scholarly journals Delineating the elusive BaMMV resistance gene rym15 in barley by medium-resolution mapping

2021 ◽  
Vol 41 (12) ◽  
Author(s):  
Yaping Wang ◽  
Antje Habekuß ◽  
Rod J. Snowdon ◽  
Frank Ordon ◽  
Dragan Perovic
Keyword(s):  
Resistance Gene ◽  
Reference Genome ◽  
Gene Identification ◽  
Polymyxa Graminis ◽  
Genome Wide ◽  
Medium Resolution ◽  
Segregation Ratios ◽  
Resolution Mapping ◽  
Mild Mosaic Virus ◽  
Mapping Populations

Abstract Barley mild mosaic virus (BaMMV), transmitted by the soil-borne protist Polymyxa graminis, has a serious impact on winter barley production. Previously, the BaMMV resistance gene rym15 was mapped on chromosome 6HS, but the order of flanking markers was non-collinear between different maps. To resolve the position of the flanking markers and to enable map-based cloning of rym15, two medium-resolution mapping populations Igri (susceptible) × Chikurin Ibaraki 1 (resistant) (I × C) and Chikurin Ibaraki 1 × Uschi (susceptible) (C × U), consisting of 342 and 180 F2 plants, respectively, were developed. Efficiency of the mechanical inoculation of susceptible standards varied from 87.5 to 100% and in F2 populations from 90.56 to 93.23%. Phenotyping of F2 plants and corresponding F3 families revealed segregation ratios of 250 s:92r (I × C, χ2 = 0.659) and 140 s:40r (C × U, χ2 = 0.741), suggesting the presence of a single recessive resistance gene. After screening the parents with the 50 K Infinium chip and anchoring corresponding SNPs to the barley reference genome, 8 KASP assays were developed and used to remap the gene. Newly constructed maps revealed a collinear order of markers, thereby allowing the identification of high throughput flanking markers. This study demonstrates how construction of medium-resolution mapping populations in combination with robust phenotyping can efficiently resolve conflicting marker ordering and reduce the size of the target interval. In the reference genome era and genome-wide genotyping era, medium-resolution mapping will help accelerate candidate gene identification for traits where phenotyping is difficult.

scholarly journals Delineating the Elusive BaMMV Resistance Gene rym15 in Barley by Medium-Resolution Mapping

2021 ◽  
Author(s):  
Yaping Wang ◽  
Antje Habekuss ◽  
Rod J Snowdon ◽  
Frank Ordon ◽  
Dragan Perovic
Keyword(s):  
Resistance Gene ◽  
High Throughput ◽  
Reference Genome ◽  
Gene Identification ◽  
Polymyxa Graminis ◽  
Medium Resolution ◽  
Resolution Mapping ◽  
Mild Mosaic Virus ◽  
Reference Genomes ◽  
Mapping Populations

Abstract Barley mild mosaic virus (BaMMV), transmitted by the soil-borne protist Polymyxa graminis, has a serious impact on winter barley production. Previously, the BaMMV resistance gene rym15 was mapped on chromosome 6HS, but the order of flanking markers was non-collinear between different maps. To resolve the position of the flanking markers and to enable map-based cloning of rym15, two medium-resolution mapping populations Igri (susceptible) × Chikurin Ibaraki 1 (resistant) (I×C) and Chikurin Ibaraki 1 × Uschi (susceptible) (C×U), consisting of 342 and 180 F2 plants, respectively, were developed. Efficiency of the mechanical inoculation at susceptible standards varied from 87.5–100% and in F2 populations from 90.56–93.23%. Phenotyping of F2 plants and corresponding F3 families revealed segregation ratios of 250s:92r (I×C, χ2 = 0.659) and 140s:40r (C×U, χ2 = 0.741), suggesting the presence of a single recessive resistance gene. Eight KASP assays, developed after screening the parents with the 50K Infinium chip and anchoring corresponding SNPs to the barley reference genome, were used to remap the gene. Newly constructed maps revealed a collinear order of markers, thereby allowing the identification of high throughput flanking markers. This study demonstrates how construction of medium-resolution mapping populations in combination with robust phenotyping can efficiently resolve conflicting marker ordering and reduce the size of the target interval. In an era of reference genomes and high throughput marker platforms, medium-resolution mapping will help accelerate candidate gene identification for traits where phenotyping is difficult.

