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Updated: Jun 27, 2026
09:37
An Integrated Approach for Microprotein Identification and Sequence Analysis
Published on: July 12, 2022
Identification and characterization of new long conserved noncoding sequences in vertebrates
Yoshiyuki Sakuraba1, Toru Kimura, Hiroshi Masuya
1RIKEN Genomic Sciences Center, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan. yoshiyuki.sakuraba@stjude.org
Summary
Researchers identified 611 long conserved noncoding sequences (LCNS) between humans and mice. These sequences are not mutational cold spots, indicating natural selection eliminates mutations during evolution.
Area of Science:
- Genomics
- Comparative genomics
- Evolutionary biology
Background:
- Comparative sequence analyses reveal conserved genomic DNA, including noncoding sequences, across species.
- Ultraconserved elements (UCEs) are defined as aligned sequences >200 bp with 100% identity in human, mouse, and rat.
Purpose of the Study:
- To identify and characterize long conserved noncoding sequences (LCNS) between humans and mice.
- To investigate whether LCNS are functionally important or mutational cold spots by measuring mutation frequencies.
Main Methods:
- Whole-genome comparisons between human and mouse to identify conserved noncoding sequences >500 bp with >95% identity.
- Direct measurement of ENU-induced germline mutation frequencies within LCNS in mice.
- Screening of approximately 40.7 Mb of mouse genome for mutations.
Main Results:
- Identified 611 LCNS, including 473 novel sequences not overlapping with UCEs.
- LCNS are distributed genome-wide, often clustered in gene-poor regions, and conserved across vertebrates but not invertebrates.
- Mutation frequencies in LCNS were equivalent to other genomic regions, including coding sequences and introns.
Conclusions:
- LCNS are not mutational cold spots; mutations occur at similar frequencies as in other genomic regions.
- The high conservation of LCNS suggests they are functionally important and subject to strong purifying selection.
- Mutations in LCNS are likely eliminated by natural selection, contributing to their evolutionary conservation.
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