Sex chromosome evolution in fish. II. Second occurrence of an X1X2Y sex chromosome system in Gymnotiformes

被引：0
作者：
Lurdes F. de Almeida-Toledo
M. F. Z. Daniel-Silva
C. E. Lopes
Silvio de A. Toledo-Filho
机构：
[1] USP,Departamento de Biologia, Instituto de Biociências
来源：
Chromosome Research | 2000年 / 8卷
关键词：
gymnotid; heterochromatin; sex chromosomes; telomere;
D O I：
暂无
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学科分类号：
摘要：
A multiple sex chromosome system of the X1X1X2X2:X1X2Y type is reported to occur in the fish species Brachyhypopomus pinnicaudatus (Gymnotiformes, Hypopomidae), being the second occurrence of this sex chromosome system in Gymnotiformes and the fifth among Neotropical freshwater fish. The possible origin of this system was hypothesized to be a centric fusion, which occurred in an ancestral form, of two medium-sized acrocentrics, giving origin to the metacentric neo-Y. Heterochromatic DAPI-positive regions were visualized in the pericentromeric region of all the chromosomes, including the Y-chromosome. In-situ hybridization with (TTAGGG)n (all-human-telomeres probe) did not detect any telomeric interstitial regions (ITS), indicating a possible loss of terminal segments of the chromosomes involved in the neo-Y formation.
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页码：335 / 340
页数：5
相关论文
共 44 条
[1]  
Almeida-Toledo LF(1984)Complex sex chromosome system in Genetica 64 165-169
[2]  
Foresti F(1985) sp. (Pisces, Gymnotiformes) Genetica 66 85-88
[3]  
Toledo-Filho SA(1988)Spontaneous triploidy and NOR activity in Cytogenet Cell Genet 48 117-120
[4]  
Almeida-Toledo LF(1983) sp. (Pisces, Sternopygidae) from the Amazon basin Cytologia 48 1-12
[5]  
Foresti F(1997)BrdU replication patterns demonstrating chromosome homeologies in two fish species, genus Chromosome Res 5 493-499
[6]  
Toledo-Filho SA(1990)Multiple sex chromosomes in the genus Rev Brasil Genet 13 755-756
[7]  
Almeida-Toledo LF(1993) (Pisces, Erythrinidae) Rev Brasil Genet 16 585-600
[8]  
Viegas-Pequignot E(1992)The X1X2Y sex chromosome system in the fish Rev Brasil Genet 15 369-383
[9]  
Foresti F(1980). I. G-, C and chromosome replication banding Experientia 36 1014-1015
[10]  
Toledo-Filho SA(1980)Karyotypic diversification in Caryologia 33 83-91
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