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Title: Mapping of neuropeptide Y expression in Octopus brains
Abstract

Neuropeptide Y (NPY) is an evolutionarily conserved neurosecretory molecule implicated in a diverse complement of functions across taxa and in regulating feeding behavior and reproductive maturation inOctopus. However, little is known about the precise molecular circuitry of NPY‐mediated behaviors and physiological processes, which likely involve a complex interaction of multiple signal molecules in specific brain regions. Here, we examined the expression of NPY throughout theOctopuscentral nervous system. The sequence analysis ofOctopusNPY precursor confirmed the presence of both, signal peptide and putative active peptides, which are highly conserved across bilaterians.In situhybridization revealed distinct expression of NPY in specialized compartments, including potential “integration centers,” where visual, tactile, and other behavioral circuitries converge. These centers integrating separate circuits may maintain and modulate learning and memory or other behaviors not yet attributed to NPY‐dependent modulation inOctopus. Extrasomatic localization of NPY mRNA in the neurites of specific neuron populations in the brain suggests a potential demand for immediate translation at synapses and a crucial temporal role for NPY in these cell populations. We also documented the presence of NPY mRNA in a small cell population in the olfactory lobe, which is a component of theOctopusfeeding and reproductive control centers. However, the molecular mapping of NPY expression only partially overlapped with that produced by immunohistochemistry in previous studies. Our study provides a precise molecular map of NPY mRNA expression that can be used to design and test future hypotheses about molecular signaling in variousOctopusbehaviors.

 
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Award ID(s):
1645219
NSF-PAR ID:
10458062
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Morphology
Volume:
281
Issue:
7
ISSN:
0362-2525
Page Range / eLocation ID:
p. 790-801
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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