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Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2014-02-26T17:17:59Z No. of bitstreams: 1 WOS000189122200011.pdf: 97266 bytes, checksum: e88a57c05077111cae37480f320ca6ac (MD5) Made available in DSpace on 2014-02-26T17:17:59Z (GMT). No. of bitstreams: 1 WOS000189122200011.pdf: 97266 bytes, checksum: e88a57c05077111cae37480f320ca6ac (MD5) Previous issue date: 2003-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:51:27Z No. of bitstreams: 1 WOS000189122200011.pdf: 97266 bytes, checksum: e88a57c05077111cae37480f320ca6ac (MD5) Made available in DSpace on 2014-05-20T13:51:27Z (GMT). No. of bitstreams: 1 WOS000189122200011.pdf: 97266 bytes, checksum: e88a57c05077111cae37480f320ca6ac (MD5) Previous issue date: 2003-01-01 Univ Estadual Paulista, Inst Biociencias, Dept Morfol, BR-18618000 Botucatu, SP, Brazil Univ Estadual Paulista, Inst Biociencias, Dept Morfol, BR-18618000 Botucatu, SP, Brazil

Made available in DSpace on 2022-04-28T19:55:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-12-01 An early stage of sex chromosome differentiation is reported to occur in the electric eel Eigenmannia virescens (Pisces, Sternopygidae) from populations of two tributaries of the Paraná river system (Brazil). Cytogenetic studies carried out in the two populations showed that the Mogi-Guaçu population is characterized by 2n = 38 chromosomes and undifferentiated sex chromosomes and the Tietê population presents 2n = 38 both for males and females and an XX:XY sex chromosome system. The X-chromosome is acrocentric, easily recognized by the presence of a conspicuous heterochromatin block in its distal portion; the Y-chromosome is probably one of the medium sized acrocentrics present in the male karyotype. BrdU induced R-bands of the two populations did not reveal any difference in the euchromatic regions of the chromosomes. AluI and HaeIII restriction enzyme digestion patterns and chromomycin A3 staining of the X-chromosome are presented. The possible role of heterochromatinization in the evolution of sex chromosomes in fish is discussed. Copyright © 2002 S. Karger AG, Basel. Departamento de Biologia Instituto de Biociências USP, São Paulo Departamento de Morfologia Instituto de Biociências UNESP, Botucatu U 383 INSERM Hôpital Necker-Enfants Malades, Paris Departamento de Biologia Instituto de Biociências Universidade de São Paulo, Caixa Postal 11.461, 05422-970 São Paulo, SP Departamento de Morfologia Instituto de Biociências UNESP, Botucatu

Made available in DSpace on 2022-04-28T19:54:49Z (GMT). No. of bitstreams: 0 Previous issue date: 1998-12-01 The distribution of 5-methylcytosine (5-MeC) was investigated in fish chromosomes by indirect immunofluorescence using a highly specific 5-MeC monoclonal antibody. Diploid and artificially produced triploid specimens of the pacu fish, Piaractus mesopotamicus, were analyzed. The strong immunofluorescent signals were coincident with the heterochromatic regions of both diploids and triploids in a pattern that matched the C-banding pattern. In the euchromatin, heterogeneous labeling was observed along the chromatids. The weakness of this labeling hindered comparison of the fluorescence labeling of homologous chromosomes from diploid and triploid individuals. However, no striking differences were observed. The possibility that the euchromatin labeling by the 5-MeC antibody is related to the occurrence of mildly repetitive sequences in the genome of Piaractus is discussed. Departamento de Biologia Instituto de Biociências Universidade de São Paulo, São Paulo U 383 INSERM Hôpital Necker-Enfants Malades, Paris Departamento de Morfologia Instituto de Biociências UNESP, Botucatu Institut Pasteur CNRS, Lyon Departamento de Biologia Instituto de Biociências USP, Calxa Postal 11.461, 05422-970 São Paulo, SP Departamento de Morfologia Instituto de Biociências UNESP, Botucatu

