PMID- 18041928
OWN - NLM
STAT- MEDLINE
DCOM- 20080320
LR  - 20071128
IS  - 1557-8542 (Electronic)
IS  - 1545-8547 (Linking)
VI  - 4
IP  - 2
DP  - 2007 Summer
TI  - Molecular cytogenetics of blind mexican tetra and comments on the karyotypic 
      characteristics of genus Astyanax (Teleostei, Characidae).
PG  - 103-11
AB  - Astyanax mexicanus is popularly known as the blind Mexican tetra or blind cave 
      tetra and has been extensively studied regarding various aspects of its biology 
      and genetics. Despite the identification of linkage maps of genes related to 
      quantitative trait loci by many recent studies, only its diploid number was known 
      from a cytogenetical point of view. With the purpose of providing a base for 
      comparative studies and for the elucidation of physical maps for the species, 
      cytogenetical studies were performed in a group of 10 blind specimens from 
      Mexico. All the individuals presented 2n = 50 chromosomes and a karyotypic 
      formula composed of 8M + 18SM + 12ST + 12A. A few specimens presented one or two 
      B microchromosomes of the acrocentric type. Although simple argyrophilic 
      nucleolar organizer regions (Ag-NORs) were evidenced, fluorescence in situ 
      hybridization (FISH) with an 18S rDNA probe evidenced eight sites, and six sites 
      were observed with a 5S rDNA probe. Little constitutive heterochromatin was 
      observed, mainly related with the Ag-NORs and located close to the centromeres, 
      including those from the B microchromosomes. A few pericentromeric 
      heterochromatin regions were mainly constituted by GC, including the one from the 
      Ag-NOR. Very subtle markings were observed by FISH with an As-51 satellite DNA 
      probe. The B microchromosome did not present ribosomal genes or satellite DNA. 
      Chromosomal aspects of the genus Astyanax are discussed.
FAU - Kavalco, Karine Frehner
AU  - Kavalco KF
AD  - Department of Genetics and Evolutionary Biology, University of Sao Paulo, Sao 
      Paulo, Brazil. kavalco@biociencia.org
FAU - De Almeida-Toledo, Lurdes Foresti
AU  - De Almeida-Toledo LF
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Zebrafish
JT  - Zebrafish
JID - 101225070
RN  - 0 (Antigens, Nuclear)
RN  - 0 (DNA, Satellite)
RN  - 0 (Nuclear Proteins)
RN  - 0 (RNA, Ribosomal, 18S)
RN  - 0 (RNA, Ribosomal, 5S)
RN  - 0 (nucleolar organizer region associated proteins)
RN  - 9007-49-2 (DNA)
SB  - IM
MH  - Animals
MH  - Antigens, Nuclear/genetics
MH  - Chromosomes/metabolism
MH  - Cytogenetic Analysis/veterinary
MH  - DNA/*analysis
MH  - DNA, Satellite/genetics
MH  - Fishes/*genetics
MH  - In Situ Hybridization, Fluorescence/veterinary
MH  - Karyotyping/veterinary
MH  - Mexico
MH  - Nuclear Proteins/genetics
MH  - RNA, Ribosomal, 18S/genetics
MH  - RNA, Ribosomal, 5S/genetics
EDAT- 2007/11/29 09:00
MHDA- 2008/03/21 09:00
CRDT- 2007/11/29 09:00
PHST- 2007/11/29 09:00 [pubmed]
PHST- 2008/03/21 09:00 [medline]
PHST- 2007/11/29 09:00 [entrez]
AID - 10.1089/zeb.2007.0504 [doi]
PST - ppublish
SO  - Zebrafish. 2007 Summer;4(2):103-11. doi: 10.1089/zeb.2007.0504.