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Effector gene reshuffling involves dispensable mini-chromosomes in the wheat blast fungus.

ABSTRACT: Newly emerged wheat blast disease is a serious threat to global wheat production. Wheat blast is caused by a distinct, exceptionally diverse lineage of the fungus causing rice blast disease. Through sequencing a recent field isolate, we report a reference genome that includes seven core chromosomes and mini-chromosome sequences that harbor effector genes normally found on ends of core chromosomes in other strains. No mini-chromosomes were observed in an early field strain, and at least two from another isolate each contain different effector genes and core chromosome end sequences. The mini-chromosome is enriched in transposons occurring most frequently at core chromosome ends. Additionally, transposons in mini-chromosomes lack the characteristic signature for inactivation by repeat-induced point (RIP) mutation genome defenses. Our results, collectively, indicate that dispensable mini-chromosomes and core chromosomes undergo divergent evolutionary trajectories, and mini-chromosomes and core chromosome ends are coupled as a mobile, fast-evolving effector compartment in the wheat pathogen genome.

SUBMITTER: Peng Z

PROVIDER: S-EPMC6741851 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Effector gene reshuffling involves dispensable mini-chromosomes in the wheat blast fungus.

Peng Zhao Z Oliveira-Garcia Ely E Lin Guifang G Hu Ying Y Dalby Melinda M Migeon Pierre P Tang Haibao H Farman Mark M Cook David D White Frank F FF Valent Barbara B Liu Sanzhen S

PLoS genetics 20190912 9

Newly emerged wheat blast disease is a serious threat to global wheat production. Wheat blast is caused by a distinct, exceptionally diverse lineage of the fungus causing rice blast disease. Through sequencing a recent field isolate, we report a reference genome that includes seven core chromosomes and mini-chromosome sequences that harbor effector genes normally found on ends of core chromosomes in other strains. No mini-chromosomes were observed in an early field strain, and at least two from ...[more]

PMID: 31513573

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Dataset Information

Effector gene reshuffling involves dispensable mini-chromosomes in the wheat blast fungus.

Publications

Effector gene reshuffling involves dispensable mini-chromosomes in the wheat blast fungus.

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