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Updated: Jan 24, 2026
Multi-Faceted Mass Spectrometric Investigation of Neuropeptides in Callinectes sapidus
Published on: May 31, 2022
CPD-1 can compensate for EGL-21 to process neuropeptides
David C Khawand1, Amy K Clippinger1, Michael Ailion1
1Department of Biochemistry, University of Washington, Seattle, WA USA.
None:
Carboxypeptidase D has been thought to process neuropeptides, though its role has not been fully characterized. Since specific neuropeptides regulate the defecation motor program of C. elegans , we used genetic analysis to determine how loss of the worm carboxypeptidase D ortholog CPD-1 affects defecation. We found that cpd-1 mutants do not have defecation defects but enhance the defecation defects of egl-21 mutants lacking carboxypeptidase E, a major neuropeptide processing enzyme. We also found that CPD-1 acts in intestinal cells and possibly GABAergic neurons to promote defecation. These results suggest that CPD-1 can process neuropeptides, specifically in the absence of EGL-21 .
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