CHROMOSOME ANALYSIS OF SCHISTOSOMA RODHAINI (TREMATODA: SCHISTOSOMATIDAE)

The chromosome number of Schistosoma rodhaini Brumpt is 2n = 16, with apparent sexual dimorphism quantifiable in chromosome pair no. 2. A method for dissociating host tissue coupled with hypotonic treatment yields permanent mitotic chromosome spreads with very defined centromere regions. The karyotype of S. rodhaini is very similar to that of its sibling species, S. mansoni Sambon, except there is a pericentric inversion in the S. rodhaini nucleolar organizer chromosome pair, S. rodhaini does not have any satellited chromosomes, and S. rodhaini has slightly shorter short arms of the group I chromosomes than S. mansoni. This distinction of chromosomes of similar species of schistosomes will be important for field identification of parasites and in elucidating the evolution of the schistosomes.

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Structure and variability of nucleolar organizer regions in Parodontidae fish

Canadian Journal of Genetics and Cytology ◽

10.1139/g84-089 ◽

1984 ◽

Vol 26 (5) ◽

pp. 564-568 ◽

Cited By ~ 51

Author(s):

Orlando Moreira-Filho ◽

Luiz Antonio Carlos Bertollo ◽

Pedro Manoel Galetti Jr.

Keyword(s):

Chromosome Pair ◽

Constitutive Heterochromatin ◽

Nucleolar Organizer ◽

Nucleolar Organizer Regions ◽

Mitotic Chromosomes ◽

Homozygous Condition ◽

Nucleolar Organizing Regions ◽

Nucleolar Chromosome

Nucleolar organizer regions (NORs) were studied in mitotic chromosomes of four species of fish of family Parodontidae: Parodon tortuosus, Apareiodon affinis, Apareiodon ibitiensis, and Apareiodon piracicabae. All four species exhibited only a single nucleolar chromosome pair in their karyotypes. Intraspecific differences were observed in the size of these chromosomes; however, these were not very clear for A. affinis and A. piracicabae, Apareiodon piracicabae exhibited two clearly visible NORs in each of the nucleolar chromosomes, which was the only configuration practically found in this species. This trait therefore predominates in a homozygous condition in the population investigated. Regions of constitutive heterochromatin adjacent to the two NORs were detected. Possible mechanisms that may have originated the two NORs are discussed.Key words: nucleolar organizing regions, fish.

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Hypotonic treatment in visual and automatic chromosome analysis

Clinical Genetics ◽

10.1111/j.1399-0004.1982.tb01427.x ◽

2008 ◽

Vol 22 (3) ◽

pp. 150-150 ◽

Cited By ~ 2

Author(s):

J. Bullerdiek ◽

S. Bartnitzke

Keyword(s):

Chromosome Analysis ◽

Hypotonic Treatment

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Cytogenetical analyses in three fish species of the genus Pimelodus(Siluriformes: Pimelodidae) from rio São Francisco: considerations about the karyotypical evolution in the genus

Neotropical Ichthyology ◽

10.1590/s1679-62252005000200006 ◽

2005 ◽

Vol 3 (2) ◽

pp. 285-290 ◽

Cited By ~ 25

Author(s):

Caroline Garcia ◽

Orlando Moreira Filho

Keyword(s):

Chromosome Pair ◽

Chromosomal Rearrangements ◽

Nucleolar Organizer ◽

Differential Staining ◽

Nucleolar Organizer Regions ◽

C Banding ◽

Heteromorphic Sex Chromosomes ◽

Chromosomal Markers ◽

Staining Techniques ◽

Species Specific

Karyotypes and other chromosomal markers were investigated in three species of the catfish genus Pimelodus, namely P. fur, P. maculatus and Pimelodus sp., from municipality of Três Marias, Minas Gerais, Brazil, using differential staining techniques (C-banding, Silver nitrate and CMA3 staining). The diploid chromosome number was 2n = 56 in P. maculatus and Pimelodus sp., while in P. fur 2n = 54. The karyotype of P. fur consisted in 32M + 8SM + 6ST + 8A with fundamental number (NF) of 100, that of P. maculatus 32M + 12SM + 12A with NF = 112, and that of Pimelodus sp. had 32M + 12Sm + 6ST + 6A with NF = 106.The nucleolar organizer regions (NORs) in all three species were invariably detected in telomeres of longer arm of the 20th chromosome pair. These sites were also positive after CMA3 and C-banding. No heteromorphic sex chromosomes were detected and C-banding pattern was species specific. Inferences about the karyotype differentiation in Pimelodus and putative chromosomal rearrangements are hypohesized.

