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Quantitative Comparison of cis-Regulatory Element (CRE) Activities in Transgenic Drosophila melanogaster
Published on: December 19, 2011
Genomic regulatory blocks underlie extensive microsynteny conservation in insects
Pär G Engström1, Shannan J Ho Sui, Oyvind Drivenes
1Computational Biology Unit, Bergen Center for Computational Science, University of Bergen, Bergen 5008, Norway.
Genome Research
|November 9, 2007
Summary
Genomic regulatory blocks (GRBs) in insects retain gene order to preserve noncoding elements crucial for development. These conserved regions highlight ancient genome organization across metazoans.
Area of Science:
- Genomics
- Developmental Biology
- Evolutionary Biology
Background:
- Insect genomes exhibit larger blocks of conserved gene order (microsynteny) than random models predict.
- Highly conserved noncoding elements (HCNEs) are retained in arrays within these microsyntenic blocks.
Purpose of the Study:
- To investigate the role of microsynteny in maintaining HCNE arrays in insect genomes.
- To compare insect genomic regulatory blocks (GRBs) with those previously described in vertebrates.
- To explore the evolutionary conservation and regulatory function of GRBs in insects.
Main Methods:
- Comparative analysis of five Drosophila genomes.
- Identification and mapping of HCNEs and synteny blocks.
- Analysis of core promoter differences between target and unrelated genes.
- Cross-species comparison of noncoding element conservation between Drosophila, Anopheles gambiae, and Aedes aegypti.
Main Results:
- HCNE density peaks centrally in large synteny blocks containing developmental regulatory genes.
- HCNE arrays span both target developmental genes and unrelated neighboring genes.
- Differences in core promoters explain varied enhancer responsiveness.
- GRB boundaries correlate with synteny blocks, HCNE arrays, and Polycomb binding regions.
- Insect GRBs show structural and functional equivalence to vertebrate GRBs, with conserved noncoding elements in mosquito orthologs.
Conclusions:
- Microsynteny in insects is retained to maintain HCNE arrays, forming genomic regulatory blocks (GRBs).
- GRBs are ancient features of metazoan genomes, conserved across insects and vertebrates.
- These findings provide insights into genome evolution and gene regulation.
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