The Journal of Heredity 2002:93(4)
© 2002 The American Genetic Association 93:279-282
Brief Communication |
rDNA (18S28S and 5S) Colocalization and Linkage Between Ribosomal Genes and (TTAGGG)n Telomeric Sequence in the Earthworm, Octodrilus complanatus (Annelida: Oligochaeta: Lumbricidae), Revealed by Single- and Double-Color FISH
From the Dipartimento di Biologia Animale, Università di Palermo, Palermo, Italy (Vitturi); Facoltà di Scienze Ambientali, Università di Urbino, Urbino (PU), Italy (Colomba); Dipartimento di Biologia Cellulare e dello Sviluppo A. Monroy', Università di Palermo, Palermo, Italy (Pirrone); and Dipartimento di Biologia Animale, Università di Modena e Reggio Emilia, Modena, Italy (Mandrioli).
Address correspondence to Roberto Vitturi, Dipartimento di Biologia Animale, Via Archirafi 18, 90123 Palermo, Italy, or e-mail: zuvitcol{at}unipa.it.
Spermatogonial and metaphase I chromosomes of the lumbricid earthworm Octodrilus complanatus (Annelida: Oligochaeta) were examined using fluorescent in situ hybridization (FISH) with three repetitive DNA probes5S rDNA, 18S26S rDNA, and (TTAGGG)n. Single-color FISH consistently mapped one chromosome pair per spread using either 5S rDNA or 18S26S rDNA as probes. Simultaneous (18S26S)-5S and (18S26S)-(TTAGGG)n FISH demonstrated that repeated units of the two ribosomal families were overlapped and closely associated with telomeric sequences.