研究者詳細 - 吉村　崇

Thyroid hormone and seasonal regulation of reproduction 招待有り査読有り

Yoshimura Takashi

FRONTIERS IN NEUROENDOCRINOLOGY 34 巻 ( 3 ) 頁： 157 - 166 2013年8月

出版者・発行元：Frontiers in Neuroendocrinology

Organisms living outside the tropics use changes in photoperiod to adapt to seasonal changes in the environment. Several models have contributed to an understanding of this mechanism at the molecular and endocrine levels. Subtropical birds are excellent models for the study of these mechanisms because of their rapid and dramatic response to changes in photoperiod. Studies of birds have demonstrated that light is perceived by a deep brain photoreceptor and long day-induced thyrotropin (TSH) from the pars tuberalis (PT) of the pituitary gland causes local thyroid hormone activation within the mediobasal hypothalamus (MBH). The locally generated bioactive thyroid hormone, T3, regulates seasonal gonadotropin-releasing hormone (GnRH) secretion, and hence gonadotropin secretion. In mammals, the eyes are the only photoreceptor involved in photoperiodic time perception and nocturnal melatonin secretion provides an endocrine signal of photoperiod to the PT to regulate TSH. Here, I review the current understanding of the hypothalamic mechanisms controlling seasonal reproduction in mammals and birds. © 2013 Elsevier Inc.

DOI： 10.1016/j.yfrne.2013.04.002

Seasonal Time Measurement During Reproduction 査読有り

Ikegami Keisuke, Yoshimura Takashi

JOURNAL OF REPRODUCTION AND DEVELOPMENT 59 巻 ( 4 ) 頁： 327 - 333 2013年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Reproduction and Development

Most species living outside the tropical zone undergo physiological adaptations to seasonal environmental changes and changing day length (photoperiod); this phenomenon is called photoperiodism. It is well known that the circadian clock is involved in the regulation of photoperiodism such as seasonal reproduction, but the mechanism underlying circadian clock regulation of photoperiodism remains unclear. Recent molecular analysis have revealed that, in mammals and birds, the pars tuberalis (PT) of the pituitary gland acts as the relay point from light receptors, which receive information about the photoperiod, to the endocrine responses. Long-day (LD)-induced thyroid-stimulating hormone (TSH) in the PT acts as a master regulator of seasonal reproduction in the ependymal cells (ECs) within the mediobasal hypothalamus (MBH) and activates thyroid hormone (TH) by inducing the expression of type 2 deiodinase in both LD and short-day (SD) breeding animals. Furthermore, the circadian clock has been found to be localized in the PT and ECs as well as in the circadian pacemaker(s). This review purposes to summarize the current knowledge concerning the involvement of the neuroendocrine system and circadian clock in seasonal reproduction. © 2013 by the Society for Reproduction and Development.

DOI： 10.1262/jrd.2013-035

The saccus vasculosus of fish is a sensor of seasonal changes in day length

Nakane Yusuke, Ikegami Keisuke, Iigo Masayuki, Ono Hiroko, Takeda Korenori, Takahashi Daisuke, Uesaka Maiko, Kimijima Meita, Hashimoto Ramu, Arai Natsumi, Suga Takuya, Kosuge Katsuya, Abe Tomotaka, Maeda Ryosuke, Senga Takumi, Amiya Noriko, Azuma Teruo, Amano Masafumi, Abe Hideki, Yamamoto Naoyuki, Yoshimura Takashi

NATURE COMMUNICATIONS 4 巻 2013年7月

Next-generation sequencing reveals genomic features in the Japanese quail 査読有り

Kawahara-Miki Ryouka, Sano Satoshi, Nunome Mitsuo, Shimmura Tsuyoshi, Kuwayama Takehito, Takahashi Shinji, Kawashima Takaharu, Matsuda Yoichi, Yoshimura Takashi, Kono Tomohiro

GENOMICS 101 巻 ( 6 ) 頁： 345 - 353 2013年6月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Genomics

The Japanese quail has several advantages as a laboratory animal for biological and biomedical investigations. In this study, the draft genome of the Japanese quail was sequenced and assembled using next-generation sequencing technology. To improve the quality of the assembly, the sequence reads from the Japanese quail were aligned against the reference genome of the chicken. The final draft assembly consisted of 1.75. Gbp with an N50 contig length of 11,409. bp. On the basis of the draft genome sequence obtained, we developed 100 microsatellite markers and used these markers to evaluate the genetic variability and diversity of 11 lines of Japanese quail. Furthermore, we identified Japanese quail orthologs of spermatogenesis markers and analyzed their expression using in situ hybridization. The Japanese quail genome sequence obtained in the present study could enhance the value of this species as a model animal. © 2013 Elsevier Inc.

