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14:28
Peptide-based Identification of Functional Motifs and their Binding Partners
Published on: June 30, 2013
A proapoptotic peptide derived from reovirus outer capsid protein {micro}1 has membrane-destabilizing activity
Jae-Won Kim1, Sangbom M Lyi, Colin R Parrish
1Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Hungerford Hill Road, Ithaca, New York 14853, USA.
Journal of Virology
|November 26, 2010
Summary
The reovirus outer capsid protein mu1
Area of Science:
- Virology
- Cell Biology
- Biochemistry
Background:
- Reovirus outer capsid protein mu1 mediates cell entry and apoptosis.
- Specific regions of mu1, particularly residues 582-611 (helix 1), are critical for apoptosis.
- Residues 594 and 595 within helix 1 modulate viral entry and apoptosis efficiency.
Purpose of the Study:
- To investigate the biological properties of synthesized peptides representing helix 1 (H1) and helix 3 (H3) of reovirus mu1.
- To determine the role of H1 and H3 peptides in membrane destabilization, cytotoxicity, and bactericidal activity.
Main Methods:
- Chemical synthesis of peptides representing helix 1 (H1) and helix 3 (H3) of reovirus mu1.
- Liposome leakage assays to assess membrane destabilization.
- Cytotoxicity assays on eukaryotic cells (L929) and bacterial cells.
Main Results:
- H1 peptide induced concentration- and size-dependent liposome leakage, indicating membrane destabilization.
- H1 peptide, but not H3 or modified H1 peptides, exhibited cytotoxicity in eukaryotic cells.
- H1 peptide application led to rapid intracellular calcium elevation in L929 cells.
- H1 peptide demonstrated bactericidal activity against bacteria.
Conclusions:
- The H1 region of reovirus mu1 destabilizes cellular membranes, leading to organelle molecule release.
- This membrane destabilization mechanism contributes to the proapoptotic and necrotic functions of reovirus.
- H1 peptide's activity extends to bactericidal effects, suggesting broader membrane-disrupting capabilities.
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