title: Fluorescence in situ hybridization of rDNA, telomeric (TTAGGG)n and (GATA)n repeats in the red abalone Haliotis rufescens (Archaeogastropoda: Haliotidae).
abstract: The physical location of 18S-5.8S-28S rDNA, telomeric sequences with (TTAGGG)n DNA probe and (GATA)n microsatellites were performed by fluorescence in situ hybridization in chromosomes of red abalone Haliotis rufescens. The karyotype of red abalone showed a diploid number of 36 (8M+9SM+1ST). FISH performed with rDNA probe, showed the location of major ribosomal clusters in the terminal region of the large arms of two submetacentric pairs (chromosome 4 and 5). Localization of heteromorphisms of FISH-rDNA was found between chromosome homologues and sister chromatids in all metaphases analyzed. This indicates that rDNA clusters are variable within the red abalone genome. The variability in the NOR-bearing reported using silver staining in other gastropods and our result are discussed. In addition, the presence of microsatellite (TTAGGG)n and (GATA)n was demonstrated after FISH treatment by DNA probes. The telomeric sequence occurred at the ends of all mitotic chromosomes, while the (GATA)n repetitive was found on chromosomal interstitial zones as well as at the telomeres in abalone chromosomes.
authors.affiliation: Departamento de Acuicultura. División de Oceanología, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, Ensenada, BC Mexico.
authors.forename: Cristian
authors.initials: C
authors.lastname: Gallardo-Escárate
authors.forename: Josué
authors.initials: J
authors.lastname: Alvarez-Borrego
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: del Río-Portilla
authors.forename: Ismael
authors.initials: I
authors.lastname: Cross
authors.forename: Alejandro
authors.initials: A
authors.lastname: Merlo
authors.forename: Laureana
authors.initials: L
authors.lastname: Rebordinos
mesh_terms: D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D004275:DNA, Ribosomal / Q000235:genetics*; D049851:Gastropoda / Q000235:genetics*; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D032681:Spectral Karyotyping; D016615:Telomere / Q000235:genetics*
chemical_list: D004275:DNA, Ribosomal