Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 7-Day Trial for You or Your Team.

Learn More →

Circadian regulation of the lark RNA‐binding protein within identifiable neurosecretory cells

Circadian regulation of the lark RNA‐binding protein within identifiable neurosecretory cells Molecular genetic analysis indicates that rhythmic changes in the abundance of the Drosophila lark RNA‐binding protein are important for circadian regulation of adult eclosion (the emergence or ecdysis of the adult from the pupal case). To define the tissues and cell types that might be important for lark function, we have characterized the spatial and developmental patterns of lark protein expression. Using immunocytochemical or protein blotting methods, lark can be detected in late embryos and throughout postembryonic development, from the third instar larval stage to adulthood. At the late pupal (pharate adult) stage, lark protein has a broad pattern of tissue expression, which includes two groups of crustacean cardioactive peptide (CCAP)‐containing neurons within the ventral nervous system. In other insects, the homologous neurons have been implicated in the physiological regulation of ecdysis. Whereas lark has a nuclear distribution in most cell types, it is present in the cytoplasm of the CCAP neurons and certain other cells, which suggests that the protein might execute two different RNA‐binding functions. Lark protein exhibits significant circadian changes in abundance in at least one group of CCAP neurons, with abundance being lowest during the night, several hours prior to the time of adult ecdysis. Such a temporal profile is consistent with genetic evidence indicating that the protein serves a repressor function in mediating the clock regulation of adult ecdysis. In contrast, we did not observe circadian changes in CCAP neuropeptide abundance in late pupae, although CCAP amounts were decreased in newly‐emerged adults, presumably because the peptide is released at the time of ecdysis. Given the cytoplasmic localization of the lark RNA‐binding protein within CCAP neurons, and the known role of CCAP in the control of ecdysis, we suggest that changes in lark abundance may regulate the translation of a factor important for CCAP release or CCAP cell excitability. © 2000 John Wiley & Sons, Inc. J Neurobiol 45: 14–29, 2000 http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Developmental Neurobiology Wiley

Circadian regulation of the lark RNA‐binding protein within identifiable neurosecretory cells

Download PDF
16 pages

Loading next page...
 
/lp/wiley/circadian-regulation-of-the-lark-rna-binding-protein-within-OAmNf9JMby

References (47)

Publisher
Wiley
Copyright
Copyright © 2000 Wiley Subscription Services, Inc., A Wiley Company
ISSN
1932-8451
eISSN
1932-846X
DOI
10.1002/1097-4695(200010)45:1<14::AID-NEU2>3.0.CO;2-X
Publisher site
See Article on Publisher Site

Abstract

Molecular genetic analysis indicates that rhythmic changes in the abundance of the Drosophila lark RNA‐binding protein are important for circadian regulation of adult eclosion (the emergence or ecdysis of the adult from the pupal case). To define the tissues and cell types that might be important for lark function, we have characterized the spatial and developmental patterns of lark protein expression. Using immunocytochemical or protein blotting methods, lark can be detected in late embryos and throughout postembryonic development, from the third instar larval stage to adulthood. At the late pupal (pharate adult) stage, lark protein has a broad pattern of tissue expression, which includes two groups of crustacean cardioactive peptide (CCAP)‐containing neurons within the ventral nervous system. In other insects, the homologous neurons have been implicated in the physiological regulation of ecdysis. Whereas lark has a nuclear distribution in most cell types, it is present in the cytoplasm of the CCAP neurons and certain other cells, which suggests that the protein might execute two different RNA‐binding functions. Lark protein exhibits significant circadian changes in abundance in at least one group of CCAP neurons, with abundance being lowest during the night, several hours prior to the time of adult ecdysis. Such a temporal profile is consistent with genetic evidence indicating that the protein serves a repressor function in mediating the clock regulation of adult ecdysis. In contrast, we did not observe circadian changes in CCAP neuropeptide abundance in late pupae, although CCAP amounts were decreased in newly‐emerged adults, presumably because the peptide is released at the time of ecdysis. Given the cytoplasmic localization of the lark RNA‐binding protein within CCAP neurons, and the known role of CCAP in the control of ecdysis, we suggest that changes in lark abundance may regulate the translation of a factor important for CCAP release or CCAP cell excitability. © 2000 John Wiley & Sons, Inc. J Neurobiol 45: 14–29, 2000

Journal

Developmental Neurobiology – Wiley

Published: Oct 1, 2000

Keywords: ; ; ; ;

There are no references for this article.