scholarly journals Genome assembly of the JD17 soybean provides a new reference genome for Comparative genomics

2021 ◽  
Author(s):  
Xinxin Yi ◽  
Jing Liu ◽  
Shengcai Chen ◽  
Hao Wu ◽  
Min Liu ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Genome Assembly ◽  
Reference Genome ◽  
De Novo ◽  
Genomic Analysis ◽  
Comparative Genomic ◽  
High Quality ◽  
Genome Wide ◽  
A Genome ◽  
Cultivated Soybean

Cultivated soybean (Glycine max) is an important source for protein and oil. Many elite cultivars with different traits have been developed for different conditions. Each soybean strain has its own genetic diversity, and the availability of more high-quality soybean genomes can enhance comparative genomic analysis for identifying genetic underpinnings for its unique traits. In this study, we constructed a high-quality de novo assembly of an elite soybean cultivar Jidou 17 (JD17) with chromsome contiguity and high accuracy. We annotated 52,840 gene models and reconstructed 74,054 high-quality full-length transcripts. We performed a genome-wide comparative analysis based on the reference genome of JD17 with three published soybeans (WM82, ZH13 and W05) , which identified five large inversions and two large translocations specific to JD17, 20,984 - 46,912 PAVs spanning 13.1 - 46.9 Mb in size, and 5 - 53 large PAV clusters larger than 500kb. 1,695,741 - 3,664,629 SNPs and 446,689 - 800,489 Indels were identified and annotated between JD17 and them. Symbiotic nitrogen fixation (SNF) genes were identified and the effects from these variants were further evaluated. It was found that the coding sequences of 9 nitrogen fixation-related genes were greatly affected. The high-quality genome assembly of JD17 can serve as a valuable reference for soybean functional genomics research.

scholarly journals Genome-wide investigation of heat shock transcription factor family in wheat (Triticum aestivum L.)

2019 ◽  
Author(s):  
Jiali Ye ◽  
Xuetong Yang ◽  
Sha Li ◽  
Wei Li ◽  
Qi Liu ◽  
...  
Keyword(s):  
Heat Shock ◽  
Reference Genome ◽  
Phylogenetic Analyses ◽  
Triticum Aestivum L ◽  
Growth Stages ◽  
Rna Seq ◽  
Male Sterile ◽  
Heat Shock Transcription Factors ◽  
Genome Wide ◽  
Resistance To Heat

Abstract Background: Heat shock transcription factors (HSFs) play crucial roles in resisting heat stress and regulating plant development. Investigating the HSF family is essential for understanding the fertility conversion mechanism in thermo-sensitive male sterile wheat. Previous studies have investigated the HSF family in wheat but it is necessary to conduct more in-depth and systematic analyses based on the newly published reference genome. Results: In the present study, 61 wheat Hsf (TaHsf) genes were identified using two main strategies and renamed based on their physical locations on chromosomes. According to the gene structure and phylogenetic analyses, the 61 TaHsf genes were classified into three categories and eleven subclasses. The genes were unequally distributed on 21 chromosomes, including two pairs of tandem duplication genes and 52 TaHsf segmental duplication genes. According to the cis-elements identified, most of the TaHsfs can be activated by Ca++ and MYB, and they respond to drought, light, copper, and other stresses as well as heat shock. RNA-seq analysis indicated that the A2 class TaHsf genes exhibited persistently upregulated expression levels in the leaves/shoots, roots (except in the vegetative growth and reproductive growth stages), spikes, and grains in wheat under normal conditions. The A and B class TaHsf genes were positively regulated during the resistance to heat, whereas the C class genes were involved in drought regulation in wheat. Only the A and B class TaHsf genes were upregulated under fertile conditions in thermo-sensitive male sterile wheat. Conclusion: In this study, 61 wheat Hsf genes were identified based on the complete wheat reference genome. This comprehensive analysis provides novel insights into the TaHsf genes, including their diverse functions and involvement in metabolic pathways.

