Pawel Woznicki

Chromosome polymorphism in Salmo trutta morpha lacustris from Poland, Wdzydze Lake population: Variation in the short arm length of chromosome eleven

Abstract: A population of Salmo trutta m. lacustris from Lake Wdzydze was karyotyped using C-banding and fluorochrome staining techniques. The chromosome number was 2n = 80, and the chromosome arm number (NF) was 100-102. Variation in the size of the short arm of chromosome pair eleven was observed: the presence of heterochromatin on this arm was confirmed by C-banding and DAPI staining. Chromomycin A3 and silver stainings revealed the presence of nucleolar organizer region (NOR) on this arm. Additional CMA3-positive regions were observed on two acrocentric chromosomes. The polymorphism of chromosome pair eleven observed in Salmo trutta m. lacustris probably resulted from deletions or multiplications of heterochromatin connected to NOR. The karyotype and observed polymorphism of the NOR-bearing chromosome pair was the same as observed in other ecological forms of Salmo trutta.

Chromosome number and erythrocyte nuclei length in triploid brook trout (Salvelinus fontinalis)

Abstract The chromosome preparation and erythrocyte nuclei measurement were used to determine the ploidy in brook trout (Salvelinus fontinalis). The results show that the increase of chromosome number is correlated to increase of erythrocyte major axis.

Ploidy Level Determination in Genetically Manipulated Northern Pike Based on the Number of Active Nucleoli per Cell

Abstract Silver-staining of cell preparations followed by counting of the mean number of active nucleoli per cell enabled determination of the ploidy level in genetically manipulated northern pike Esox lucius. Haploid pike resulted from activation of eggs with sperm irradiated with ultraviolet light, and triploid specimens were obtained by applying high-temperature shock. Cells of haploid individuals had one (almost 100% of cells examined) or, sporadically, two nucleoli. Depending on the specimen, mean number of nucleoli per nucleus ranged from 1.0 to 1.06. In diploid fish, the mean number of active nucleoli per cell ranged from 1.58 to 1.81. In triploids, the mean ranged from 2.08 to 2.46. Positive identification of ploidy level in northern pike required examination of up to 40 cells per individual, as determined by the regression analysis. The method required a very small amount of any kind of tissue, enabling determination of ploidy level in juvenile fish without sacrificing them.

Chromosome number and erythrocyte nuclei length in triploid Siberian sturgeon Acipenser baeri Brandt

Abstract The chromosome preparation and erythrocyte nuclei measurements were used to determine the ploidy in Siberian sturgeon (Acipenser baeri Brandt): normal and after heat shock. The results show that the increase of chromosome number is highly correlated to increase of erythrocytes major axis.

Cytogenetic Characterization of Sea Trout (Salmo trutta) from Poland

Cytogenetic analysis of two local populations of sea trout (Salmo trutta) revealed a diploid chromosome number (2n) of 80 and a diploid chromosome arm number (NF) of 102. Two heteromorphic chromosome pairs were identified, based on Cbanding and DAPIand CMA3-staining: NOR-bearing pair 11 and metacentric pair 6. The study was designed to search for chromosome markers enabling separation of fish from one of the Pomeranian rivers (Slupia River) compared to those from the Vistula River. Frequencies of the heteromorphic chromosome pairs identified genetic differences between the two groups.

Heterochromatin and NOR location in northern pike (Esox lucius)

Abstact: Heterochromatin and the location of nucleolar organizer regions (NOR) were analyzed in northern pike (Esox lucius). The degree to which heterochromatin is present and its location are indicators of reorganization in karyotypes. Karyotypic analysis along with the use of conventional banding techniques and fluorochromes showed that the standard karyotypes was 2n = 50 chromosomes, with 50 chromosome arms (NF). NOR showed C- and CMA3-positive staining and were localized near the centromere of chromosome pair No. 11. Sequential staining using C-banding and DAPI techniques showed bright dots in the same region where NOR were localized.¶No sex heterochromosomes were recognizable on the basis of the staining techniques applied.

Chromosome variability in European vendace (Coregonus albula L.) from Poland

SUMMARYA population of European vendace, Coregonus albula from Lake Ukiel, Olsztyn District, Poland, has been karyotyped using conventional staining and banding techniques. Diploid chromosome number was 80 (NF = 96). The chromosome set consisted of 7 pairs of metacentric, 1 pair of submetacentric, 2 pairs of subtelocentric and 30 pairs of acrocentric chromosomes, gradually decreasing in size. Variation in size of one arm of second and fifth chromosome pair was observed. The presence of constitutive heterochromatin on these arms was confirmed by C-banding. The polymorphism of metacentric pairs observed in European vendace was probably due to deletion or to an involvement of heterochromatic arm in an unequal crossover. Examined fish possessed from 0 to 2 minute supernumerary chromosomes which were entirely heterochromatic, as was revealed by C-banding. The number and locations of active nucleolar organizer region (NOR) were demonstrated.