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Updated: Jul 6, 2026
04:59
Single Nucleotide Polymorphism-sensitive FISH Detection of Locus-specific Ribosomal RNA Transcription in Drosophila melanogaster
Published on: March 28, 2025
Mouse ribosomal RNA genes contain multiple differentially regulated variants.
Hung Tseng1, Weichin Chou, Junwen Wang
1Department of Dermatology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America. htsengpe@mail.med.upenn.edu
Plos One
|March 28, 2008
Summary
Researchers identified seven mouse ribosomal DNA (rDNA) variants (v-rDNA) with distinct expression patterns. This provides the first molecular evidence for tissue-specific regulation of a subset of rDNA.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- Cytogenetic studies indicate variable ribosomal DNA (rDNA) chromosomal locus activity across cell types.
- Ribosomal DNA (rDNA) polymorphism is established in humans and mice, but molecular identification of individually regulated, tissue-specific variants has been elusive.
Purpose of the Study:
- To molecularly clone and characterize distinct mouse ribosomal DNA (rDNA) variants.
- To investigate the tissue-specific expression profiles of these identified rDNA variants.
Main Methods:
- Molecular cloning of seven mouse rDNA variants (v-rDNA) based on conserved restriction fragment length polymorphisms (RFLPs).
- Sequence analysis to identify variant-specific single nucleotide polymorphisms (SNPs) in the transcribed region.
- Development of variant-specific PCR assays to analyze v-rDNA expression in various tissues.
Main Results:
- Identified seven mouse rDNA variants (v-rDNA) with copy numbers ranging from 4 to 15 per variant.
- Discovered variant-specific single nucleotide polymorphisms (SNPs) enabling the development of specific PCR assays.
- Observed distinct expression profiles: three v-rDNAs constitutively active, two selectively active, and two silent across different tissues and mouse strains.
Conclusions:
- The mouse rDNA array comprises genetically distinct variants.
- A subset of these rDNA variants is regulated in a tissue-specific manner.
- Provides the first molecular evidence for cell-type-specific regulation of a subset of rDNA.
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