title: RNA interference of gonadotropin-inhibitory hormone gene induces arousal in songbirds.
abstract: Gonadotropin-inhibitory hormone (GnIH) was originally identified in quail as a hypothalamic neuropeptide inhibitor of pituitary gonadotropin synthesis and release. However, GnIH neuronal fibers do not only terminate in the median eminence to control anterior pituitary function but also extend widely in the brain, suggesting it has multiple roles in the regulation of behavior. To identify the role of GnIH neurons in the regulation of behavior, we investigated the effect of RNA interference (RNAi) of the GnIH gene on the behavior of white-crowned sparrows, a highly social songbird species. Administration of small interfering RNA against GnIH precursor mRNA into the third ventricle of male and female birds reduced resting time, spontaneous production of complex vocalizations, and stimulated brief agonistic vocalizations. GnIH RNAi further enhanced song production of short duration in male birds when they were challenged by playbacks of novel male songs. These behaviors resembled those of breeding birds during territorial defense. The overall results suggest that GnIH gene silencing induces arousal. In addition, the activities of male and female birds were negatively correlated with GnIH mRNA expression in the paraventricular nucleus. Density of GnIH neuronal fibers in the ventral tegmental area was decreased by GnIH RNAi treatment in female birds, and the number of gonadotropin-releasing hormone neurons that received close appositions of GnIH neuronal fiber terminals was negatively correlated with the activity of male birds. In summary, GnIH may decrease arousal level resulting in the inhibition of specific motivated behavior such as in reproductive contexts.
authors.affiliation: Department of Integrative Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, California, United States of America. t.ubuka@aoni.waseda.jp
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ubuka
authors.forename: Motoko
authors.initials: M
authors.lastname: Mukai
authors.forename: Jordan
authors.initials: J
authors.lastname: Wolfe
authors.forename: Ryan
authors.initials: R
authors.lastname: Beverly
authors.forename: Sarah
authors.initials: S
authors.lastname: Clegg
authors.forename: Ariel
authors.initials: A
authors.lastname: Wang
authors.forename: Serena
authors.initials: S
authors.lastname: Hsia
authors.forename: Molly
authors.initials: M
authors.lastname: Li
authors.forename: Jesse S
authors.initials: JS
authors.lastname: Krause
authors.forename: Takanobu
authors.initials: T
authors.lastname: Mizuno
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Fukuda
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Tsutsui
authors.forename: George E
authors.initials: GE
authors.lastname: Bentley
authors.forename: John C
authors.initials: JC
authors.lastname: Wingfield
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001143:Arousal / Q000235:genetics* / Q000502:physiology; D030161:Avian Proteins / Q000235:genetics* / Q000378:metabolism; D001921:Brain / Q000166:cytology / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D007028:Hypothalamic Hormones / Q000235:genetics* / Q000378:metabolism; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009474:Neurons / Q000378:metabolism; D034622:RNA Interference; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D020308:Songbirds; D013739:Testosterone / Q000097:blood; D014828:Vocalization, Animal / Q000502:physiology
chemical_list: D030161:Avian Proteins; D007028:Hypothalamic Hormones; D012322:RNA Precursors; D013739:Testosterone