title: Sequence analyses and chromosomal distribution of the Tc1/Mariner element in Parodontidae fish (Teleostei: Characiformes).
abstract: Transposable elements are able to move along eukaryotic genomes. They are divided into two classes according to their transposition intermediate: RNA (class I or retrotransposons) or DNA (class II or DNA transposons). Most of these sequences are inactive or non-autonomous in eukaryotic genomes. Inactivate transposons can accumulate mutations at neutral rates until losing their molecular identity. They may either be eliminated from the genome or take on different molecular functions. Transposable elements may also participate in the differentiation of sex chromosomes. Therefore, the structural variations and nucleotide similarity of Tc1/Mariner sequences were analyzed along with their potential participation in the differentiation processes of sex chromosomes in the genomes of Parodontidae fish. All Parodontidae species presented non-autonomous copies of Tc1/Mariner with structural variation, different levels of deterioration (genetic distance), and variations in insertion and deletion patterns. The physical mapping of Tc1/Mariner on chromosomes revealed dispersed signals in euchromatins, with small accumulations in terminal regions and in the sex chromosomes. The gene dosage ratios indicated copy number variations of Tc1/Mariner among the genomes and high transposase open reading frame deterioration in Parodon hilarii and Parodon pongoensis genomes. This transposon presented transcriptional activity in gonads, but there was no significant difference between sexes. This may indicate non-functional protein expression or may correspond to DNA binding proteins derived from Tc1/Mariner. Thus, our results show Tc1/Mariner inactivation along with a diversity in Parodontidae genomes and its participation in the differentiation of the W sex chromosome.
authors: Department of Genetics, Federal University of Paraná, Curitiba, Paraná, Brazil; Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Paraná, Brazil. Electronic address: miorane@hotmail.com.
authors: Michelle Orane
authors: MO
authors: Schemberger
authors: Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Paraná, Brazil.
authors: Viviane
authors: V
authors: Nogaroto
authors: Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Paraná, Brazil.
authors: Mara Cristina
authors: MC
authors: Almeida
authors: Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Paraná, Brazil.
authors: Roberto Ferreira
authors: RF
authors: Artoni
authors: Department of Bioprocess and Biotechnology, São Paulo State University, Botucatu, São Paulo, Brazil.
authors: Guilherme Targino
authors: GT
authors: Valente
authors: Department of Morphology, Institute of Biosciences, São Paulo State University, São Paulo, Brazil.
authors: Cesar
authors: C
authors: Martins
authors: Department of Genetics and Evolution, Federal University of São Carlos, São Carlos, São Paulo, Brazil.
authors: Orlando
authors: O
authors: Moreira-Filho
authors: Department of Genetics, Federal University of Paraná, Curitiba, Paraná, Brazil.
authors: Marta Margarete
authors: MM
authors: Cestari
authors: Department of Genetics, Federal University of Paraná, Curitiba, Paraná, Brazil; Department of Structural and Molecular Biology and Genetics, State University of Ponta Grossa, Ponta Grossa, Paraná, Brazil.
authors: Marcelo Ricardo
authors: MR
authors: Vicari
mesh_terms: D000818:Animals; D060125:Characiformes / Q000235:genetics*; D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D018628:Gene Dosage; D006066:Gonads / Q000378:metabolism; D008297:Male; D016366:Open Reading Frames; D011110:Polymorphism, Genetic; D012730:Sex Chromosomes / Q000235:genetics*; D019895:Transposases / Q000235:genetics* / Q000378:metabolism
chemical_list: D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins; D029941:Fish Proteins; C111652:mariner transposases; D019895:Transposases
keywords: Bioinformatics; Cytogenetic; Deterioration; Molecular analyses; Repetitive DNA; W chromosome