Chromosomal NOR phenotypes in North American pikes and pickerels, genus Esox, with notes on the Umbridae (Euteleostei: Esocae)

1994 ◽  
Vol 72 (11) ◽  
pp. 1951-1956 ◽  
Author(s):  
P. Ráb ◽  
E. J. Crossman
Keyword(s):  
North American ◽  
Chromosome Pair ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Nucleolar Organizer ◽  
Pericentromeric Region ◽  
European Species ◽  
The North ◽  
Nor Phenotype ◽  
Umbra Krameri

A comparison was made of the localization of nucleolar organizer region (NOR) sites in the karyotypes of the North American pikes and pickerels Esox lucius, E. masquinongy, E. niger, and the two subspecies of E. americanus (Esocidae). NORs were located by silver staining or chromomycin A3 fluorescence. The study revealed that the position of chromosomal NORs in all Esox taxa examined was the same: the pericentromeric region of one middle-sized chromosome pair. The same NOR phenotype was found previously in a related European species, Umbra krameri (Umbridae), and in U. pygmaea, one of the two North American representatives of the genus. The NOR phenotype of the remaining North American species (U. limi) is different. It is hypothesized that this kind of NOR phenotype, shared by two phyletic lineages in the Esocae, represents an ancestral character for the members of that group.

scholarly journals Cytogenetics of the neotropical flesh fly Pattonela intermutans (Diptera, Sarcophagidae)

2000 ◽  
Vol 23 (3) ◽  
pp. 563-567 ◽  
Author(s):  
Patricia Pasquali Parise-Maltempi ◽  
Rita Maria Pereira Avancini
Keyword(s):  
Sex Chromosomes ◽  
Chromosome Pair ◽  
Sex Chromosome ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Nucleolar Organizer ◽  
Pericentromeric Region ◽  
Flesh Fly ◽  
Fish Technique

Pattonella intermutans has 2n = 12 chromosomes including three metacentric and two submetacentric pairs of autosomes and an XX/XY sex chromosome pair. The autosomes are characterized by the presence of a C band in the pericentromeric region while sex chromosomes are totally heterochromatic. The FISH technique showed a nucleolar organizer region (NOR) in autosome IV.

Cytogenetic studies in North American minnows (Cyprinidae). XXII. Chromosomal nucleolar organizer regions in the genus Pimephales

1991 ◽  
Vol 69 (11) ◽  
pp. 2826-2830 ◽  
Author(s):  
Yucheng Li ◽  
John R. Gold
Keyword(s):  
North American ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Nucleolar Organizer ◽  
Nucleolar Organizer Regions ◽  
Submetacentric Chromosome ◽  
The North ◽  
Extant Species ◽  
Previous Hypothesis ◽  
Chromosomal Data

Chromosomal nucleolar organizer region (NOR) phenotypes are documented for all four extant species in the North American cyprinid fish genus Pimephales. All four species (P. notatus, P. promelas, P. tenellus, and P. vigilax) possess 2n = 50 chromosomes and a pair of NOR-bearing chromosomes with the NOR situated terminally on the short arm of a medium-sized to large submetacentric chromosome (NOR phenotype C). Trypsin G-banding demonstrated that the C NOR chromosome in all four species is homologous. Two of the species (P. tenellus and P. promelas) also possess a C′ NOR chromosome, which is defined as an NOR situated terminally on the short arm of a large submetacentric chromosome that is also the largest chromosome in the complement. The C′ NOR chromosome occurs infrequently in P. promelas, being found in only 8% or so of all metaphases examined. Trypsin G-banding demonstrated that the C′ NOR chromosomes in the two Pimephales species are homologous to one another and to the C′ NOR chromosomes found in the cyprinid genus Cyprinella. A presumed derivative of the C′ NOR chromosome occurs in the monotypic cyprinid genus Opsopoeodus. The NOR chromosomal data support monophyly of the four extant species of Pimephales, and further suggest that the genus Pimephales belongs in a monophyletic assemblage with, among others, the cyprinid genera Cyprinella and Opsopoeodus. The data do not support the previous hypothesis that Pimephales is a basal clade outside of a larger assemblage of "Notropis"-like, shiners.

scholarly journals Comparative FISH analysis of Senna tora tandem repeats revealed insights into the chromosome dynamics in Senna

2021 ◽  
Vol 43 (3) ◽  
pp. 237-249 ◽  
Author(s):  
Thanh Dat Ta ◽  
Nomar Espinosa Waminal ◽  
Thi Hong Nguyen ◽  
Remnyl Joyce Pellerin ◽  
Hyun Hee Kim
Keyword(s):  
Tandem Repeats ◽  
Chromosomal Rearrangements ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Nucleolar Organizer ◽  
Pericentromeric Region ◽  
Its2 Sequence ◽  
Fish Analysis ◽  
Chromosomal Distribution ◽  
Chromosome Dynamics

