A global analysis of Caenorhabditis elegans operons
Thomas Blumenthal1, Donald Evans, Christopher D Link
1Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Box B121, 4200 E. 9th Avenue, Denver, Colorado 80262, USA. tom.blumenthal@uchsc.edu
Nature
|June 21, 2002
Summary
The nematode Caenorhabditis elegans has at least 1,000 operons, which are gene clusters transcribed together. This discovery reveals novel functional relationships and expands our understanding of gene regulation in this model organism.
Area of Science:
- Genomics
- Molecular Biology
- Developmental Biology
Background:
- Operons are rare in animals, with Caenorhabditis elegans being a notable exception.
- Operons involve polycistronic transcription followed by processing into monocistronic mRNAs via trans-splicing.
- Previous identification of operons in C. elegans was limited, hindering a full understanding of their prevalence and function.
Purpose of the Study:
- To systematically identify and quantify operons in the Caenorhabditis elegans genome.
- To determine the extent of SL2 trans-splicing in downstream operon genes.
- To explore potential functional relationships among co-transcribed genes.
Main Methods:
- Genome-wide microarray analysis to detect SL2-containing mRNAs.
- Bioinformatic analysis of gene clusters and genomic arrangements.
- Comparison with existing complementary DNA sequence data.
Main Results:
- Identification of approximately 1,200 genes enriched for SL2 trans-splicing.
- Genomic analysis confirmed >90% of these as downstream operon genes, organized into 790 distinct operons.
- Estimated at least 1,000 operons in the C. elegans genome, comprising ~15% of all genes.
Conclusions:
- The C. elegans genome harbors a significantly larger number of operons than previously known.
- Co-transcription of functionally related genes within operons is common, suggesting coordinated gene regulation.
- The identified operons provide a resource for discovering new functional gene relationships.
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