Made available in DSpace on 2022-04-29T08:43:11Z (GMT). No. of bitstreams: 0 Previous issue date: 1997-12-01 The mitotic chromosomes, nucleolus organizer regions (NORs), C-banding pattern and nuclear DNA content of Mastacembelus armatus were studied. The karyotype (2n = 48; 10m + 6sm + 4st + 28a) was characterized by the presence of one chromosome pair with NORs and a small quantity of heterochromatin. The DNA content observed in erythrocyte nuclei of M. armatus was 1.39 ± 0.08 pg. Comparison of this karyotype with those of other Synbranchiformes revealed a strong similarity, suggesting that small chromosome rearrangements may have been maintained during its evolutionary history. Departamento de Morfologia Instituto de Biociências Campus de Botucatu, 18618-000, Botucatu, SP Faculdade de Farmácia Universidade de Marília, Marília, SP Museu de Zoologia Universidade de São Paulo, São Paulo, SP

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2014-02-26T17:07:49Z No. of bitstreams: 0 Made available in DSpace on 2014-02-26T17:07:49Z (GMT). No. of bitstreams: 0 Previous issue date: 1996-10-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:26:35Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T15:26:35Z (GMT). No. of bitstreams: 0 Previous issue date: 1996-10-01 Genetic analyses of sex determination have identified sex chromosomes in many teleost fish species. However, there are several cases for which sex ratios do not fit perfectly with the expectations of heterogametic systems, suggesting the influence of either minor sex determining genes or environmental influences on the process of sex differentiation. The frequent absence of sex chromosome markers makes the identification of minor sex-determining genes very difficult. It is easier to test first the hypothesis of environmental sex determination (ESD) by studying the temperature effect, since temperature-dependent sex determination has been demonstrated to occur in several vertebrate groups including 1 fish species. To contribute to a better understanding of fish sex determination, we have tested the effects of high temperatures on sex ratios of Oreochromis niloticus, and have attempted to isolate sex chromosome molecular markers in Leporinus elongatus. Treatments of O. niloticus fry at 36 degrees C applied for 10 days and more, and starting 1 week after fertilization markedly increased the proportion of males, and progeny-testing these males confirmed that some of them are sex-reversed genetic females. Two non-coding sequences of L. elongatus Z and W chromosomes were cloned by genomic subtraction. They cross-hybridized with the genome of a close species without providing sex-specific patterns. A collection of L. elongates individuals was subjected to gonadal and chromosomal sexing, and DNA hybridization with both sequences. These analyses revealed 3 individuals having atypical W chromosomes. Interestingly, 2 of these were males having a ZW karyotype. We assume that these atypical sex chromosome arise by exchanges between Z and W chromosomes, and that a transition between female and male heterogamety is underway in this species. INRA,LAB GENET POISSONS,F-78352 JOUY EN JOSAS,FRANCE CIRAD,EMVT,GRP AQUACULTURE TROP & MEDITERRANEENNE,F-34033 MONTPELLIER 1,FRANCE INRA,PHYSIOL POISSONS LAB,F-35042 RENNES,FRANCE UNIV ESTADUAL PAULISTA,DEPT MORFOL,BR-18618000 BOTUCATU,SP,BRAZIL Departamento de Morfologia, Botucatu, UNESP

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:17:59Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:28:18Z : No. of bitstreams: 1 2-s2.0-0029085472.pdf: 2511037 bytes, checksum: 7ace77fc8d3bf0d1aeb01dabd19f59f1 (MD5) Made available in DSpace on 2014-05-27T11:17:59Z (GMT). No. of bitstreams: 0 Previous issue date: 1995-01-01 Cytogenetic studies of three species of the subfamily Glandulocaudinae showed that Mimagoniates microlepis presents 2n = 52 chromosomes (6M + 20SM + 18ST + 8A), Mimagoniates lateralis presents 2n = 52 chromosomes (6M + 20SM + 16ST + 10A) and Glandalocauda melanogenys presents 2n = 52 chromosomes (4M + 12SM + 22ST + 14A). The number of NOR-bearing chromosome pairs ranged from two to four. Differences in number and position of NORs at the species and population levels were detected, suggesting that several chromosome rearrangements occurred in the evolutionary process of this group. Some aspects related to the chromosome evolution of the Glandulocaudinae are discussed. Departamento de Morfologia IB UNESP, 18618-000 Botucatu, SP Departamento de Morfologia IB UNESP, 18618-000 Botucatu, SP