Abstract Background DNA tandem repeats (TRs) are often abundant and occupy discrete regions in eukaryotic genomes. These TRs often cause or generate chromosomal rearrangements, which, in turn, drive chromosome evolution and speciation. Tracing the chromosomal distribution of TRs could therefore provide insights into the chromosome dynamics and speciation among closely related taxa. The basic chromosome number in the genus Senna is 2n = 28, but dysploid species like Senna tora have also been observed. Objective To understand the dynamics of these TRs and their impact on S. tora dysploidization. Methods We performed a comparative fluorescence in situ hybridization (FISH) analysis among nine closely related Senna species and compared the chromosomal distribution of these repeats from a cytotaxonomic perspective by using the ITS1-5.8S-ITS2 sequence to infer phylogenetic relationships. Results Of the nine S. tora TRs, two did not show any FISH signal whereas seven TRs showed similar and contrasting patterns to other Senna species. StoTR01_86, which was localized in the pericentromeric regions in all S. tora, but not at the nucleolar organizer region (NOR) site, was colocalized at the NOR site in all species except in S. siamea. StoTR02_7_tel was mostly localized at chromosome termini, but some species had an interstitial telomeric repeat in a few chromosomes. StoTR05_180 was distributed in the subtelomeric region in most species and was highly amplified in the pericentromeric region in some species. StoTR06_159 was either absent or colocalized in the NOR site in some species, and StoIGS_463, which was localized at the NOR site in S. tora, was either absent or localized at the subtelomeric or pericentromeric regions in other species. Conclusions These data suggest that TRs play important roles in S. tora dysploidy and suggest the involvement of 45S rDNA intergenic spacers in “carrying” repeats during genome reshuffling.

Karyotype, meiotic behavior and pollen features of Senna occidentalis

Biologia ◽  
2010 ◽  
Vol 65 (5) ◽  
Author(s):  
Kátia Ferreira ◽  
Giovana Torres ◽  
Saulo Sousa ◽  
Aparecida Santos
Keyword(s):  
Chromosome Pair ◽  
Pollen Morphology ◽  
Secondary Constriction ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Pollen Grains ◽  
Nucleolar Organizer ◽  
Mitotic Metaphase ◽  
Meiotic Behavior ◽  
Mitotic Metaphase Chromosome

AbstractMeiotic behavior, pollen morphology, interphasic nucleus pattern and karyotype description for Senna occidentalis (Caesalpinioideae — Fabaceae) are presented. The species had non-reticulate interphasic nucleus and homogeneous chromosome condensing with minute distal late-condensing portions in prometaphase. In mitotic metaphase, chromosome number was 2n = 28 (9 m + 5 sm), with secondary constriction in one chromosome pair. Detection of four nucleoli indicated existence of two chromosome pairs bearing Nucleolar Organizer Region (NOR). Meiotic behavior was regular, with high meiotic index (95%). Pollen grains, classified as polar/spheroidal, presented 90% viability.

scholarly journals Evolutionary cytogenetics of the Hoplias lacerdae, Miranda Ribeiro, 1908 group: a particular pathway concerning the other Erythrinidae fish

2007 ◽  
Vol 67 (4 suppl) ◽  
pp. 897-903 ◽  
Author(s):  
S. Morelli ◽  
MR. Vicari ◽  
LAC. Bertollo
Keyword(s):  
Silver Staining ◽  
Chromosome Pair ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Nucleolar Organizer ◽  
The Other ◽  
Rdna Sites ◽  
Group A ◽  
Morphologic Data ◽  
Erythrinidae Fish

The taxonomy/systematics of the Erythrinidae fish is still imprecise, with several doubts on their relationships. Karyotypes and chromosomal characteristics of some species of the Hoplias lacerdae group (Erythrinidae), from different Brazilian hydrographic basins and pisciculture stations, were analyzed in the present study, using conventional Giemsa staining, C-banding, silver staining, Mithramycin and Distamycin/DAPI fluorochromes, and fluorescent in situ hybridization (FISH). A diploid chromosome number of 2n = 50 and karyotypes composed of meta- and submetacentric chromosomes without sex-related differences were found. Only one active NOR (Nucleolar Organizer Region) site was found, which was identified by silver staining (Ag-NOR) and FISH, located on the chromosome pair 11, although additional 45S rDNA sites were also mapped on other chromosome pairs only by FISH. The Ag-NOR of the chromosome pair 11 was found to be GC-rich, appearing positive after Mithramycin staining. Mithramycin-positive/DAPI-negative sites were also observed in the centromeric/pericentomeric regions of the chromosome pairs 4, 6, 15, and 19, which have also affinity to silver nitrate. However, these four sites were not detected by FISH with the rDNA probe, indicating to be only argentophilic GC-rich heterochromatic regions. Chromosome data show that the karyotype evolution in Hoplias lacerdae group is relatively conserved and follows a particular pathway concerning the other Erythrinidae fishes, such as Hoplias malabaricus, Hoplerythrinus unitaeniatus, and Erythrinus erythrinus, in which polytypic karyotypes are found. Thus, the H. lacerdae group shows chromosome features that are not closely related to those of the congeneric H. malabaricus group. These finds, together with genetic and morphologic data, are important tools to be considered in a major revision of the Erythrinidae family, as well as for conservation programs.

