Linked Life Data

8919917

Source:http://linkedlifedata.com/resource/pubmed/id/8919917

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-1-2
pubmed:abstractText
A technique to detect DNA sequences on extended DNA fibres (EDF) prepared from interphase nuclei from tomato (Lycopersicon esculentum) and Arabidopsis thaliana leaves by fluorescence in situ hybridization (FISH) is described. Three nuclear lysis procedures have been tested for their ability to decondense chromatin and to generate highly extended intact DNA fibres on microscopic slides. DNA probes of various sizes have been used in FISH experiments to EDFs to establish the resolution and sensitivity of the technique. The fluorescent signals of a 5S rDNA probe hybridized to tomato EDFs revealed continuous strings of about 200 microns, that corresponded to a molecular size of about 660 kb. In A. thaliana, a contig of three cosmids spanning a genomic region with a total length of about 89 kb was analysed. By means of multicolour hybridization the physical positions of the cosmids were visualized as red and green fluorescence strings with overlapping regions in yellow. Comparison of the length of the fluorescent signals with the molecular data revealed a stretching degree of the DNA fibres at 3.27 kb microns-1, which is close to the Watson-Crick DNA length estimate of 2.9 kb microns-1. Other experiments on small size molecular probes with both lambda clones (13.5-17 kb insert sizes) and plasmids (4.2 and 5 kb) in a contig of A. thaliana, and the 5S rDNA region in tomato showed close agreement with molecular data. The lower limit of the detection, which was established in a hybridization experiment with two DNA probes from the 45S ribosomal gene on extended fibres of tomato, was about 0.7 kb. Consistent patterns of alternating fluorescent red and green spots were obtained reflecting the tandemly repeated arrangement of the 18S and 25S ribosomal sequences. On the basis of the microscopic distance between these hybridization spots the size of the ribosomal unit was estimated at 8.2 kb. This implies a drastic improvement of high-resolution physical mapping of DNA sequences by FISH on plant DNA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0960-7412
pubmed:author
pubmed:issnType
Print
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
421-30
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
High-resolution physical mapping in Arabidopsis thaliana and tomato by fluorescence in situ hybridization to extended DNA fibres.
pubmed:affiliation
Department of Genetics, Wageningen Agricultural University, Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't