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Polytene and mitotic chromosome analysis in Ceratitis capitata (Diptera; Tephritidae)

Canadian Journal of Genetics and Cytology ◽

10.1139/g86-025 ◽

1986 ◽

Vol 28 (2) ◽

pp. 180-188 ◽

Cited By ~ 42

Author(s):

D. G. Bedo

Keyword(s):

X Chromosome ◽

Silver Staining ◽

Mitotic Chromosome ◽

Ceratitis Capitata ◽

Fat Body ◽

Polytene Chromosomes ◽

Chromosome Analysis ◽

Mitotic Chromosomes ◽

Chromosome Separation ◽

Ectopic Pairing

Polytene chromosomes were found in several larval and pupal tissues of the Medfly, Ceratitis capitata, during a search for chromosomes suitable for detailed cytological analysis. Well-banded highly polytene chromosomes, which could be adequately separated and spread, were found in trichogen cells of the spatulate superior orbital bristles of male pupae. These chromosomes proved suitable for full polytene analysis. Thoracic trichogen cells of both male and female pupae also contain useful polytene chromosomes, although they are considerably thinner and thus more difficult to analyze. Contrasting with those in pupal trichogen cells, the chromosomes in the salivary glands, Malphighian tubules, midgut, hindgut, and fat body of larvae and pupae were difficult to prepare because of high levels of ectopic pairing and chromosome fragmentation. In hindgut preparations partial separation of up to three chromosomes was achieved, but in all other tissues no useful chromosome separation was possible. In trichogen polytene cells, five banded chromosomes and a prominent heterochromatic network associated with a nucleolus are found. The mitotic chromosomes respond to C- and Q-banding and silver staining with considerable variation. This is especially so in the X chromosome, which displays an extensive array of bands following both Q-banding and silver staining. Comparison of Q-banded metaphase and polytene chromosomes demonstrates that the five autosomes are represented by conventional polytene chromosomes, while the sex chromosomes are contained in the heterochromatic net, most of which fluoresces strongly. This suggests that the Q-bands of the mitotic X chromosome are replicated to a greater extent than the nonfluorescent material in polytene cells. This investigation shows C. capitata to have excellent cytological material for both polytene and mitotic analysis.Key words: Ceratitis capitata, Medfly, chromosomes (polytene), banding (chromosome).

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

Genetics and Molecular Biology ◽

10.1590/s1415-47572000000300011 ◽

2000 ◽

Vol 23 (3) ◽

pp. 563-567 ◽

Cited By ~ 7

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.

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Studies of the X chromosome of Anopheles albimanus

Canadian Journal of Genetics and Cytology ◽

10.1139/g85-013 ◽

1985 ◽

Vol 27 (1) ◽

pp. 74-82

Author(s):

J. A. Seawright ◽

M. Q. Benedict ◽

S. Narang

Keyword(s):

X Chromosome ◽

Organizer Region ◽

Nucleolar Organizer Region ◽

Nucleolar Organizer ◽

Chromosome Analysis ◽

Anopheles Albimanus ◽

Eye Color ◽

Colour Mutant ◽

Translocation Breakpoints ◽

Radiation Induced

Snow (sn) is a recessive, eye color mutant that is phenotypically indistinguishable from the previously described mutant, white eye (we). The loci for these mutants are over 30 map units apart on the X chromosome. Analysis of salivary gland chromosomes of radiation-induced X-autosome translocations were used to define the positions of sn and we on the distal euchromatic portion of the long arm of the X chromosome. A recessive lethal trait (bubble head) was also mapped relative to we and sn, and the gene order on the long arm of the X chromosome is as follows: centromere – ? – snow – bubble head – white eye. Translocation breakpoints in the euchromatic portion of the X chromosome caused sterility or lethality in males hemizygous for the translocations, but breaks in the heterochromatin had no effect. Crossing-over was greatly reduced when translocation breakpoints were located in the euchromatic part of the X chromosome. The translocations were used to determine that the nucleolar organizer region is probably on the short arm of the X chromosome.Key words: Anopheles albimanus, eye colour mutant, X chromosome.

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First chromosome analysis of Thai pufferfish Pao cochinchinensis (Steindachner, 1866)

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d210949 ◽

2020 ◽

Vol 21 (9) ◽

Author(s):

MANACHAYA PISSAPARN ◽

SUMALEE PHIMPHAN ◽

PATCHARAPORN CHAIYASAN ◽

ALONGKLOD TANOAMTONG ◽

THOMAS LIEHR ◽

...

