TY  - JOUR
A1  - Chen, Jiangtian
A1  - Reiher, Wencke
A1  - Hermann-Luibl, Christiane
A1  - Sellami, Azza
A1  - Cognigni, Paola
A1  - Kondo, Shu
A1  - Helfrich-Förster, Charlotte
A1  - Veenstra, Jan A.
A1  - Wegener, Christian
T1  - Allatostatin A Signalling in Drosophila Regulates Feeding and Sleep and Is Modulated by PDF
JF  - PLoS Genetics
N2  - Feeding and sleep are fundamental behaviours with significant interconnections and cross-modulations. The circadian system and peptidergic signals are important components of this modulation, but still little is known about the mechanisms and networks by which they interact to regulate feeding and sleep. We show that specific thermogenetic activation of peptidergic Allatostatin A (AstA)-expressing PLP neurons and enteroendocrine cells reduces feeding and promotes sleep in the fruit fly Drosophila. The effects of AstA cell activation are mediated by AstA peptides with receptors homolog to galanin receptors subserving similar and apparently conserved functions in vertebrates. We further identify the PLP neurons as a downstream target of the neuropeptide pigment-dispersing factor (PDF), an output factor of the circadian clock. PLP neurons are contacted by PDF-expressing clock neurons, and express a functional PDF receptor demonstrated by cAMP imaging. Silencing of AstA signalling and continuous input to AstA cells by tethered PDF changes the sleep/activity ratio in opposite directions but does not affect rhythmicity. Taken together, our results suggest that pleiotropic AstA signalling by a distinct neuronal and enteroendocrine AstA cell subset adapts the fly to a digestive energy-saving state which can be modulated by PDF.
KW  - neurons
KW  - neuroimaging
KW  - circadian rhythms
KW  - food consumption
KW  - sleep
KW  - biological locomotion
KW  - Drosophila melanogaster
KW  - signal peptides
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-178170
VL  - 12
IS  - 9
ER  - 
TY  - JOUR
A1  - Harrington, John M.
A1  - Scelsi, Chris
A1  - Hartel, Andreas
A1  - Jones, Nicola G.
A1  - Engstler, Markus
A1  - Capewell, Paul
A1  - MacLeod, Annette
A1  - Hajduk, Stephen
T1  - Novel African Trypanocidal Agents: Membrane Rigidifying Peptides
JF  - PLoS One
N2  - The bloodstream developmental forms of pathogenic African trypanosomes are uniquely susceptible to killing by small hydrophobic peptides. Trypanocidal activity is conferred by peptide hydrophobicity and charge distribution and results from increased rigidity of the plasma membrane. Structural analysis of lipid-associated peptide suggests a mechanism of phospholipid clamping in which an internal hydrophobic bulge anchors the peptide in the membrane and positively charged moieties at the termini coordinate phosphates of the polar lipid headgroups. This mechanism reveals a necessary phenotype in bloodstream form African trypanosomes, high membrane fluidity, and we suggest that targeting the plasma membrane lipid bilayer as a whole may be a novel strategy for the development of new pharmaceutical agents. Additionally, the peptides we have described may be valuable tools for probing the biosynthetic machinery responsible for the unique composition and characteristics of African trypanosome plasma membranes.
KW  - depth
KW  - trypanosome lytic factor
KW  - signal peptides
KW  - cell surface
KW  - protein
KW  - brucei
KW  - environment
KW  - bilayers
KW  - binding
KW  - probes
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-135179
VL  - 7
IS  - 9
ER  -