Preliminary karyotype and chromosomal localization of ribosomal DNA sites in white spruce using fluorescence in situ hybridization
1993
Brown, G.R. | Amarasinghe, V. | Kiss, G. | Carlson, J.E.
We have localized the major ribosomal DNA (rDNA) loci on metaphase chromosomes and in interphase nuclei of white spruce 2n = 24) by fluorescence in situ hybridization. Hybridization sites of the biotin-labelled rDNA probe were detected using antibody-fluorochrome conjugates and a confocal laser scanning microscope. White spruce has at least 12, and possibly as many as 14, rDNA sites, 1 site present on each of seven separate chromosome pairs. This is one of the highest numbers of rDNA loci yet reported among plant species. The position of the rDNA loci together with secondary constriction patterns permit, for the first time, all homologous pairs of white spruce chromosomes to be distinguished. We discuss the application of molecular cytogenetics in studies relating to the organization and evolution of DNA sequences within conifer genomes.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library