NPR1 has been found to be a key transcriptional regulator in some plant defence responses. There are nine We used bioinformatics and reverse genetics approaches to study the expression and function of each We found six members of We discovered a new mode of NPR1 action in wheat at the
Stem rust is an important disease of wheat that can be controlled using resistance genes. The gene
- PAR ID:
- 10153551
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
more » « less
Summary NPR1 homologues (TaNPR1 ) in wheat, but little research has been done to understand the function of thoseNPR1 ‐like genes in the wheat defence response against stem rust (Puccinia graminis f. sp.tritici ) pathogens.TaNPR1 .TaNPR1 located on homoeologous group 3 chromosomes (designated asTaG3NPR1 ) and three on homoeologous group 7 chromosomes (designated asTaG7NPR1 ). The group 3 NPR1 proteins regulate transcription of SA‐responsivePR genes. Downregulation of all theTaNPR1 homologues via virus‐induced gene co‐silencing resulted in enhanced resistance to stem rust. More specifically downregulatingTaG7NPR1 homeologues orTa7ANPR1 expression resulted in stem rust resistance phenotype. By contrast, knocking downTaG3NPR1 alone did not show visible phenotypic changes in response to the rust pathogen. Knocking outTa7ANPR1 enhanced resistance to stem rust. TheTa7ANPR1 locus is alternatively spliced under pathogen inoculated conditions.Ta7ANPR1 locus through an NB‐ARC–NPR1 fusion protein negatively regulating the defence to stem rust infection. -
more » « less
Abstract The wheat wild relative
Aegilops tauschii was previously used to transfer theLr42 leaf rust resistance gene into bread wheat.Lr42 confers resistance at both seedling and adult stages, and it is broadly effective against all leaf rust races tested to date.Lr42 has been used extensively in the CIMMYT international wheat breeding program with resulting cultivars deployed in several countries. Here, using a bulked segregant RNA-Seq (BSR-Seq) mapping strategy, we identify three candidate genes forLr42 . Overexpression of a nucleotide-binding site leucine-rich repeat (NLR) gene AET1Gv20040300 induces strong resistance to leaf rust in wheat and a mutation of the gene disrupted the resistance. TheLr42 resistance allele is rare inAe. tauschii and likely arose from ectopic recombination. Cloning ofLr42 provides diagnostic markers and over 1000 CIMMYT wheat lines carryingLr42 have been developed documenting its widespread use and impact in crop improvement. -
null (Ed.)Plant subtilases (SBTs) or subtilisin-like proteases comprise a very diverse family of serine peptidases that participates in a broad spectrum of biological functions. Despite increasing evidence for roles of SBTs in plant immunity in recent years, little is known about wheat (Triticum aestivum) SBTs (TaSBTs). Here, we identified 255 TaSBT genes from bread wheat using the latest version 2.0 of the reference genome sequence. The SBT family can be grouped into five clades, from TaSBT1 to TaSBT5, based on a phylogenetic tree constructed with deduced protein sequences. In silico protein-domain analysis revealed the existence of considerable sequence diversification of the TaSBT family which, together with the local clustered gene distribution, suggests that TaSBT genes have undergone extensive functional diversification. Among those TaSBT genes whose expression was altered by biotic factors, TaSBT1.7 was found to be induced in wheat leaves by chitin and flg22 elicitors, as well as six examined pathogens, implying a role for TaSBT1.7 in plant defense. Transient overexpression of TaSBT1.7 in Nicotiana benthamiana leaves resulted in necrotic cell death. Moreover, knocking down TaSBT1.7 in wheat using barley stripe mosaic virus-induced gene silencing compromised the hypersensitive response and resistance against Puccinia striiformis f. sp. tritici, the causal agent of wheat stripe rust. Taken together, this study defined the full complement of wheat SBT genes and provided evidence for a positive role of one particular member, TaSBT1.7, in the incompatible interaction between wheat and a stripe rust pathogen.more » « less
-
null (Ed.)Abstract Key message The first cytological characterization of the 2N v S segment in hexaploid wheat; complete de novo assembly and annotation of 2N v S segment; 2N v S frequency is increasing 2N v S and is associated with higher yield. Abstract The Aegilops ventricosa 2N v S translocation segment has been utilized in breeding disease-resistant wheat crops since the early 1990s. This segment is known to possess several important resistance genes against multiple wheat diseases including root knot nematode, stripe rust, leaf rust and stem rust. More recently, this segment has been associated with resistance to wheat blast, an emerging and devastating wheat disease in South America and Asia. To date, full characterization of the segment including its size, gene content and its association with grain yield is lacking. Here, we present a complete cytological and physical characterization of this agronomically important translocation in bread wheat. We de novo assembled the 2N v S segment in two wheat varieties, ‘Jagger’ and ‘CDC Stanley,’ and delineated the segment to be approximately 33 Mb. A total of 535 high-confidence genes were annotated within the 2N v S region, with > 10% belonging to the nucleotide-binding leucine-rich repeat (NLR) gene families. Identification of groups of NLR genes that are potentially N genome-specific and expressed in specific tissues can fast-track testing of candidate genes playing roles in various disease resistances. We also show the increasing frequency of 2N v S among spring and winter wheat breeding programs over two and a half decades, and the positive impact of 2N v S on wheat grain yield based on historical datasets. The significance of the 2N v S segment in wheat breeding due to resistance to multiple diseases and a positive impact on yield highlights the importance of understanding and characterizing the wheat pan-genome for better insights into molecular breeding for wheat improvement.more » « less
-
more » « less
Abstract Plant disease resistance proteins (R‐proteins) detect specific pathogen‐derived molecules, triggering a defence response often including a rapid localized cell death at the point of pathogen penetration called the hypersensitive response (HR). The maize
Rp1‐D21 gene encodes a protein that triggers a spontaneous HR causing spots on leaves in the absence of any pathogen. Previously, we used fine mapping and functional analysis in aNicotiana benthamiana transient expression system to identify and characterize a number of genes associated with variation inRp1‐D21 ‐induced HR. Here we describe a system for characterizing genes mediating HR, using virus‐induced gene silencing (VIGS) in a maize line carryingRp1‐D21 . We assess the roles of 12 candidate genes. Three of these genes,SGT1 ,RAR1 , andHSP90 , are required for HR induced by a number of R‐proteins across several plant–pathogen systems. We confirmed that maize HSP90 was required for fullRp1‐D21 ‐induced HR. However, suppression of SGT1 expression unexpectedly increased the severity ofRp1‐D21 ‐induced HR while suppression of RAR1 expression had no measurable effect. We confirmed the effects on HR of two genes we had previously validated in theN. benthamiana system,hydroxycinnamoyltransferase andcaffeoyl CoA O‐methyltransferase . We further showed the suppression the expression of two previously uncharacterized, candidate genes,IQ calmodulin binding protein (IQM3 ) andvacuolar protein sorting protein 37 , suppressedRp1‐D21 ‐induced HR. This approach is an efficient way to characterize the roles of genes modulating the hypersensitive defence response and other dominant lesion phenotypes in maize.