Keyword(s):

Organizer Region ◽

Nucleolar Organizer Region ◽

Molecular Cytogenetics ◽

Nucleolar Organizer ◽

Chromosome Analysis ◽

Chromosomal Evolution ◽

Giemsa Staining ◽

Heteromorphic Sex Chromosomes ◽

Almost All

Abstract. Pissaparn M, Phimphan S, Chaiyasan P, Tanoamtong A, Liehr T, Suwannapoom C, Reungsing M, Supiwong W. 2020. First chromosome analysis of Thai pufferfish Pao cochinchinensis (Steindachner, 1866). Biodiversitas 21: 4309-4316. Here first analysis of chromosomes and nucleolar organizer region (NOR) pattern in pufferfish Pao cochinchinensis (Steindachner, 1866) was undertaken. Chromosomal preparations were obtained from kidney of P. cochinchinensis from Chi River basin in Thailand. Chromosomal characteristics were analyzed by Giemsa staining, Ag-NOR banding as well as fluorescence in situ hybridization (FISH) using microsatellites d(CA)15 and d(CGG)10 probes. P. cochinchinensis had 2n = 40 with the fundamental number (NF) 74, both in male and female. The karyotype exhibited 12 metacentric (m), 10 submetacentric (sm), 12 acrocentric (a) and 6 telocentric (t) chromosomes. No differentiated heteromorphic sex chromosomes were observed. NORs were located on short arms adjacent to telomere of the metacentric chromosome pair 4, which coincide with signals of d(CGG)10 probe. FISH with d(CGG)10 sequences were also displayed at the telomeres of most other chromosomes, whereas d(CA)15 repeats highly accumulated throughout almost all entire chromosomes except for centromeric regions. The results of conventional Giemsa staining presented the differentiation even the same genus. The localization of NORs on one pair of chromosomes only is a common characteristic found in many fish groups as well as other vertebrates. Mapping of two distinct microsatellites demonstrated the remarkable chromosomal diversification that characterizes evolution in the genus Pao. Both, conventional and molecular cytogenetics are excellent tools to study, and better understand chromosomal evolution, as well as to uncover biodiversity among fishes.

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Report of Bradinopyga konkanensis Joshi & Sawant, 2020 (Insecta: Odonata) from Kerala, India

Journal of Threatened Taxa ◽

10.11609/jott.6484.13.8.19173-19176 ◽

2021 ◽

Vol 13 (8) ◽

pp. 19173-19176

Author(s):

Muhammed Haneef ◽

B. Raju Stiven Crasta ◽

A. Vivek Chandran

Keyword(s):

Similar Species ◽

Field Identification ◽

Dragonfly Species

The newly described dragonfly species, Bradinopyga konkanensis Joshi & Sawant 2020 (Insecta: Odonata), is reported from Kerala, 450 km away from its nearest record. Differences between closely similar species that co-occur in the region are tabulated for easy field identification of the species.

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Chromosomal characterization of cultured populations of Chilean coho salmon (Oncorhynchus kistuch)

Genetics and Molecular Biology ◽

10.1590/s1415-47571999000100008 ◽

1999 ◽

Vol 22 (1) ◽

pp. 33-38 ◽

Cited By ~ 1

Author(s):

Nelson Colihueque V.

Keyword(s):

Pericentric Inversion ◽

Chromosome Pair ◽

Secondary Constriction ◽

Coho Salmon ◽

Southern Chile ◽

Fish Farms ◽

Submetacentric Chromosome ◽

Chromosome Arm

Chromosomal characterization of coho salmon samples from three fish farms in southern Chile (Polcura, Castro and Coyhaique) was carried out in order to compare their chromosome constitutions. All populations had a 2n = 60; however, Polcura and Coyhaique had a different chromosome arm number (NF = 110; 40m + 10sm + 10st/t) than Castro (NF = 108; 40m + 8sm + 12st/t). Variation in NF was due to chromosome pair 25, which was submetacentric in Coyhaique and Polcura, but subtelocentric in Castro. In all karyotypes, a large submetacentric chromosome pair exhibited an interstitial secondary constriction in the short arm. The observed variability in chromosome arm number agrees with previous reports for O. kisutch, and in this particular case it seemed to be caused by a pericentric inversion of pair 25. Cultured populations of Chilean coho salmon are, therefore, likely to be cytogenetically variable.

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