| Popis: |
The chromosomal characteristics, locations and variations of the heterochromatin were studied in the European huchen (Hucho hucho, Linnaeus, 1758) karyotype using conventional C- banding, endonuclease digestion banding, silver nitrate (AgNO3), chromomycin A3 (CMA3) and DAPI staining techniques. The karyotype consists of 82 chromosomes: 13 pairs of metacentric chromosomes, 2 pairs of submetacentric chromosomes and 26 pairs of subtelo-acrocentric chromosomes (NF = 112). Original data on the chromosomal distribution of segments resistant to Alu I, Dde I and Mbo I restriction endonucleases and identification of the C-banded heterochromatin presented here have been used to characterize the huchen karyotype. On the basis of the banding patterns provided in the course of restriction enzyme digestion, AgNO3/CMA3 staining and C-banding we distinguished twelve types of heterochromatin grouped in four areas of the European huchen chromosomes. One pair of NOR-bearing chromosomes was found to be polymorphic in size and displayed two distinct forms. A combination of various staining techniques provided original data concerning heterochromatin distribution and heterogeneity in the European huchen which enabled better karyotypic definition of this fish species. |
