title: 18S-28S rDNA is interspersed throughout heterochromatin in the millipede Enologus oxypygum (Diplopoda).
abstract: In the present study, somatic metaphase chromosomes of the millipede Enologus oxypygum (Diplopoda: Julida) were hybridized in situ with a sea urchin (Echinodermata) ribosomal probe (prR14) in order to map major RNA genes (rDNA). Chromosomal preparations were also silver stained (Ag-NOR) to evaluate the rDNA transcriptional activity. Our results indicate that RNA genes are throughout heterochromatin in eight chromosomes involving 1/4 of the total heterochromatin which, in this species, is about 67% of the total DNA. Ag-NOR and FISH patterns were not coincident.
authors.affiliation: Dipartimento di Biologia Animale, Università di Palermo, Italy. zuvitcol@unipa.it
authors.forename: R
authors.initials: R
authors.lastname: Vitturi
authors.forename: M S
authors.initials: MS
authors.lastname: Colomba
authors.forename: M
authors.initials: M
authors.lastname: Mandrioli
authors.forename: A M
authors.initials: AM
authors.lastname: Pirrone
authors.forename: G
authors.initials: G
authors.lastname: Grispo
authors.forename: R
authors.initials: R
authors.lastname: Barbieri
mesh_terms: D000818:Animals; D001181:Arthropods / Q000235:genetics*; D004275:DNA, Ribosomal / Q000235:genetics; D006570:Heterochromatin / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D012337:RNA, Ribosomal, 18S / Q000235:genetics*; D012339:RNA, Ribosomal, 28S / Q000235:genetics*
chemical_list: D004275:DNA, Ribosomal; D006570:Heterochromatin; D012337:RNA, Ribosomal, 18S; D012339:RNA, Ribosomal, 28S