Sorghum is an important food and feed crop globally; its production is hampered by anthracnose disease caused by the fungal pathogen
Sorghum anthracnose caused by the fungus
- Award ID(s):
- 1916893
- NSF-PAR ID:
- 10480814
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 118
- Issue:
- 1
- ISSN:
- 0960-7412
- Format(s):
- Medium: X Size: p. 106-123
- Size(s):
- p. 106-123
- Sponsoring Org:
- National Science Foundation
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SUMMARY Colletotrichum sublineola (Cs ). Here, we report identification and characterization ofANTHRACNOSE RESISTANCE GENE 2 (ARG2 ) encoding a nucleotide‐binding leucine‐rich repeat (NLR) protein that confers race‐specific resistance toCs strains.ARG2 is one of a cluster of severalNLR genes initially identified in the sorghum differential line SC328C that is resistant to someCs strains. This cluster shows structural and copy number variations in different sorghum genotypes. Different sorghum lines carrying independentARG2 alleles provided the genetic validation for the identity of theARG2 gene.ARG2 expression is induced byCs , and chitin inducesARG2 expression in resistant but not in susceptible lines. ARG2‐mediated resistance is accompanied by higher expression of defense and secondary metabolite genes at early stages of infection, and anthocyanin and zeatin metabolisms are upregulated in resistant plants. Interestingly, ARG2 localizes to the plasma membrane when transiently expressed inNicotiana benthamiana . Importantly,ARG2 plants produced higher shoot dry matter than near‐isogenic lines carrying the susceptible allele suggesting an absence of anARG2 associated growth trade‐off. Furthermore, ARG2‐mediated resistance is stable at a wide range of temperatures. Our observations open avenues for resistance breeding and for dissecting mechanisms of resistance. -
Abstract Species in the genus
Macaca typically live in multimale‐multifemale social groups with male macaques exhibiting some of the largest testis: body weight ratios among primates. Males are believed to experience intense levels of sperm competition. Several spermatogenesis genes are located on the Y‐chromosome and, interestingly, occasional hybridization between two species has led to the introgression of the rhesus macaque (Macaca mulatta ) Y‐chromosome deep into the range of the long‐tailed macaque (M .fascicularis ). These observations have led to the prediction that the successful introgression of the rhesus Y‐haplotype is due to functional differences in spermatogenesis genes compared to those of the native long‐tailed Y‐haplotype. We examine here four Y‐chromosomal loci—RBMY ,XKRY , and two nearly identical copies ofCDY —and their corresponding protein sequences. The genes were surveyed in representative animals from north of, south of, and within the rhesus x long‐tailed introgression zone. Our results show a series of non‐synonymous amino acid substitutions present between the two Y‐haplotypes. Protein structure modeling via I‐TASSER revealed different folding patterns between the two species' Y‐proteins, and functional predictions via TreeSAAP further reveal physicochemical differences as a result of non‐synonymous substitutions. These differences inform our understanding of the evolution of primate Y‐proteins involved in spermatogenesis and, in turn, have biomedical implications for human male fertility. -
Abstract Goss's wilt, caused by the Gram-positive actinobacterium Clavibacter nebraskensis, is an important bacterial disease of maize. The molecular and genetic mechanisms of resistance to the bacterium, or, in general, Gram-positive bacteria causing plant diseases, remain poorly understood. Here, we examined the genetic basis of Goss's wilt through differential gene expression, standard genome-wide association mapping (GWAS), extreme phenotype (XP) GWAS using highly resistant (R) and highly susceptible (S) lines, and quantitative trait locus (QTL) mapping using 3 bi-parental populations, identifying 11 disease association loci. Three loci were validated using near-isogenic lines or recombinant inbred lines. Our analysis indicates that Goss's wilt resistance is highly complex and major resistance genes are not commonly present. RNA sequencing of samples separately pooled from R and S lines with or without bacterial inoculation was performed, enabling identification of common and differential gene responses in R and S lines. Based on expression, in both R and S lines, the photosynthesis pathway was silenced upon infection, while stress-responsive pathways and phytohormone pathways, namely, abscisic acid, auxin, ethylene, jasmonate, and gibberellin, were markedly activated. In addition, 65 genes showed differential responses (up- or down-regulated) to infection in R and S lines. Combining genetic mapping and transcriptional data, individual candidate genes conferring Goss's wilt resistance were identified. Collectively, aspects of the genetic architecture of Goss's wilt resistance were revealed, providing foundational data for mechanistic studies.
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Abstract Antimicrobial resistance is rapidly expanding, in a large part due to mobile genetic elements. We screened 94 fecal fluoroquinolone-resistant
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Abstract Background The sugarcane aphid (SCA;
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