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Updated: Sep 4, 2025
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A Rapid High-throughput Method for Mapping Ribonucleoproteins RNPs on Human pre-mRNA
Published on: December 2, 2009
11.8K
A high-resolution map of human RNA translation
Sonia P Chothani1, Eleonora Adami2, Anissa A Widjaja1
1Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore, Singapore 169857, Singapore.
Molecular Cell
|July 16, 2022
Summary
Researchers identified 7,767 translated small open reading frames (smORFs) in human cells and tissues, revealing novel microproteins and conserved sequences. This atlas enhances our understanding of the translated human genome.
Area of Science:
- Genomics
- Proteomics
- Molecular Biology
Background:
- Translated small open reading frames (smORFs) encode microproteins with regulatory functions.
- Genome-wide identification of smORFs has been challenging.
- Understanding the full scope of the translated human genome is incomplete.
Purpose of the Study:
- To identify and characterize translated smORFs across diverse human cell types and tissues.
- To provide a comprehensive atlas of high-confidence translated smORFs.
- To investigate the conservation and regulation of smORFs.
Main Methods:
- Ribosome profiling across six human cell types and five tissues.
- Bioinformatic analysis to identify smORFs with protein-like translational profiles.
- Integration with mass spectrometry datasets to confirm protein-level evidence.
Main Results:
- Identified 7,767 translated smORFs with protein-like translational signatures.
- Discovered cell-type and tissue-specific smORFs, alongside conserved sequences.
- Confirmed 603 small peptides at the protein level using mass spectrometry.
- Observed coordinated changes in translational efficiency for upstream and main ORFs.
Conclusions:
- The human genome encodes a substantial number of translated smORFs with diverse characteristics.
- This study provides a valuable resource for understanding microprotein function and regulation.
- The findings contribute to a more complete map of the translated human proteome.
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