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Updated: Jun 21, 2026
09:29
A Complete Pipeline for Isolating and Sequencing MicroRNAs, and Analyzing Them Using Open Source Tools
Published on: August 21, 2019
Evidence for human microRNA-offset RNAs in small RNA sequencing data
David Langenberger1, Clara Bermudez-Santana, Jana Hertel
1Department of Computer Science, University of Leipzig, Leipzig, Germany.
Bioinformatics (Oxford, England)
|July 9, 2009
Summary
MicroRNA-offset-RNAs (moRNAs) are found in human microRNA precursors, though at low levels. These moRNAs originate from evolutionarily ancient microRNA families, suggesting an old biological role.
Area of Science:
- Molecular Biology
- Genomics
- Evolutionary Biology
Background:
- MicroRNA-offset-RNAs (moRNAs) are a recently identified class of small RNAs.
- These abundant small RNAs were initially detected in a basal chordate species.
Purpose of the Study:
- To investigate the presence and characteristics of moRNAs in human microRNA precursors.
- To explore the evolutionary origins and expression patterns of moRNAs in humans.
Main Methods:
- Analysis of short read sequencing data from human samples.
- Comparative analysis of microRNA precursor sequences and their evolutionary age.
Main Results:
- moRNAs are produced from human microRNA precursors, but at low expression levels.
- The expression of moRNAs is independent of the expression of their associated microRNAs.
- moRNA-producing microRNA precursors are predominantly evolutionarily ancient, predating many recent microRNA families.
Conclusions:
- moRNAs are conserved across species, extending from basal chordates to humans.
- The prevalence of moRNAs in ancient microRNA families suggests a long-standing biological function.
- Further research is needed to elucidate the functional significance of moRNAs in human biology.
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