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Rubiscolin, a delta selective opioid peptide derived from plant Rubisco
1Division of Food Bioscience and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan.
FEBS Letters
|December 14, 2001
Summary
Researchers discovered opioid peptides, rubiscolin-5 and rubiscolin-6, within spinach D-ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). These plant-derived peptides exhibit delta receptor selectivity and antinociceptive effects in mice.
Area of Science:
- Biochemistry
- Pharmacology
- Plant Science
Background:
- D-ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is a crucial enzyme in plant photosynthesis.
- Specific amino acid sequences within proteins can possess biological activity.
- Opioid peptides are known for their roles in pain modulation.
Purpose of the Study:
- To investigate potential opioid activity within the spinach Rubisco large subunit.
- To synthesize and characterize novel bioactive peptides derived from plant Rubisco.
- To evaluate the antinociceptive properties of these plant-derived peptides.
Main Methods:
- Sequence analysis of spinach Rubisco to identify potential opioid motifs.
- Chemical synthesis of identified peptide sequences (YPLDL and YPLDLF).
- In vitro opioid receptor binding assays (delta receptor) and mouse vas deferens assays.
- In vivo antinociceptive activity assessment in mice via intracerebroventricular and oral administration.
Main Results:
- Two peptides, named rubiscolin-5 (YPLDL) and rubiscolin-6 (YPLDLF), were synthesized from spinach Rubisco.
- Both rubiscolin-5 and rubiscolin-6 demonstrated selective binding to the delta opioid receptor.
- Rubiscolin-5 and -6 exhibited significant antinociceptive effects in mice following various administration routes.
Conclusions:
- This study presents the first instance of bioactive opioid peptides isolated from plant Rubisco.
- Rubiscolin-5 and -6 represent novel endogenous ligands for the delta opioid receptor with therapeutic potential.
- Plant-derived peptides offer a new avenue for exploring pain management strategies.
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