Evolution of Fusarium tricinctum and Fusarium avenaceum mitochondrial genomes is driven by mobility of introns and of a new type of palindromic microsatellite repeats

作者：Nadia Ponts, Charlotte Gautier, Jérôme Gouzy, Laëtitia Pinson‐Gadais, Marie Foulongne‐Oriol, Christine Ducos, Florence Richard‐Forget, Jean‐Michel Savoie, Zhao Chen, Gérard Barroso · 发表于：BMC Genomics · 年份：2020 · DOI：10.1186/s12864-020-6770-2 · 被引用次数：31 · 研究领域：Mycotoxins in Agriculture and Food、RNA and protein synthesis mechanisms、Fungal and yeast genetics research

Abstract Background Increased contamination of European and Asian wheat and barley crops with “emerging” mycotoxins such as enniatins or beauvericin, produced by Fusarium avenaceum and Fusarium tricinctum, suggest that these phylogenetically close species could be involved in future food-safety crises. Results The mitochondrial genomes of F. tricinctum strain INRA104 and F. avenaceum strain FaLH27 have been annotated. A comparative analysis was carried out then extended to a set of 25 wild strains. Results show that they constitute two distinct species, easily distinguished by their mitochondrial sequences. The mitochondrial genetic variability is mainly located within the intergenic regions. Marks of variations show they have evolved (i) by Single Nucleotide Polymorphisms (SNPs), (ii) by length variations mediated by insertion/deletion sequences (Indels), and (iii) by length mutations generated by DNA sliding events occurring in mononucleotide (A) n or (T) n microsatellite type sequences arranged in a peculiar palindromic organization. The optionality of these palindromes between both species argues for their mobility. The presence of Indels and SNPs in palindrome neighbouring regions suggests their involvement in these observed variations. Moreover, the intraspecific and interspecific variations in the presence/absence of group I introns suggest a high mobility, resulting from several events of gain and loss during short evolution periods. Phylogenetic analyses of intron or...