PMID- 17705059
OWN - NLM
STAT- MEDLINE
DCOM- 20080624
LR  - 20080331
IS  - 0016-6707 (Print)
IS  - 0016-6707 (Linking)
VI  - 133
IP  - 1
DP  - 2008 May
TI  - Molecular cytogenetics and characterization of a ZZ/ZW sex chromosome system in 
      Triportheus nematurus (Characiformes, Characidae).
PG  - 85-91
AB  - Chromosomes of Triportheus nematurus, a fish species from family Characidae, were 
      analyzed in order to establish the conventional karyotype, location of C-band 
      positive heterochromatin, Ag-NORs, GC- and AT-rich sites, and mapping of 18S and 
      5S rDNA with fluorescence in situ hybridization (FISH). The diploid number found 
      was 2n = 52 chromosomes in both males and females. However, the females presented 
      a pair of differentiated heteromorphic chromosomes, characterizing a ZZ/ZW sex 
      chromosome system. The Z chromosome was metacentric and the largest one in the 
      karyotype, bearing C-positive heterochromatin at pericentromeric and telomeric 
      regions. The W chromosome was middle-sized submetacentric, appearing mostly 
      heterochromatic after C-banding and presenting heterogeneous heterochromatin 
      composed of GC- and AT-rich regions revealed by fluorochrome staining. Ag-NORs 
      were also GC-rich and surrounded by heterochromatic regions, being located at the 
      secondary constriction on the short arms of the second chromosome pair, in 
      agreement with 18S rDNA sites detected with FISH. The 18S and 5S rDNA were 
      aligned in tandem, representing an uncommon situation in fishes. The results 
      obtained reinforce the basal condition of the ZZ/ZW sex system in the genus 
      Triportheus, probably arisen prior to speciation in the group.
FAU - Diniz, Debora
AU  - Diniz D
AD  - Departamento de Genetica e Evolucao, Universidade Federal de Sao Carlos, Sao 
      Carlos, SP 13565-905, Brazil. debdiniz18@yahoo.com.br
FAU - Moreira-Filho, Orlando
AU  - Moreira-Filho O
FAU - Bertollo, Luiz Antonio Carlos
AU  - Bertollo LA
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20070820
PL  - Netherlands
TA  - Genetica
JT  - Genetica
JID - 0370740
RN  - 0 (Heterochromatin)
SB  - IM
MH  - Animals
MH  - Cytogenetic Analysis/*methods
MH  - Female
MH  - Fishes/*genetics
MH  - Heterochromatin/genetics
MH  - In Situ Hybridization, Fluorescence
MH  - Male
MH  - Sex Chromosomes/*genetics
EDAT- 2007/08/21 09:00
MHDA- 2008/06/25 09:00
CRDT- 2007/08/21 09:00
PHST- 2007/02/06 00:00 [received]
PHST- 2007/07/26 00:00 [accepted]
PHST- 2007/08/21 09:00 [pubmed]
PHST- 2008/06/25 09:00 [medline]
PHST- 2007/08/21 09:00 [entrez]
AID - 10.1007/s10709-007-9187-9 [doi]
PST - ppublish
SO  - Genetica. 2008 May;133(1):85-91. doi: 10.1007/s10709-007-9187-9. Epub 2007 Aug 
      20.