title: Regulation of seasonal reproduction by hypothalamic activation of thyroid hormone.
abstract: Organisms living outside the tropics measure the changes in the length of the day to adapt to seasonal changes in the environment. Animals that breed during spring and summer are called long-day breeders, while those that breed during fall are called short-day breeders. Although the influence of thyroid hormone in the regulation of seasonal reproduction has been known for several decades, its precise mechanism remained unknown. Recent studies revealed that the activation of thyroid hormone within the mediobasal hypothalamus plays a key role in this phenomenon. This localized activation of the thyroid hormone is controlled by thyrotropin (thyroid-stimulating hormone) secreted from the pars tuberalis of the pituitary gland. Although seasonal reproduction is a rate-limiting factor in animal production, genes involved in photoperiodic signal transduction pathway could emerge as potential targets to facilitate domestication.
authors.affiliation: Division of Seasonal Biology, National Institute for Basic Biology , Okazaki , Japan.
authors.forename: Ai
authors.initials: A
authors.lastname: Shinomiya
authors.affiliation: Division of Seasonal Biology, National Institute for Basic Biology , Okazaki , Japan ; Laboratory of Animal Physiology, Graduate School of Bioagricultural Sciences, Nagoya University , Nagoya , Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Shimmura
authors.affiliation: Laboratory of Animal Physiology, Graduate School of Bioagricultural Sciences, Nagoya University , Nagoya , Japan ; Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University , Nagoya , Japan ; Avian Bioscience Research Center, Graduate School of Bioagricultural Sciences, Nagoya University , Nagoya , Japan.
authors.forename: Taeko
authors.initials: T
authors.lastname: Nishiwaki-Ohkawa
authors.affiliation: Division of Seasonal Biology, National Institute for Basic Biology , Okazaki , Japan ; Laboratory of Animal Physiology, Graduate School of Bioagricultural Sciences, Nagoya University , Nagoya , Japan ; Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University , Nagoya , Japan ; Avian Bioscience Research Center, Graduate School of Bioagricultural Sciences, Nagoya University , Nagoya , Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshimura
keywords: ependymal cell; iodothyronine deiodinase; mediobasal hypothalamus; pars tuberalis; seasonal reproduction; thyroid hormone; thyrotropin