Karyotype differentiation of four Cestrum species ( Solanaceae ) based on the physical mapping of repetitive DNA
Genet. mol. biol
; 29(1): 97-104, 2006. ilus, tab
Article
in English
| LILACS
| ID: lil-424743
Responsible library:
BR26.1
RESUMO
We studied the karyotypes of four Brazilian Cestrum species (C. amictum, C. intermedium, C. sendtnerianum and C. strigilatum) using conventional Feulgen staining, C-Giemsa and C-CMA3/DAPI banding, induction of cold-sensitive regions (CSRs) and fluorescent in situ hybridization (FISH) with rDNA probes. We found that the karyotypes of all four species was 2n = 2x = 16, with, except for the eighth acrocentric pair, a predominance of meta- and submetacentric chromosomes and various heterochromatin classes. Heterochromatic types previously unreported in Cestrum as neutral C-CMA3(0)/DAPI0 bands, CMA3+ bands not associated with NORs, and C-Giemsa/CSR/DAPI- bands were found. The heterochromatic blocks varied in size, number, position and composition. The 45S rDNA probe preferentially located in the terminal and subterminal regions of some chromosomes, while 5S rDNA appeared close to the centromere of the long arm of pair 8. These results suggest that karyotype differentiation can occur mainly due to changes in repetitive DNA, with little modification in the general composition of the conventionally stained karyotype.
Full text:
Available
Collection:
International databases
Database:
LILACS
Main subject:
Microsatellite Repeats
/
Solanaceae
Language:
English
Journal:
Genet. mol. biol
Journal subject:
Genetics
Year:
2006
Document type:
Article
Affiliation country:
Brazil
Institution/Affiliation country:
Universidade Estadual de Londrina/BR