TY - JOUR
T1 - Anatomical and genotype-specific mechanosensory responses in Drosophila melanogaster larvae
AU - Titlow, Josh S.
AU - Rice, Jordan
AU - Majeed, Zana R.
AU - Holsopple, Emily
AU - Biecker, Stephanie
AU - Cooper, Robin L.
N1 - Publisher Copyright:
© 2014 Elsevier Ireland Ltd and the Japan Neuroscience Society.
PY - 2014/6/1
Y1 - 2014/6/1
N2 - Afferent neurons commonly exhibit a somatotopic arrangement in the central nervous system that organizes spatially discrete sensory input. We are interested in how that spatial input gets integrated into motor commands. With resources for screening genes and neural circuits, and given that the cells and ion channels that transduce tactile stimuli in Drosophila larvae are remarkably well-characterized, larval mechanosensation is an ideal system for investigating how specific behaviors emerge from localized sensory input. We observed that crawling larvae are more reactive to a 20. mN tactile stimulus on the head than on the tail or abdomen. Behavioral responses that were evoked by the stimuli also depended on where the stimulus was delivered. Differences in relative sensitivity were observed in different genotypes, e.g., a null white mutant and hypomorphic smn mutant are significantly more reactive to tail touches than Canton-S larvae. Responses were inhibited by silencing chemical transmission in a combination of multidendritic and chordotonal neurons, but not by inhibiting any specific subset of neurons. Extracellular recordings from segmental nerves revealed that sensory-evoked responses exhibit spike-timing dependence at the neural circuit level. Tactile stimuli reduced endogenous firing frequency and increased bursting periods when applied during periods of motor activity. The same stimulus initiated bursts of activity when applied during inactive periods. Together, these data depict the spatial and temporal complexity of mechanosensation as it applies to action selection, and provide a foundation for addressing how neural circuits in the CNS adjust their activity to afferent input.
AB - Afferent neurons commonly exhibit a somatotopic arrangement in the central nervous system that organizes spatially discrete sensory input. We are interested in how that spatial input gets integrated into motor commands. With resources for screening genes and neural circuits, and given that the cells and ion channels that transduce tactile stimuli in Drosophila larvae are remarkably well-characterized, larval mechanosensation is an ideal system for investigating how specific behaviors emerge from localized sensory input. We observed that crawling larvae are more reactive to a 20. mN tactile stimulus on the head than on the tail or abdomen. Behavioral responses that were evoked by the stimuli also depended on where the stimulus was delivered. Differences in relative sensitivity were observed in different genotypes, e.g., a null white mutant and hypomorphic smn mutant are significantly more reactive to tail touches than Canton-S larvae. Responses were inhibited by silencing chemical transmission in a combination of multidendritic and chordotonal neurons, but not by inhibiting any specific subset of neurons. Extracellular recordings from segmental nerves revealed that sensory-evoked responses exhibit spike-timing dependence at the neural circuit level. Tactile stimuli reduced endogenous firing frequency and increased bursting periods when applied during periods of motor activity. The same stimulus initiated bursts of activity when applied during inactive periods. Together, these data depict the spatial and temporal complexity of mechanosensation as it applies to action selection, and provide a foundation for addressing how neural circuits in the CNS adjust their activity to afferent input.
KW - Behavior
KW - Crawling
KW - Drosophila melanogaster larva
KW - Electrophysiology
KW - Mechanosensory
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UR - http://www.scopus.com/inward/citedby.url?scp=84907986012&partnerID=8YFLogxK
U2 - 10.1016/j.neures.2014.04.003
DO - 10.1016/j.neures.2014.04.003
M3 - Article
C2 - 24768745
AN - SCOPUS:84907986012
SN - 0168-0102
VL - 83
SP - 54
EP - 63
JO - Neuroscience Research
JF - Neuroscience Research
ER -