Aufsatz in einer Fachzeitschrift
Circadian pacemaker coupling by multi-peptidergic neurons in the cockroach Leucophaea maderae



Details zur Publikation
Autor(inn)en:
Soehler, S.; Stengl, M.; Reischig, T.
Publikationsjahr:
2011
Zeitschrift:
Cell and Tissue Research
Seitenbereich:
559-577
Jahrgang/Band:
343:
Erste Seite:
559
Letzte Seite:
577
ISSN:
0302-766X

Zusammenfassung, Abstract
Lesion and transplantation studies in the cockroach, Leucophaea maderae, have located its bilaterally symmetric circadian pacemakers necessary for driving circadian locomotor activity rhythms to the accessory medulla of the optic lobes. The accessory medulla comprises a network of peptidergic neurons, including pigment-dispersing factor (PDF)-expressing presumptive circadian pacemaker cells. At least three of the PDF-expressing neurons directly connect the two accessory medullae, apparently as a circadian coupling pathway. Here, the PDF-expressing circadian coupling pathways were examined for peptide colocalization by tracer experiments and double-label immunohistochemistry with antisera against PDF, FMRFamide, and Asn(13)-orcokinin. A fourth group of contralaterally projecting medulla neurons was identified, additional to the three known groups. Group one of the contralaterally projecting medulla neurons contained up to four PDF-expressing cells. Of these, three medium-sized PDF-immunoreactive neurons coexpressed FMRFamide and Asn(13)-orcokinin immunoreactivity. However, the contralaterally projecting largest PDF neuron showed no further peptide colocalization, as was also the case for the other large PDF-expressing medulla cells, allowing the easy identification of this cell group. Although two-thirds of all PDF-expressing medulla neurons coexpressed FMRFamide and orcokinin immunoreactivity in their somata, colocalization of PDF and FMRFamide immunoreactivity was observed in only a few termination sites. Colocalization of PDF and orcokinin immunoreactivity was never observed in any of the terminals or optic commissures. We suggest that circadian pacemaker cells employ axonal peptide sorting to phase-control physiological processes at specific times of the day.


Schlagwörter
Accessory medulla, Circadian rhythms, Cockroach, FMRFamide, Leucophaea maderae (Insects), Orcokinin, Pigment-dispersing hormone


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Zuletzt aktualisiert 2019-25-07 um 17:27