
Faculty Research 1990 - 1999
High resolution mapping of Xenopus laevis 5S and ribosomal RNA genes by EM in situ hybridization.
Document Type
Article
Publication Date
1990
Keywords
Cells-Cultured, Chromosome-Mapping, DNA-Probes, Immunohistochemistry, Interphase, Microscopy-Electron, Mitosis, Nucleic-Acid-Hybridization, Oocytes: an, RNA-Probes, RNA-Ribosomal: ge, RNA-Ribosomal-5S: ge, SUPPORT-U-S-GOVT-P-H-S, Translocation-(Genetics), Xenopus-laevis: ge
First Page
144
Last Page
152
JAX Source
Cytometry 1990;11(1):144-52
Grant
GM23241
Abstract
We have developed a modification of in situ hybridization at the electron microscope level that permits simultaneous detection of at least two sequences. Probes are labelled with either biotin or AAF and detected with two distinct sizes of colloidal gold. This protocol has been applied to map the positions of Xenopus laevis oocyte-type 5S genes relative to ribosomal precursor genes in several independently derived cell lines. The results for the line TRXO, which expresses some oocyte 5S RNA, indicate that this inappropriate expression is not due to translocation from telomeric sites into the nucleolus organizer, as previously hypothesized. In addition we found that four other Xenopus cell lines, none of which express these genes, also contain distinct 5S oocyte translocations. These results suggest that an alteration in chromosome position is insufficient to result in gene activation and that sequences which are telomeric-proximal are exceptionally prone to translocation.
Recommended Citation
Narayanswami S,
Hamkalo BA.
High resolution mapping of Xenopus laevis 5S and ribosomal RNA genes by EM in situ hybridization. Cytometry 1990;11(1):144-52