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2014-02-26T17:05:24Z No. of bitstreams: 1 WOSA1993LJ96500020.pdf: 2564720 bytes, checksum: ce3ab4e830d7d387a8b6fee681f12a09 (MD5) Made available in DSpace on 2014-02-26T17:05:24Z (GMT). No. of bitstreams: 1 WOSA1993LJ96500020.pdf: 2564720 bytes, checksum: ce3ab4e830d7d387a8b6fee681f12a09 (MD5) Previous issue date: 1993-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:24:58Z No. of bitstreams: 1 WOSA1993LJ96500020.pdf: 2564720 bytes, checksum: ce3ab4e830d7d387a8b6fee681f12a09 (MD5) Made available in DSpace on 2014-05-20T15:24:58Z (GMT). No. of bitstreams: 1 WOSA1993LJ96500020.pdf: 2564720 bytes, checksum: ce3ab4e830d7d387a8b6fee681f12a09 (MD5) Previous issue date: 1993-06-01 In order to develop an efficient and low-cost technique for obtaining bird chromosome preparations, and to adapt the cytogenetic process of bird sexing for general use at zoos and breeding farms with the technical support of cytogenetics laboratories, we tested variants of the technique described by Giannoni et al. (Genet. Sel. Evol. 23: 123-125, 1991), based on the utilization of cellular material from growing feather pulp cultured in complete medium for six hours. Hanks' saline solution gave satisfactory performance as a substitute for complete medium, with no need to use PHA, serum of collagenase, when utilized in material obtained from feather pulp of Amazona amazonica (Psittacidae). UNESP,FCAVJ,DEPT MELHORAMENTO GENET ANIMAL,BR-14870 JABOTICABAL,SP,BRAZIL UNESP,FCAVJ,DEPT MELHORAMENTO GENET ANIMAL,BR-14870 JABOTICABAL,SP,BRAZIL

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2014-02-26T17:05:35Z No. of bitstreams: 1 WOSA1993MC77000006.pdf: 8556167 bytes, checksum: 1d950c9a4d83997afed16f8279880495 (MD5) Made available in DSpace on 2014-02-26T17:05:35Z (GMT). No. of bitstreams: 1 WOSA1993MC77000006.pdf: 8556167 bytes, checksum: 1d950c9a4d83997afed16f8279880495 (MD5) Previous issue date: 1993-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:27:47Z No. of bitstreams: 1 WOSA1993MC77000006.pdf: 8556167 bytes, checksum: 1d950c9a4d83997afed16f8279880495 (MD5) Made available in DSpace on 2014-05-20T15:27:47Z (GMT). No. of bitstreams: 1 WOSA1993MC77000006.pdf: 8556167 bytes, checksum: 1d950c9a4d83997afed16f8279880495 (MD5) Previous issue date: 1993-09-01 Four fish species of the family Pimelodidae were analyzed. Bergiaria westermani and two different Pimelodus species have the same diploid chromosome number (2n - 56). Despite some differences in chromosome structure, these species are highly similar in karyotype and differ from Pimelodella sp., which presents a reduction in chromosome number to 2n = 46. The data confirm the extensive chromosome variability existing in this family, characterized by intraindividual and/or population polymorphisms of a structural nature which may or may not be sexlinked, and by the presence of supernumerary chromosomes. UNIV ESTADUAL PAULISTA JULIO MESQUITA FILHO,INST BIOCIENCIAS,DEPT MORFOL,BR-18618 BOTUCATU,SP,BRAZIL UNIV ESTADUAL PAULISTA JULIO MESQUITA FILHO,INST BIOCIENCIAS,DEPT MORFOL,BR-18618 BOTUCATU,SP,BRAZIL

Made available in DSpace on 2022-04-28T18:54:03Z (GMT). No. of bitstreams: 0 Previous issue date: 1993-01-01 Depto. de Melhoramento Gen. Animal FCAVJ/UNESP, 14870-000 Jaboticabal Depto. de Melhoramento Gen. Animal FCAVJ/UNESP, 14870-000 Jaboticabal