Evolution and organization of a highly dynamic, subtelomeric helicase gene family in the rice blast fungus Magnaporthe grisea.
نویسندگان
چکیده
Sequence analysis of a 13-kb telomeric region in O-137, a rice pathogenic isolate of Magnaporthe grisea, uncovered a novel gene, designated TLH1 (telomere-linked helicase 1). The TLH1 gene is a member of a gene family, and the sequences flanking this gene family have also been amplified. Genetic mapping showed that most members of the TLH gene family are tightly linked to the telomeres. A physical mapping technique, termed RecA-mediated Achilles' heel cleavage, and cloning and sequencing of two additional telomeres of O-137 associated with the TLH gene family confirmed that most members of the TLH gene family are located within 10 kb from the telomeric repeat. A survey of M. grisea strains from diverse hosts revealed that the gene family is ubiquitously present among rice pathogens, but is absent from almost all isolates of hosts other than rice. The gene family appears to be highly dynamic, undergoing frequent deletion/amplification events. Given the presence of similar helicase gene families in chromosome ends of Saccharomyces cerevisiae and Ustilago maydis, the initial association of helicase genes with fungal telomeres might date back to very early stages of the fungal evolution.
منابع مشابه
Characterization and Phylogenetic Analysis of Magnaporthe spp. strains on Various Hosts in Iran
Background: Populations of Magnaporthe, the causal agent of rice blast disease, are pathotypically and genetically diverse and therefore their interaction with different rice cultivars and also antagonistic microorganisms are very complicated. Objectives: The objectives of the present study were to characterize phylogenetic relationships of 114 native Magnaporthe strains, isolated from rice a...
متن کاملPathogen-induced production of the antifungal AFP protein from Aspergillus giganteus confers resistance to the blast fungus Magnaporthe grisea in transgenic rice.
Rice blast, caused by Magnaporthe grisea, is the most important fungal disease of cultivated rice worldwide. We have developed a strategy for creating disease resistance to M. grisea whereby pathogen-induced expression of the afp (antifungal protein) gene from Aspergillus giganteus occurs in transgenic rice plants. Here, we evaluated the activity of the promoters from three maize pathogenesis-r...
متن کاملChlorimuronethyl Resistance Selectable Marker Unsuited for the Transformation of Rice Blast Fungus (Magnaporthe Grisea)
Chlorimuronethyl resistance gene is increasingly used as a selectable marker for transformation, especially fungal transformation. Magnaporthe grisea is an important model organism for investigating fungal pathogenicity, and Agrobacterium tumefaciens-mediated transformation (ATMT) is used for functional mutagenesis of the fungus. However, our results showed that rice blast strains collected fro...
متن کاملRegulatory Genes Controlling MPG1 Expression and Pathogenicity in the Rice Blast Fungus Magnaporthe grisea.
MPG1, a pathogenicity gene of the rice blast fungus Magnaporthe grisea, is expressed during pathogenesis and in axenic culture during nitrogen or glucose limitation. We initiated a search for regulatory mutations that would impair nitrogen metabolism, MPG1 gene expression, and pathogenicity. First, we developed a pair of laboratory strains that were highly fertile and pathogenic toward barley. ...
متن کاملComparative Analysis of Pathogenicity, Phylogenetic Relationship and Host Fungal Rice Blast Pathogen Magnaporthe grisea
Magnaporthe grisea, also identified as rice blast fungus, rotten rice neck, rice seedling blight, oval leaf spot of graminea, blast of rice [1], pitting disease, ryegrass blast, and Johnson spot is a plant-pathogenic fungus that causes a serious disease affecting rice [2]. Rice blast, caused by Magnaporthe grisea, is considered the most important disease of rice worldwide [3] because of its ext...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Genetics
دوره 162 1 شماره
صفحات -
تاریخ انتشار 2002