春天一到就知道該求偶繁衍后代的動物，是如何察覺季節(jié)更替的呢,？日本名古屋大學(xué)的研究人員，在２０日出版的英國《自然》雜志上發(fā)表研究報告指出,，某些動物體內(nèi)的甲狀腺促進素ＴＳＨ會隨著日照時間開始拉長而增加分泌,，同時刺激腦部發(fā)出“春來了”的訊息，所以ＴＳＨ也可說是生物的“報春荷爾蒙”,。
ＴＳＨ向來以調(diào)節(jié)體溫或代謝功能而廣為人知,，這是首次有研究證實ＴＳＨ對于腦部所產(chǎn)生的影響,。此外，繼去年春天有其他研究人員發(fā)現(xiàn)促使植物開花的荷爾蒙后,，這是首次成功發(fā)現(xiàn)提醒動物“春天到了”的荷爾蒙,。
吉村崇對此表示：“下一步的課題便是弄清制造ＴＳＨ的基因啟動機制。若能運用相關(guān)研究成果,，拉長動物繁殖期,，便可能有助于增加畜產(chǎn)量。”此外,，該成果也可能會用在容易在特定季節(jié)發(fā)病的憂郁癥等方面的研究,。
生物谷推薦原始出處：
Nature 452, 317-322 (20 March 2008) | doi:10.1038/nature06738; Received 22 July 2007; Accepted 25 January 2008
Thyrotrophin in the pars tuberalis triggers photoperiodic response
Nobuhiro Nakao1,11, Hiroko Ono1,11, Takashi Yamamura1, Tsubasa Anraku1, Tsuyoshi Takagi1, Kumiko Higashi1, Shinobu Yasuo1, Yasuhiro Katou1, Saburo Kageyama1, Yumiko Uno1, Takeya Kasukawa2, Masayuki Iigo3, Peter J. Sharp4, Atsushi Iwasawa5, Yutaka Suzuki6, Sumio Sugano6, Teruyuki Niimi7, Makoto Mizutani8, Takao Namikawa8, Shizufumi Ebihara1,8, Hiroki R. Ueda2,9 & Takashi Yoshimura1,8,10
Division of Biomodelling, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
Functional Genomics Subunit, Centre for Developmental Biology, RIKEN, 2-3-3 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
Department of Applied Biochemistry, Faculty of Agriculture, Utsunomiya University, 350 Mine-machi, Utsunomiya, 321-8505, Japan
Division of Genetics and Genomics, Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian EH25 9PS, UK
Laboratory of Comparative Biochemistry, Graduate School of Applied Biological Sciences, Gifu University, Gifu 501-1193, Japan
Department of Medical Genome Sciences, Graduate School of Frontier Sciences, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
Division of Biofunctions Development, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
Avian Bioscience Research Centre, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
Laboratory for Systems Biology, Centre for Developmental Biology, RIKEN, 2-3-3 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
These authors contributed equally to this work.
Correspondence to: Takashi Yoshimura1,8,10 Correspondence and requests for materials should be addressed to T.Yo. (Email: [email protected]).
Abstract
Molecular mechanisms regulating animal seasonal breeding in response to changing photoperiod are not well understood. Rapid induction of gene expression of thyroid-hormone-activating enzyme (type 2 deiodinase, DIO2) in the mediobasal hypothalamus (MBH) of the Japanese quail (Coturnix japonica) is the earliest event yet recorded in the photoperiodic signal transduction pathway. Here we show cascades of gene expression in the quail MBH associated with the initiation of photoinduced secretion of luteinizing hormone. We identified two waves of gene expression. The first was initiated about 14 h after dawn of the first long day and included increased thyrotrophin (TSH) -subunit expression in the pars tuberalis; the second occurred approximately 4 h later and included increased expression of DIO2. Intracerebroventricular (ICV) administration of TSH to short-day quail stimulated gonadal growth and expression of DIO2 which was shown to be mediated through a TSH receptor–cyclic AMP (cAMP) signalling pathway. Increased TSH in the pars tuberalis therefore seems to trigger long-day photoinduced seasonal breeding.
