Abstract
In order to adapt to seasonal changes, animals exhibit robust changes in their reproductive status, body weight, and molt. However, the molecular mechanisms regulating such seasonal changes in physiology and behavior are not fully understood. Here, we report the photoperiodic regulation of the insulin receptor (IR) gene in the infundibular nucleus (anatomically homologous to the mammalian arcuate nucleus) of the Japanese quail. When the birds were transferred from short-day to long-day conditions, a significant increase in the level of IR mRNA was observed on the 10th long day, whereas that in testicular length was observed on the 5th long day. Castration abolished IR mRNA expression induced by long-day conditions, whereas the testosterone administration mimicked induction of IR mRNA expression induced by long-day conditions. These results suggested that the photoperiodic regulation of the IR mRNA in the infundibular nucleus is mediated by testosterone from the testes. It has been known that the central administration of insulin increases luteinizing hormone (LH) secretion, and neuron-specific disruption of IR gene causes impaired gonadal function due to the dysregulation of LH and increased food intake and body weight. Together with these results, the photoperiodic regulation of the IR mRNA in the hypothalamus may enhance the effect of long days in the seasonal response of reproduction and body weight changes.
| Original language | English |
|---|---|
| Pages (from-to) | 86-90 |
| Number of pages | 5 |
| Journal | Brain Research |
| Volume | 1163 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - Aug 13 2007 |
| Externally published | Yes |
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All Science Journal Classification (ASJC) codes
- Neuroscience(all)
- Molecular Biology
- Clinical Neurology
- Developmental Biology
Cite this
Photoperiodic changes in hypothalamic insulin receptor gene expression are regulated by gonadal testosterone. / Anraku, Tsubasa; Takagi, Tsuyoshi; Nakao, Nobuhiro; Watanabe, Miwa; Yasuo, Shinobu; Katou, Yasuhiro; Ueda, Yukihiro; Murai, Atsushi; Iigo, Masayuki; Ebihara, Shizufumi; Yoshimura, Takashi.
In: Brain Research, Vol. 1163, No. 1, 13.08.2007, p. 86-90.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Photoperiodic changes in hypothalamic insulin receptor gene expression are regulated by gonadal testosterone
AU - Anraku, Tsubasa
AU - Takagi, Tsuyoshi
AU - Nakao, Nobuhiro
AU - Watanabe, Miwa
AU - Yasuo, Shinobu
AU - Katou, Yasuhiro
AU - Ueda, Yukihiro
AU - Murai, Atsushi
AU - Iigo, Masayuki
AU - Ebihara, Shizufumi
AU - Yoshimura, Takashi
PY - 2007/8/13
Y1 - 2007/8/13
N2 - In order to adapt to seasonal changes, animals exhibit robust changes in their reproductive status, body weight, and molt. However, the molecular mechanisms regulating such seasonal changes in physiology and behavior are not fully understood. Here, we report the photoperiodic regulation of the insulin receptor (IR) gene in the infundibular nucleus (anatomically homologous to the mammalian arcuate nucleus) of the Japanese quail. When the birds were transferred from short-day to long-day conditions, a significant increase in the level of IR mRNA was observed on the 10th long day, whereas that in testicular length was observed on the 5th long day. Castration abolished IR mRNA expression induced by long-day conditions, whereas the testosterone administration mimicked induction of IR mRNA expression induced by long-day conditions. These results suggested that the photoperiodic regulation of the IR mRNA in the infundibular nucleus is mediated by testosterone from the testes. It has been known that the central administration of insulin increases luteinizing hormone (LH) secretion, and neuron-specific disruption of IR gene causes impaired gonadal function due to the dysregulation of LH and increased food intake and body weight. Together with these results, the photoperiodic regulation of the IR mRNA in the hypothalamus may enhance the effect of long days in the seasonal response of reproduction and body weight changes.
AB - In order to adapt to seasonal changes, animals exhibit robust changes in their reproductive status, body weight, and molt. However, the molecular mechanisms regulating such seasonal changes in physiology and behavior are not fully understood. Here, we report the photoperiodic regulation of the insulin receptor (IR) gene in the infundibular nucleus (anatomically homologous to the mammalian arcuate nucleus) of the Japanese quail. When the birds were transferred from short-day to long-day conditions, a significant increase in the level of IR mRNA was observed on the 10th long day, whereas that in testicular length was observed on the 5th long day. Castration abolished IR mRNA expression induced by long-day conditions, whereas the testosterone administration mimicked induction of IR mRNA expression induced by long-day conditions. These results suggested that the photoperiodic regulation of the IR mRNA in the infundibular nucleus is mediated by testosterone from the testes. It has been known that the central administration of insulin increases luteinizing hormone (LH) secretion, and neuron-specific disruption of IR gene causes impaired gonadal function due to the dysregulation of LH and increased food intake and body weight. Together with these results, the photoperiodic regulation of the IR mRNA in the hypothalamus may enhance the effect of long days in the seasonal response of reproduction and body weight changes.
UR - http://www.scopus.com/inward/record.url?scp=34547153392&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34547153392&partnerID=8YFLogxK
U2 - 10.1016/j.brainres.2007.06.028
DO - 10.1016/j.brainres.2007.06.028
M3 - Article
C2 - 17618942
AN - SCOPUS:34547153392
VL - 1163
SP - 86
EP - 90
JO - Brain Research
JF - Brain Research
SN - 0006-8993
IS - 1
ER -