Cytogenetics in Brachidontes rodriguezi d'Orb (Bivalvia, Mytilidae)

Citation
A. Torreiro et al., Cytogenetics in Brachidontes rodriguezi d'Orb (Bivalvia, Mytilidae), CHROMOS RES, 7(1), 1999, pp. 49-55
Citations number
29
Categorie Soggetti
Molecular Biology & Genetics
Journal title
CHROMOSOME RESEARCH
ISSN journal
09673849 → ACNP
Volume
7
Issue
1
Year of publication
1999
Pages
49 - 55
Database
ISI
SICI code
0967-3849(1999)7:1<49:CIBRD(>2.0.ZU;2-P
Abstract
The chromosomes of Brachidontes rodriguezi were analysed by means of direct Giemsa staining, silver staining, fluorescent in-situ hybridization (FISH) with 18S + 28S rDNA probes, replication banding and chromomycin A3 (CMA) a nd DAPI fluorescence banding techniques. The diploid chromosome number in t his species is 32 and the karyotype is composed of two pairs of metacentric chromosomes, 2 pairs of telo/subtelocentric chromosomes and 12 pairs of su btelocentric chromosomes. 18S + 28S rDNA clusters were located on the short arms of the two pairs of telo/subtelocentric chromosomes. The replication band pattern induced in this species facilitates chromosome pairing and dif ferentiation. The nucleolar organizing regions (NORs) replicate late in the S phase and were associated with bright CMA fluorescence and dull DAPI flu orescence, but not all the four NORs showed bright CMA fluorescence in a gi ven cell; intra- and interindividual variability was found for this charact er.