title: Transposable elements belonging to the Tc1-Mariner superfamily are heavily mutated in Colletotrichum graminicola.
abstract: Transposable elements are ubiquitous and constitute an important source of genetic variation in addition to generating deleterious mutations. Several filamentous fungi are able to defend against transposable elements using RIP(repeat-induced point mutation)-like mechanisms, which induce mutations in duplicated sequences. The sequenced Colletotrichum graminicola genome and the availability of transposable element databases provide an efficient approach for identifying and characterizing transposable elements in this fungus, which was the subject of this study. We identified 132 full-sized Tc1-Mariner transposable elements in the sequenced C. graminicola genome, which were divided into six families. Several putative transposases that have been found in these elements have conserved DDE motifs, but all are interrupted by stop codons. An in silico analysis showed evidence for RIP-generated mutations. The TCg1 element, which was cloned from the Brazilian 2908 m isolate, has a putative transposase sequence with three characteristic conserved motifs. However, this sequence is interrupted by five stop codons. Genomic DNA from various isolates was analyzed by hybridization with an internal region of TCg1. All of the isolates featured transposable elements that were similar to TCg1, and several hybridization profiles were identified. C. graminicola has many Tc1-Mariner transposable elements that have been degenerated by characteristic RIP mutations. It is unlikely that any of the characterized elements are autonomous in the sequenced isolate. The possible existence of active copies in field isolates from Brazil was shown. The TCg1 element is present in several C. graminicola isolates and is a potentially useful molecular marker for population studies of this phytopathogen.
authors.affiliation: Departamento de Microbiologia, Instituto de Ciências Biomédicas II, Universidade de São Paulo, Avenida Professor Lineu Prestes 1374, Cidade Universitária, São Paulo, Brasil. CEP: 05508-900.
authors.forename: Raíssa Mesquita
authors.initials: RM
authors.lastname: Braga
authors.affiliation: Departamento de Microbiologia, Universidade Federal de Viçosa, Avenida Peter Henry Rolfs s/n, Campus Universitário, Viçosa, Brasil. CEP: 36570-000.
authors.forename: Mateus Ferreira
authors.initials: MF
authors.lastname: Santana
authors.affiliation: Embrapa Milho e Sorgo, Rod MG 424 Km 65, Sete Lagoas, Minas Gerais, Brasil. CEP: 35701-970.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Veras da Costa
authors.affiliation: Departamento de Fitopatologia, Universidade Federal de Viçosa, Avenida Peter Henry Rolfs s/n, Campus Universitário, Viçosa, Brasil. CEP: 36570-000.
authors.forename: Sergio Herminio
authors.initials: SH
authors.lastname: Brommonschenkel
authors.affiliation: Fundação de Amparo à Pesquisa do Estado de Minas Gerais, Rua Raul Pompeia 101, São Pedro, Belo Horizonte, Brasil. CEP: 30330-080.
authors.forename: Elza Fernandes
authors.initials: EF
authors.lastname: de Araújo
authors.affiliation: Departamento de Microbiologia, Universidade Federal de Viçosa, Avenida Peter Henry Rolfs s/n, Campus Universitário, Viçosa, Brasil. CEP: 36570-000 mvqueiro@ufv.br.
authors.forename: Marisa Vieira
authors.initials: MV
authors.lastname: de Queiroz
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001483:Base Sequence; D001938:Brazil; D020231:Colletotrichum / Q000235:genetics*; D004251:DNA Transposable Elements / Q000235:genetics*; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics; D005819:Genetic Markers / Q000235:genetics; D014644:Genetic Variation; D016681:Genome, Fungal / Q000235:genetics*; D055029:Inverted Repeat Sequences / Q000235:genetics; D008969:Molecular Sequence Data; D009154:Mutation; D009693:Nucleic Acid Hybridization; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D019895:Transposases / Q000737:chemistry / Q000235:genetics*
chemical_list: D004251:DNA Transposable Elements; D004271:DNA, Fungal; D005656:Fungal Proteins; D005819:Genetic Markers; D019895:Transposases
keywords: RIP; transposase; transposon