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Methods for the Discovery of Novel Compounds Modulating a Gamma-Aminobutyric Acid Receptor Type A Neurotransmission
Published on: August 16, 2018
The first gamma-carboxyglutamate-containing neuropeptide
Jennifer A Jakubowski1, Nathan G Hatcher, Fang Xie
1Department of Chemistry and the Beckman Institute, University of Illinois, Urbana, 61801, USA.
Neurochemistry International
|March 9, 2006
Summary
Scientists discovered a rare carboxylation modification on a D-peptide in the sea slug Aplysia californica. This carboxylated neuropeptide, found in insulin-producing neurons, suggests a novel signaling role in the nervous system.
Area of Science:
- Neuroscience
- Biochemistry
- Marine Biology
Background:
- Post-translational modifications are crucial for peptide transmitter activity in neuronal signaling.
- The sea slug Aplysia californica serves as a model organism for studying neurobiology.
Purpose of the Study:
- To identify and characterize post-translational modifications on peptides involved in Aplysia nervous system signaling.
- To investigate the presence and nature of a rare carboxylation modification on an insulin prohormone D-peptide.
Main Methods:
- Liquid chromatography purification.
- Electrospray ionization and nanoelectrospray ionization-ion trap-mass spectrometry (ESI- and nanoESI-MS) for peptide identification and characterization.
- Analysis of peptide secretion from the central nervous system.
Main Results:
- Confirmed the presence of the Aplysia insulin D-peptide in AI-producing neurons.
- Demonstrated gamma-carboxylation on the single glutamate residue of the Aplysia insulin D-peptide.
- Observed secretion of the carboxylated D-peptide and other AI-related peptides from the central nervous system upon stimulation.
Conclusions:
- The Aplysia gamma-carboxy D-peptide is the first reported carboxylated neuropeptide.
- The secreted carboxylated D-peptide suggests a potential signaling role within the Aplysia nervous system.
- This finding expands the known repertoire of neuropeptide modifications and functions.
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