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Xenin: the oldest after insulin?
Alexander T Maryanovich1, Dmitry Yu Kormilets2, Andrey D Polyanovsky3
1Mechinkov Northwestern State Medical University, St. Petersburg, Russia. atm52@mail.ru.
Molecular Biology Reports
|January 18, 2018
Summary
Xenin, a human gastric peptide, shows significant evolutionary presence. This regulatory peptide
Area of Science:
- Biochemistry
- Evolutionary Biology
- Molecular Biology
Background:
- Xenin is a regulatory peptide initially identified in human gastric mucosa.
- Its evolutionary history and broad significance are not fully understood.
Purpose of the Study:
- To investigate the evolutionary presence and conservation of xenin motifs across diverse species.
- To determine the ancient origins and potential significance of xenin.
Main Methods:
- Utilized the MEDLINE protein database (33 million molecules, 11 billion amino acid residues).
- Employed a custom computer program to search for xenin motifs in protein primary structures.
- Analyzed protein sequences across a wide taxonomic range.
Main Results:
- Xenin motifs with 40% homology to human xenin were found in prokaryotes.
- Homology increased to 84-96% in single-cell algae and plants.
- Complete homology was observed starting from bony fishes.
Conclusions:
- The regulatory peptide xenin is present much earlier in evolutionary history than previously assumed.
- Xenin appears to be a highly conserved and ancient regulatory peptide.
- Its ancient origins suggest a fundamental biological role across diverse life forms.
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