The Zebrafish Science Monitor Vol 3(5)

CHROMOSOME COMPLEMENT, C-, AG- NOR AND REPLICATION BANDING IN THE ZEBRAFISH Danio rerio

By R.R. Daga1, G. Thode1 and A. Amores2 1Departamento de Genetica, Facultad de Ciencias, Universidad de Malaga, 29071- Malaga, SPAIN; 2Institute of Neuroscience, University of Oregon, Eugene, OR 97403- 1254, USA

(in press, Chromosome Research)

The chromosome complement of Danio rerio was investigated by Giemsa staining, C- banding (for constitutive heterochromatin), Ag- NOR (silver staining of Nucleolus Organizer Regions), and replication banding (BrdU incorporation in late replicating regions). Zebrafish chromosomes were obtained by the in vivo technique from adult fish. The diploid number of this species is 2n=50 and the NF=70 (NF= number of chromosome arms). Chromosomes were ordered approximately according to length. Given the similarity in size and morphology of most zebrafish chromosomes, only three chromosome pairs were unequivocally distinguished after Giemsa staining: the two metacentric pairs (6 and 11) and pair 1, the largest of the complement. Constitutive heterochromatin as demonstrated by C- banding was located at centromeric position of all chomosome pairs. After silver staining, Nucleolus Organizer Regions (NOR) appeared in telomeric position of the long arms of chromosomes 1, 2 and 8. Replication banding pattern allowed the identification of each chromosome pair.


Zebrafish Science Monitor Vol 3(5)
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