PMID- 12698003
OWN - NLM
STAT- MEDLINE
DCOM- 20030513
LR  - 20171101
IS  - 1424-8581 (Print)
IS  - 1424-8581 (Linking)
VI  - 98
IP  - 2-3
DP  - 2002
TI  - Chromosomal characteristics of ribosomal DNA in two extant species of North 
      American mudminnows Umbra pygmaea and U. limi (Euteleostei: Umbridae).
PG  - 194-8
AB  - The locations and chromosomal characteristics of ribosomal DNA (rDNA) sites in 
      the karyotypes of two extant North American species of mudminnows, Umbra pygmaea 
      and U. limi (2n = 22, NF = 44), were analyzed sequentially by conventional Giemsa 
      staining, Ag staining, CMA(3) fluorescence and fluorescence in situ hybridization 
      (FISH). The nucleolar organizer regions (NORs) were located in the fourth 
      chromosomal pair in both species (pericentromeric region in U. pygmaea and 
      subtelomeric in U. LIMI). These sites were strongly CMA(3)-positive suggesting 
      that the rDNA sites in these species are associated with GC-rich DNA. FISH with a 
      rDNA probe gave consistently positive signals in the same regions detected by 
      Ag-staining and CMA(3)-fluorescence. However, both species also had additional 
      CMA(3)-positive/Ag-negative heterochromatic blocks at pericentrometric regions of 
      several chromosomal pairs (three in U. pygmaea and five in U. limi). FISH 
      revealed additional rDNA clusters in both species. It is hypothesized that a 
      paracentric inversion of the chromosome arm carrying the NORs might be one of the 
      rearrangements differentiating the karyotypes of two North American species. The 
      presence of additional rDNA sites is indicative of more complex rearrangements. 
      The pericentromeric NOR phenotype of Umbra pygmaea is similar to that seen in U. 
      krameri and in the distantly related genus Esox.
CI  - Copyright 2002 S. Karger AG, Basel
FAU - Rab, P
AU  - Rab P
AD  - Laboratory of Fish Genetics, Institute of Animal Physiology and Genetics, Czech 
      Academy of Sciences, Libechov, Czech Republic. rab@iapg.cas.cz
FAU - Crossman, E J
AU  - Crossman EJ
FAU - Reed, K M
AU  - Reed KM
FAU - Rabova, M
AU  - Rabova M
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PL  - Switzerland
TA  - Cytogenet Genome Res
JT  - Cytogenetic and genome research
JID - 101142708
RN  - 0 (DNA, Ribosomal)
SB  - IM
MH  - Animals
MH  - Chromosome Banding
MH  - Chromosome Mapping
MH  - *Chromosomes/ultrastructure
MH  - DNA, Ribosomal/*genetics
MH  - In Situ Hybridization, Fluorescence
MH  - Karyotyping
MH  - North America
MH  - Nucleolus Organizer Region
MH  - Silver Staining
MH  - Umbridae/classification/*genetics
EDAT- 2003/04/17 05:00
MHDA- 2003/05/14 05:00
CRDT- 2003/04/17 05:00
PHST- 2003/01/04 00:00 [received]
PHST- 2003/01/07 00:00 [accepted]
PHST- 2003/04/17 05:00 [pubmed]
PHST- 2003/05/14 05:00 [medline]
PHST- 2003/04/17 05:00 [entrez]
AID - 69800 [pii]
AID - 10.1159/000069800 [doi]
PST - ppublish
SO  - Cytogenet Genome Res. 2002;98(2-3):194-8. doi: 10.1159/000069800.