic> loci.</p> </list-item> <list-item> <p>The GmNDR1 proteins interact with GmRIN4 proteins, but not with AvrB, or its cognate R protein Rpg1‐b. However, the GmNDR1 proteins promote AvrB‐independent activation of Rpg1‐b when coexpressed with a phosphomimic derivative of GmRIN4b.</p> </list-item> <list-item> <p>The role of GmNDR1 proteins in Rpg1‐b activation, their direct interactions with AvrB2/AvrD1, and a putative role in the virulence activities of Avr effectors, provides the first experimental evidence in support of the proposed role for NDR1 in transducing extracellular pathogen‐derived signals.</p> </list-item> </list> </p> </abstract>