title: Heterochromatin base pair composition and diversification in holocentric chromosomes of kissing bugs (Hemiptera, Reduviidae).
abstract: The subfamily Triatominae (Hemiptera, Reduviidae) includes 150 species of blood-sucking insects, vectors of Chagas disease or American trypanosomiasis. Karyotypic information reveals a striking stability in the number of autosomes. However, this group shows substantial variability in genome size, the amount and distribution of C-heterochromatin, and the chromosome positions of 45S rDNA clusters. Here, we analysed the karyotypes of 41 species from six different genera with C-fluorescence banding in order to evaluate the base-pair richness of heterochromatic regions. Our results show a high heterogeneity in the fluorescent staining of the heterochromatin in both autosomes and sex chromosomes, never reported before within an insect subfamily with holocentric chromosomes. This technique allows a clear discrimination of the heterochromatic regions classified as similar by C-banding, constituting a new chromosome marker with taxonomic and evolutionary significance. The diverse fluorescent patterns are likely due to the amplification of different repeated sequences, reflecting an unusual dynamic rearrangement in the genomes of this subfamily. Further, we discuss the evolution of these repeated sequences in both autosomes and sex chromosomes in species of Triatominae.
authors.affiliation: Universidade Estadual Paulista, Instituto de Biociências, Departamento de Biologia, Rio Claro, SP, Brasil.
authors.forename: Vanessa Bellini
authors.initials: VB
authors.lastname: Bardella
authors.affiliation: Universidad de la República, Facultad de Ciencias, Sección Genética Evolutiva, Montevideo, Uruguay.
authors.forename: Sebastián
authors.initials: S
authors.lastname: Pita
authors.affiliation: Universidade Estadual de Londrina, Centro de Ciências Biológicas, Departamento de Biologia Geral, Londrina, PR, Brasil.
authors.forename: André Luis Laforga
authors.initials: AL
authors.lastname: Vanzela
authors.affiliation: Instituto Oswaldo Cruz, Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos, Rio de Janeiro, RJ, Brasil.
authors.forename: Cleber
authors.initials: C
authors.lastname: Galvão
authors.affiliation: Universidad de la República, Facultad de Ciencias, Sección Genética Evolutiva, Montevideo, Uruguay.
authors.forename: Francisco
authors.initials: F
authors.lastname: Panzera
mesh_terms: D000818:Animals; D005075:Biological Evolution; D014355:Chagas Disease / Q000635:transmission; D059006:Chromosomes, Insect / Q000235:genetics*; D004275:DNA, Ribosomal / Q000235:genetics; D006570:Heterochromatin / Q000235:genetics*; D007303:Insect Vectors / Q000235:genetics*; D007621:Karyotyping; D012335:RNA, Ribosomal / Q000235:genetics; D014225:Triatominae / Q000145:classification / Q000235:genetics*
chemical_list: D004275:DNA, Ribosomal; D006570:Heterochromatin; D012335:RNA, Ribosomal; C088179:RNA, ribosomal, 45S