Disruption of a Neuropeptide Gene, flp-1 , Causes Multiple Behavioral Defects in Caenorhabditis elegans

Abstract

Neuropeptides serve as important signaling molecules in the nervous system. The FMRFamide (Phe-Met-Arg-Phe-amide)-related neuropeptide gene family in the nematode Caenorhabditis elegans is composed of at least 18 genes that may encode 53 distinct FMRFamide-related peptides. Disruption of one of these genes, flp-1, causes numerous behavioral defects, including uncoordination, hyperactivity, and insensitivity to high osmolarity. Conversely, overexpression of flp-1 results in the reciprocal phenotypes. On the basis of epistasis analysis, flp-1 gene products appear to signal upstream of a G protein-coupled second messenger system. These results demonstrate that varying the levels of FLP-1 neuropeptides can profoundly affect behavior and that members of this large neuropeptide gene family are not functionally redundant in C. elegans.

The Robustness ofCaenorhabditis elegansMale Mating Behavior Depends on the Distributed Properties of Ray Sensory Neurons and Their Output through Core and Male-Specific Targets

“…Their role appears to be modulatory because their absence reduces the response robustness, but not induction, of B-neuron-induced tail curling. In the hermaphrodite, serotonin and FMRF-amides have complex neuromodulatory effects on several worm motor behaviors, including egg laying and locomotion (Nelson et al, 1998;Rogers et al, 2006;Hapiak et al, 2009).…”

Behavioral plasticity in C. elegans: Paradigms, circuits, genes

“…A reverse genetic approach was required to retrieve the first mutant in a neuropeptide gene, the flp-1 gene, which is predicted to encode several FMRFamide related peptides (Nelson et al, 1998). flp-1 mutants lay eggs irrespective of the presence or absence of food, and have thus decoupled the sensory input from the motor output (Waggoner et al, 1998).…”

“…Two sensory neurons that appear to be redundantly required for the food-mediated modulation of egg laying, AWC and ASK (Sawin, 1996), both synapse onto the AIA interneuron class. Because AIA is one of the relatively limited sets of head neurons in which the promoter of the flp-1 gene is active (Nelson et al, 1998), it is tempting to speculate that the AIA interneuron responds to either of its two presynaptic partners by releasing FMRFamide(s), which then act either directly or indirectly on the egg-laying muscles. The hyperactive locomotory phenotype observed in flp-1 mutant animals is also indicative of defects in the response to food, and suggests that flp-1 encoded peptides are, like serotonin, widely used to signal the feeding status of the worm.…”

Collective Excitations of a Trapped Bose-Einstein Condensate in the Presence of a 1D Optical Lattice

“…Many results have been reported e.g. interference of atomic de Broglie waves tunneling from a vertical array of BECs [9], observation of squeezed states in a BEC [10], realization of a linear array of Josephson junctions [11] with BECs, observation of Bloch oscillations [12] and culminating with the observation of the quantum phase transition from a superfluid to a Mott insulator [13]. Recently, the general interest of this field has been extended to a careful study of the loading of BECs in an optical lattice [14] and to the observation of collapse and revival of the matter wave field of a BEC [15].…”