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An Integrated Approach for Microprotein Identification and Sequence Analysis
Published on: July 12, 2022
Genome-Level Analysis of Selective Constraint without Apparent Sequence Conservation.
Olga A Vakhrusheva1, Georgii A Bazykin, Alexey S Kondrashov
1Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia.
Genome Biology and Evolution
|February 19, 2013
Summary
Functional conservation of DNA segments can persist despite sequence divergence. Homologous introns in insects and vertebrates retain regulatory function even when sequences are unalignable, indicating strong selective pressure.
Area of Science:
- Genomics
- Evolutionary Biology
- Molecular Biology
Background:
- Homologous DNA sequences often exhibit conserved function.
- Noncoding DNA, such as introns, can maintain ancestral functions even after significant sequence divergence.
- Investigating functional conservation without sequence similarity is crucial for understanding genome evolution.
Purpose of the Study:
- To investigate the genomic-scale phenomenon of functional conservation in homologous noncoding DNA segments.
- To determine if conserved function persists in introns even when sequence similarity is undetectable.
- To explore the evolutionary dynamics of introns across different species pairs.
Main Methods:
- Comparative genomics analysis of homologous introns in two quartets of insect and vertebrate species.
- Examination of sequence similarity and conservation patterns in introns between moderately distant genome pairs.
- Analysis of intron length and presence/absence to infer selective pressures.
Main Results:
- Introns with regulatory or conserved segments in one genome pair retained conserved segments in the other pair, despite lacking sequence similarity.
- Preserved introns between genome pairs were generally longer and contained conserved segments within their own pair compared to lost introns.
- Selective constraint on homologous DNA segments can persist even when sequences become unalignable.
Conclusions:
- Functional conservation of noncoding DNA can be maintained independently of sequence similarity.
- Selective pressure, likely due to conserved ancestral function, plays a significant role in preserving noncoding DNA elements.
- This study highlights the importance of considering functional conservation beyond sequence alignment in evolutionary genomics.
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