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Peptideins: Navigating the gray zone of the proteome
Giulia Pesce1, Salvador Ventura1
1Institut de Biotecnologia I de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Spain; Departament de Bioquímica I Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Trends in Biochemical Sciences
|July 2, 2026
Summary
Researchers introduce peptideins, endogenous proteins with evidence of synthesis but unknown function. This concept cautiously expands the human proteome, distinguishing translation from molecular detection and function.
Area of Science:
- Proteomics
- Molecular Biology
- Genomics
Background:
- Translated sequences are typically classified as either genes or noise.
- The biological status of some synthesized endogenous proteins remains unresolved.
- The TransCODE Consortium has investigated novel protein entities.
Purpose of the Study:
- To introduce and define the concept of "peptideins".
- To propose a framework for classifying endogenous proteins with evidence of synthesis but unresolved biological status.
- To expand the understanding of the human proteome.
Main Methods:
- Analysis of translated sequences from the TransCODE Consortium study.
- Identification of endogenous proteins with evidence of synthesis.
- Evaluation of biological status and functional evidence.
Main Results:
- Introduction of the term "peptideins" for specific endogenous proteins.
- Demonstration of evidence for synthesis of these peptideins.
- Highlighting the unresolved biological and functional status of peptideins.
Conclusions:
- Peptideins represent a distinct category of endogenous proteins.
- The concept of peptideins allows for cautious expansion of the human proteome.
- Distinguishing between translation, molecular detection, and biological function is crucial for understanding peptideins.
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