| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Dept. of Neuroscience, Univ. of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States
2 Dept. of Chemistry and School of Pharmacy, Univ. of Wisconsin-Madison, Madison, Wisconsin, United States
3 Laoboratory of Developmental Physiology, Genomics and Proteomics, Katholieke Universiteit Leuven, Leuven, Belgium
4 University of Pennsylvania School of Medicine, United States; Dept. of Neuroscience, Univ. of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States; University of Pennsylvania School of Medicine
* To whom correspondence should be addressed. E-mail: nusbaum{at}mail.med.upenn.edu.
Pyrokinin (PK) peptides localize to the central and peripheral nervous systems of arthropods, but their actions in the CNS have yet to be studied in any species. Here, we identify PK peptide family members in the crab Cancer borealis and characterize their actions on the gastric mill (chewing) and pyloric (filtering) motor circuits in the stomatogastric ganglion (STG). We identified PK-like immunolabeling in the STG neuropil, in projection neuron inputs to this ganglion, and in the neuroendocrine pericardial organs. By combining MALDI mass spectrometry (MS) and ESI tandem MS techniques, we identified the amino acid sequences of two C. borealis pyrokinins (CabPK-I, CabPK-II). Both CabPKs contain the PK family-specific carboxy-terminal amino acid sequence (FXPRLamide). PK superfusion to the isolated STG had little influence on the pyloric rhythm but excited many gastric mill neurons and consistently activated the gastric mill rhythm. Both CabPKs had comparable actions in the STG, and these actions were equivalent to those of Pevpyrokinin (shrimp) and Leucopyrokinin (cockroach). The PK-elicited gastric mill rhythm usually occurred without activation of the projection neuron MCN1. MCN1, which does not contain CabPKs, effectively drives the gastric mill rhythm and at such times is also a gastric mill central pattern generator (CPG) neuron. Because the PK-elicited gastric mill rhythm is independent of MCN1, the underlying core CPG of this rhythm is different from the one responsible for the MCN1-elicited rhythm. Thus neuromodulation, which commonly alters motor circuit output without changing the core CPG, can also change the composition of this core circuit.
This article has been cited by other articles:
|
|
 |
|
  N. Spitzer, G. Cymbalyuk, H. Zhang, D. H. Edwards, and D. J. Baro Serotonin Transduction Cascades Mediate Variable Changes in Pyloric Network Cycle Frequency in Response to the Same Modulatory Challenge J Neurophysiol, June 1, 2008; 99(6): 2844 - 2863. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. M. Blitz, R. S. White, S. R. Saideman, A. Cook, A. E. Christie, F. Nadim, and M. P. Nusbaum A newly identified extrinsic input triggers a distinct gastric mill rhythm via activation of modulatory projection neurons J. Exp. Biol., March 15, 2008; 211(6): 1000 - 1011. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. P. Beenhakker, M. S. Kirby, and M. P. Nusbaum Mechanosensory Gating of Proprioceptor Input to Modulatory Projection Neurons J. Neurosci., December 26, 2007; 27(52): 14308 - 14316. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. R. Smarandache and W. Stein Sensory-induced modification of two motor patterns in the crab, Cancer pagurus J. Exp. Biol., August 15, 2007; 210(16): 2912 - 2922. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. R. Saideman, D. M. Blitz, and M. P. Nusbaum Convergent Motor Patterns from Divergent Circuits J. Neurosci., June 20, 2007; 27(25): 6664 - 6674. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