scholarly journals Identifying Nootropic Drug Targets via Large-Scale Cognitive GWAS and Transcriptomics

2020 ◽  
Author(s):  
Max Lam ◽  
Chen Chia-Yen ◽  
Xia Yan ◽  
W. David Hill ◽  
Joey W. Trampush ◽  
...  
Keyword(s):  
Cognitive Ability ◽  
Drug Targets ◽  
Large Scale ◽  
Drug Repurposing ◽  
Gene Identification ◽  
Summary Statistics ◽  
General Cognitive Ability ◽  
Nootropic Drug ◽  
Genome Wide ◽  
Meta Analyses

AbstractBackgroundCognitive traits demonstrate significant genetic correlations with many psychiatric disorders and other health-related traits. Many neuropsychiatric and neurodegenerative disorders are marked by cognitive deficits. Therefore, genome-wide association studies (GWAS) of general cognitive ability might suggest potential targets for nootropic drug repurposing. Our previous effort to identify “druggable genes” (i.e., GWAS-identified genes that produce proteins targeted by known small molecules) was modestly powered due to the small cognitive GWAS sample available at the time. Since then, two large cognitive GWAS meta-analyses have reported 148 and 205 genome-wide significant loci, respectively. Additionally, large-scale gene expression databases, derived from post-mortem human brain, have recently been made available for GWAS annotation. Here, we 1) reconcile results from these two cognitive GWAS meta-analyses to further enhance power for locus discovery; 2) employ several complementary transcriptomic methods to identify genes in these loci with variants that are credibly associated with cognition; and 3) further annotate the resulting genes to identify “druggable” targets.MethodsGWAS summary statistics were harmonized and jointly analysed using Multi-Trait Analysis of GWAS [MTAG], which is optimized for handling sample overlaps. Downstream gene identification was carried out using MAGMA, S-PrediXcan/S-TissueXcan Transcriptomic Wide Analysis, and eQTL mapping, as well as more recently developed methods that integrate GWAS and eQTL data via Summary-statistics Mendelian Randomization [SMR] and linkage methods [HEIDI], Available brain-specific eQTL databases included GTEXv7, BrainEAC, CommonMind, ROSMAP, and PsychENCODE. Intersecting credible genes were then annotated against multiple chemoinformatic databases [DGIdb, KI, and a published review on “druggability”].ResultsUsing our meta-analytic data set (N = 373,617) we identified 241 independent cognition-associated loci (29 novel), and 76 genes were identified by 2 or more methods of gene identification. 26 genes were associated with general cognitive ability via SMR, 16 genes via STissueXcan/S-PrediXcan, 47 genes via eQTL mapping, and 68 genes via MAGMA pathway analysis. The use of the HEIDI test permitted the exclusion of candidate genes that may have been artifactually associated to cognition due to linkage, rather than direct causal or indirect pleiotropic effects. Actin and chromatin binding gene sets were identified as novel pathways that could be targeted via drug repurposing. Leveraging on our various transcriptome and pathway analyses, as well as available chemoinformatic databases, we identified 16 putative genes that may suggest drug targets with nootropic properties.DiscussionResults converged on several categories of significant drug targets, including serotonergic and glutamatergic genes, voltage-gated ion channel genes, carbonic anhydrase genes, and phosphodiesterase genes. The current results represent the first efforts to apply a multi-method approach to integrate gene expression and SNP level data to identify credible actionable genes for general cognitive ability.

Sign in / Sign up

Export Citation Format

Share Document