scholarly journals A recombined Sr26 and Sr61 disease resistance gene stack in wheat encodes unrelated NLR genes

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jianping Zhang ◽  
Timothy C. Hewitt ◽  
Willem H. P. Boshoff ◽  
Ian Dundas ◽  
Narayana Upadhyaya ◽  
...  

AbstractThe re-emergence of stem rust on wheat in Europe and Africa is reinforcing the ongoing need for durable resistance gene deployment. Here, we isolate from wheat, Sr26 and Sr61, with both genes independently introduced as alien chromosome introgressions from tall wheat grass (Thinopyrum ponticum). Mutational genomics and targeted exome capture identify Sr26 and Sr61 as separate single genes that encode unrelated (34.8%) nucleotide binding site leucine rich repeat proteins. Sr26 and Sr61 are each validated by transgenic complementation using endogenous and/or heterologous promoter sequences. Sr61 orthologs are absent from current Thinopyrum elongatum and wheat pan genome sequences, contrasting with Sr26 where homologues are present. Using gene-specific markers, we validate the presence of both genes on a single recombinant alien segment developed in wheat. The co-location of these genes on a small non-recombinogenic segment simplifies their deployment as a gene stack and potentially enhances their resistance durability.

Genome ◽  
1997 ◽  
Vol 40 (5) ◽  
pp. 659-665 ◽  
Author(s):  
Evans S. Lagudah ◽  
Odile Moullet ◽  
Rudi Appels

The Cre3 gene confers a high level of resistance to the root endoparasitic nematode Heterodera avenae in wheat. A DNA marker cosegregating with H. avenae resistance was used as an entry point for map-based cloning of a disease resistance gene family at the Cre3 locus. Two related gene sequences have been analysed at the Cre3 locus. One, identified as a cDNA clone, encodes a polypeptide with a nucleotide binding site (NBS) and a leucine-rich region; this member of the disease resistance gene family is expressed in roots. A second Cre3 gene sequence, cloned as genomic DNA, appears to be a pseudogene, with a frame shift caused by a deletion event. These two genes, related to members of the cytoplasmic NBS – leucine rich repeat class of plant disease resistance genes were physically mapped to the distal 0.06 fragment of the long arm of wheat chromosome 2D and cosegregated with nematode resistance.Key words: cereal cyst nematode, disease resistance genes, nucleotide-binding site, leucine-rich repeat.


1998 ◽  
Vol 10 (11) ◽  
pp. 1915
Author(s):  
Mark S. Dixon ◽  
Kostas Hatzixanthis ◽  
David A. Jones ◽  
Kate Harrison ◽  
Jonathan D. G. Jones

Genome ◽  
1999 ◽  
Vol 42 (4) ◽  
pp. 735-743 ◽  
Author(s):  
A Joyeux ◽  
M G Fortin ◽  
R Mayerhofer ◽  
A G Good

Genetic mapping of plants traditionally involves the analysis of large segregating populations. However, not all individuals in a population contribute equal amounts of genetic information. It is thus possible to achieve rough mapping using a subset of the most informative individuals in the population. We have designed a minimal Brassica napus mapping population of 23 doubled-haploid plants and have tested this method using this population in the mapping of disease resistance gene homologues in B. napus. Several groups have identified such homologues in soybean and potato by amplifying sequences corresponding to conserved nucleotide-binding sites from known resistance genes. However, the sequence conservation in the leucine-rich repeat domain that is present in most of the disease resistance genes isolated has not been exploited via the polymerase chain reaction (PCR). We present the genetic mapping of Brassica napus DNA sequences amplified with primers corresponding to both the nucleotide-binding site and the leucine rich-repeat domain of the Arabidopsis thaliana RPS2 gene. We also describe a method for the quick mapping of resistance gene homologues using the polymerase chain reaction.Key words: Brassica napus, disease resistance genes, minimal mapping population, RFLP markers.


2009 ◽  
Vol 134 (6) ◽  
pp. 649-657 ◽  
Author(s):  
Karen R. Harris ◽  
W. Patrick Wechter ◽  
Amnon Levi

Sixty-six watermelon (Citrullus lanatus var. lanatus) disease resistance gene analogs were cloned from ‘Calhoun Gray’, PI 296341, and PI 595203 using degenerate primers to select for the nucleotide binding sites (NBS) from the NBS–leucine-rich repeat (LRR) resistance gene family. After contig assembly, watermelon resistance gene analogs (WRGA) were identified and amino acid sequence alignment revealed that these groups contained motifs characteristic of NBS-LRR resistance genes. Using cluster analysis, eight groups of WRGA were identified and further characterized as having homology to Drosophila Toll and mammalian interleukin-1 receptor (TIR) and non-TIR domains. Three of these WRGA as well as three disease-related watermelon expressed sequence tag homologs were placed on a test-cross map. Linkage mapping placed the WRGA on linkage group XIII, an area on the watermelon map where resistance gene analogs cluster. In addition, these WRGA sequence-tagged sites (STS) were amplified from various genera of the Cucurbitaceae indicating that conservation of resistance gene analogs exists among cucurbits. These WRGA-STS markers may be useful in marker-assisted selection for the improvement for disease resistance in watermelon.


2014 ◽  
Vol 4 (1) ◽  
Author(s):  
Shuichi Fukuoka ◽  
Shin-Ichi Yamamoto ◽  
Ritsuko Mizobuchi ◽  
Utako Yamanouchi ◽  
Kazuko Ono ◽  
...  

1998 ◽  
Vol 10 (11) ◽  
pp. 1915-1925 ◽  
Author(s):  
Mark S. Dixon ◽  
Kostas Hatzixanthis ◽  
David A. Jones ◽  
Kate Harrison ◽  
Jonathan D. G. Jones

Sign in / Sign up

Export Citation Format

Share Document