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Updated: Aug 7, 2026
08:23
De novo Identification of Actively Translated Open Reading Frames with Ribosome Profiling Data
Published on: February 18, 2022
A novel recently evolved gene C19orf24 encodes a non-classical secreted protein
Xin-Rong Wang1, Yu-Bo Zhou, Feng Liu
1School of Life Science and Technology, Shanghai Jiao Tong University, Shanghai, China.
Cellular & Molecular Biology Letters
|July 19, 2006
Summary
Researchers identified a novel human protein, C19orf24, that is secreted extracellularly through a unique pathway. This recently evolved gene, found only in humans and chimpanzees, shows purifying selection, suggesting a vital biological role.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- Secreted proteins are crucial for biological processes and drug development.
- The mechanisms of non-classical protein secretion are not fully understood.
Purpose of the Study:
- To isolate and characterize a novel human non-classical secreted protein encoded by C19orf24.
- To elucidate the secretion pathway and biological significance of C19orf24.
Main Methods:
- Subcellular localization studies in HeLa cells.
- Deglycosylation analysis using PNGase F.
- Reverse transcription-PCR (RT-PCR) for gene expression analysis.
- Evolutionary analysis of synonymous and non-synonymous substitution rates (dN/dS).
Main Results:
- C19orf24 is a novel human non-classical secreted protein, lacking a signal peptide and independent of brefeldin A (BFA) inhibition.
- It does not co-localize with the Golgi apparatus, indicating a novel secretion pathway.
- C19orf24 lacks N-glycosylation sites and is exclusively expressed in the human liver, particularly in normal tissue.
- This gene is recently evolved, found only in Homo sapiens and Pan troglodytes, and has undergone purifying selection.
Conclusions:
- C19orf24 utilizes a previously unknown non-classical secretion pathway.
- Its tissue-specific expression and evolutionary conservation suggest a critical, potentially irreplaceable function in humans.
- C19orf24 represents a potential target for future research in liver biology and therapeutics.
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