engleski

Karyotype analysis in Hyacinthella dalmatica (HYACINTHACEAE) reveals vertebrate-type telomere repeats at the chromosome ends

Chromosome analysis of three different populations of Hyacinthella dalmatica (Lallem) Trinajstic, an endemic species of the coastal region of South-Eastern Europe, showed an unique chromosome number, 2n=2x=20, and bimodal karyotype with one large and nine smaller pairs of chromosomes. Staining with fluorochromes CMA_3 (chromomycin A_3) and DAPI (4.6-diamidino-2-phenylindole) revealed heterochromatic regions associated with NORs, centromeres, and several interstitial heterochromatic bands on the longest chromosome pair. Double target FISH with two ribosomal DNA probes revealed one locus of 5S rRNA genes in the pericentromeric region of the chromosome pair 3, and one locus of 18S-5.8S-26S rRNA genes on the short arm of chromosome pair 4, in all plants and populations analysed. Southern hybridization analysis and FISH experiments demonstrated that the distal ends of H. dalmatica chromosomes contain the vertebrate telomere (5´-TTAGGG-3´) repeat type rather than the Arabidopsis (5´-TTTAGGG-3´) heptamer, and so suggest that this Asparagales species along with Aloe and Othocalis contains the vertebrate-type telomere repeat.

Hyacinthaceae; Hyacinthella; chromosomes; ribosomal genes; telomeric repeats

nije evidentirano