Inheritance of a chromosomal polymorphism in odd-year pink salmon from southeastern Alaska

Genome ◽  
1999 ◽  
Vol 42 (5) ◽  
pp. 816-820 ◽  
Author(s):  
R B Phillips ◽  
M P Matsuoka ◽  
W W Smoker ◽  
A J Gharrett
Keyword(s):  
Chromosome Pair ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Pink Salmon ◽  
Chromosomal Polymorphism ◽  
Nucleolar Organizer ◽  
Oncorhynchus Gorbuscha ◽  
Submetacentric Chromosome ◽  
South Central ◽  
Significant Difference

In previous work we found a high frequency of heterozygotes for a fission translocation involving the seventh chromosome pair in odd-year populations of pink salmon (Oncorhynchus gorbuscha) sampled from Washington State to south central Alaska. The populations from southeastern Alaska and northern British Columbia had high frequencies of heterozygotes for a second rearrangement of this same chromosome pair. In these fish one fission product, the larger acrocentric chromosome bearing the nucleolar organizer region (NOR), has undergone an inversion to produce a submetacentric chromosome. In this paper, we present inheritance data on pink salmon from the Gastineau hatchery stock in Juneau, Alaska, where individuals with the two rearrangements are found. Although most of the fish were either homozygous for the normal cytotype or heterozygous for the inversion cytotype, a few individuals heterozygous for the fission cytotype were found. Ten males and ten females were karyotyped, and crosses were set up in all combinations. Individuals with both rearrangements were found in crosses between the two types of heterozygotes, and the ratios of cytotypes in the progeny did not deviate significantly from the expected values. No significant difference in viability of offspring from crosses between individuals with different cytotypes was found up to the age of hatching.Key words: salmon, chromosomal polymorphism, translocation, inversion, cytotype.

scholarly journals The genomic structure of a human chromosome 22 nucleolar organizer region determined by TAR cloning

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jung-Hyun Kim ◽  
Vladimir N. Noskov ◽  
Aleksey Y. Ogurtsov ◽  
Ramaiah Nagaraja ◽  
Nikolai Petrov ◽  
...  
Keyword(s):  
Genomic Structure ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Nucleolar Organizer ◽  
Chromosome 21 ◽  
Reference Sequence ◽  
Chromosome 22 ◽  
Rdna Variation ◽  
High Level ◽  
Tar Cloning

AbstractThe rDNA clusters and flanking sequences on human chromosomes 13, 14, 15, 21 and 22 represent large gaps in the current genomic assembly. The organization and the degree of divergence of the human rDNA units within an individual nucleolar organizer region (NOR) are only partially known. To address this lacuna, we previously applied transformation-associated recombination (TAR) cloning to isolate individual rDNA units from chromosome 21. That approach revealed an unexpectedly high level of heterogeneity in human rDNA, raising the possibility of corresponding variations in ribosome dynamics. We have now applied the same strategy to analyze an entire rDNA array end-to-end from a copy of chromosome 22. Sequencing of TAR isolates provided the entire NOR sequence, including proximal and distal junctions that may be involved in nucleolar function. Comparison of the newly sequenced rDNAs to reference sequence for chromosomes 22 and 21 revealed variants that are shared in human rDNA in individuals from different ethnic groups, many of them at high frequency. Analysis infers comparable intra- and inter-individual divergence of rDNA units on the same and different chromosomes, supporting the concerted evolution of rDNA units. The results provide a route to investigate further the role of rDNA variation in nucleolar formation and in the empirical associations of nucleoli with pathology.

Nucleolar organizer region staining patterns in paraffin-embedded tissue cells from human skin cancers

2005 ◽  
Vol 32 (5) ◽  
pp. 323-328 ◽  
Author(s):  
Rosana F. Romao-Correa ◽  
Durvanei A. Maria ◽  
Mithitaka Soma ◽  
Mirian N. Sotto ◽  
Jose Antonio Sanches ◽  
...  
Keyword(s):  
Human Skin ◽  
Organizer Region ◽  
Nucleolar Organizer Region ◽  
Nucleolar Organizer ◽  
Skin Cancers ◽  
Tissue Cells
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