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Updated: Jan 13, 2026
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Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells
Published on: June 15, 2013
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Structural Communication Between C-Peptide and Insulin Within the Proinsulin Molecule
Rubing Shao1,2, Maroof Alam1, Leena Haataja1
1Division of Metabolism, Endocrinology & Diabetes, University of Michigan, Brehm Tower rm 5112, 1000 Wall Street, Ann Arbor, MI 48105, USA.
International Journal of Molecular Sciences
|January 10, 2026
Summary
The human C-peptide
Area of Science:
- Molecular Biology
- Endocrinology
- Genetics
Background:
- The biological role of human C-peptide, a component of proinsulin, is not fully understood.
- C-peptide has conserved residues suggesting co-evolution with insulin.
- Genetic studies link C-peptide variants to glycemic control alterations.
Purpose of the Study:
- To investigate the role of the amino-terminal portion of C-peptide in proinsulin folding, trafficking, and insulin biogenesis.
- To explore how C-peptide missense mutations affect proinsulin processing and secretion.
- To examine the interaction between variant and wildtype proinsulin.
Main Methods:
- Bioengineering missense mutations in the amino-terminal C-peptide region.
- Assessing proinsulin folding and trafficking efficiency.
- Analyzing the physical interaction between mutant and wildtype proinsulin.
- Evaluating the impact on insulin biogenesis.
Main Results:
- Engineered C-peptide mutations impair proinsulin folding and trafficking.
- These mutations reduce overall insulin biogenesis.
- Variant proinsulin interacts with wildtype proinsulin, altering trafficking based on expression ratios.
Conclusions:
- The amino-terminal C-peptide influences proinsulin folding and trafficking.
- C-peptide mutations can negatively impact human insulin production.
- C-peptide plays a crucial role in regulating insulin biosynthesis and secretion.
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