RRC ID 56874
著者 Ikegami K, Yoshimura T.
タイトル Circadian clocks and the measurement of daylength in seasonal reproduction.
ジャーナル Mol Cell Endocrinol
Abstract Temperate zone organisms measure changes in daylength to adapt to seasonal changes in their environment. Recent studies have revealed that the long day (LD)-induced thyrotropin (TSH) in the pars tuberalis (PT) of the pituitary gland act as a master factor regulating seasonal reproduction on the the ependymal cells (ECs) within the mediobasal hypothalamus (MBH) to induce expression of type 2 deiodinase (Dio2), a thyroid hormone (TH)-activating enzyme in both LD and short day (SD) breeders. Locally activated TH in the MBH is believed to trigger GnRH secretion from the hypothalamus in LD breeders, while it terminates reproductive activity in SD breeders. Circadian clock is involved in seasonal time measurement and clock genes are expressed in the PT and ECs. Although circadian and melatonin-dependent control of TSH appears to link the circadian clock and the photoperiodic response in mammals, how this circadian clock measure daylength remains to be clarified.
巻・号 349(1)
ページ 76-81
公開日 2012-2-5
DOI 10.1016/j.mce.2011.06.040
PII S0303-7207(11)00373-X
PMID 21767603
MeSH Animals Circadian Clocks* Circadian Rhythm Melatonin / metabolism Photoperiod* Reproduction* Seasons* Suprachiasmatic Nucleus / metabolism Suprachiasmatic Nucleus / physiology Thyroid Hormones / metabolism Thyrotropin / metabolism
IF 3.693
引用数 39
リソース情報
ニワトリ・ウズラ