DOI： 10.1016/j.ygeno.2013.03.006

その他リンク： http://orcid.org/0000-0003-2072-8851

Circadian clock determines the timing of rooster crowing 査読有り

Shimmura Tsuyoshi, Yoshimura Takashi

CURRENT BIOLOGY 23 巻 ( 6 ) 頁： R231 - R233 2013年3月

Circadian Clock Gene <i>Per2</i> Is Not Necessary for the Photoperiodic Response in Mice 査読有り国際誌

Ikegami Keisuke, Iigo Masayuki, Yoshimura Takashi

PLOS ONE 8 巻 ( 3 ) 頁： e58482 2013年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：PLoS ONE

In mammals, light information received by the eyes is transmitted to the pineal gland via the circadian pacemaker, i.e., the suprachiasmatic nucleus (SCN). Melatonin secreted by the pineal gland at night decodes night length and regulates seasonal physiology and behavior. Melatonin regulates the expression of the β-subunit of thyroid-stimulating hormone (TSH; Tshb) in the pars tuberalis (PT) of the pituitary gland. Long day-induced PT TSH acts on ependymal cells in the mediobasal hypothalamus to induce the expression of type 2 deiodinase (Dio2) and reduce type 3 deiodinase (Dio3) that are thyroid hormone-activating and hormone-inactivating enzymes, respectively. The long day-activated thyroid hormone T3 regulates seasonal gonadotropin-releasing hormone secretion. It is well established that the circadian clock is involved in the regulation of photoperiodism. However, the involvement of the circadian clock gene in photoperiodism regulation remains unclear. Although mice are generally considered non-seasonal animals, it was recently demonstrated that mice are a good model for the study of photoperiodism. In the present study, therefore, we examined the effect of changing day length in Per2 deletion mutant mice that show shorter wheel-running rhythms under constant darkness followed by arhythmicity. Although the amplitude of clock gene (Per1, Cry1) expression was greatly attenuated in the SCN, the expression profile of arylalkylamine N-acetyltransferase, a rate-limiting melatonin synthesis enzyme, was unaffected in the pineal gland, and robust photoperiodic responses of the Tshb, Dio2, and Dio3 genes were observed. These results suggested that the Per2 clock gene is not necessary for the photoperiodic response in mice. © 2013 Ikegami et al.

DOI： 10.1371/journal.pone.0058482

Understanding mechanism of seasonal reproduction and deep brain photoreceptor

新規光受容器「オプシン5」欠損マウスの行動解析

太田航, 中根右介, 池上啓介, 吉村崇

日本畜産学会大会講演要旨集 116回巻頁： 97 - 97 2013年3月

脊椎動物の光周性の制御機構招待有り

頼永恵理子, 吉村崇

生物科学 64 巻頁： 205 - 211 2013年

脊椎動物が季節を感知する仕組みの解明招待有り査読有り

前田遼介, 吉村崇

トレーサー 54 巻頁： 3 - 8 2013年

哺乳類における新規光受容器Opsin 5の発現解析

太田航, 中根右介, 池上啓介, 吉村崇

日本畜産学会大会講演要旨集 115回巻頁： 216 - 216 2012年3月

Circadian clocks and the measurement of daylength in seasonal reproduction

Ikegami Keisuke, Yoshimura Takashi

MOLECULAR AND CELLULAR ENDOCRINOLOGY 349 巻 ( 1 ) 頁： 76 - 81 2012年2月

Nakane Y., Yoshimura T.

Seikagaku 83 巻 ( 2 ) 頁： 114 - 117 2011年12月

脊椎動物の光周性

太田航, 吉村崇

バイオメカニズム学会誌 35 巻 ( 4 ) 頁： 251 - 257 2011年11月

記述言語：日本語出版者・発行元：バイオメカニズム学会

四季の存在する地域に棲む動物は，季節の変化に応じて行動や生理機能を変えることで環境の変化に適応している．このとき動物たちは日照時間（光周期）を季節の指標としているため，このような性質は光周性と呼ばれる．ウズラやマウスを用いた最近の研究により，脊椎動物における光周性の制御機構が徐々に明らかとなりつつある．本稿では光周性研究の歴史から，我々の研究によって明らかとなった動物が「春」を感じるしくみ，及び光周性制御に重要な光情報を感知している「脳深部光受容器」の発見までを概説し，光情報をもとに引き起こされる動物の巧みな生存戦略を紹介する．

DOI： 10.3951/sobim.35.251

CiNii Books

Progesterone Is a Sperm-Releasing Factor from the Sperm-Storage Tubules in Birds

Ito Tomomi, Yoshizaki Norio, Tokumoto Toshinobu, Ono Hiroko, Yoshimura Takashi, Tsukada Akira, Kansaku Norio, Sasanami Tomohiro

ENDOCRINOLOGY 152 巻 ( 10 ) 頁： 3952 - 3962 2011年10月

ウズラの季節性精巣退縮機構の解明

渥美優介, 池上啓介, 小野ひろ子, 村山至, 中根右介, 太田航, 新井菜津美, 手賀明倫, 飯郷雅之, 吉田松生, 吉村崇

The Journal of Reproduction and Development 57 巻 ( Suppl. ) 頁： j103 - j103 2011年8月

Opsin 5 as a deep brain photoreceptor regulating photoperiodism

Nakane Yusuke, Ikegami Keisuke, Ono Hiroko, Yamamoto Naoyuki, Yoshida Shosei, Kamei Yasuhiro, Higashi Sho-ichi, Hirunagi Kanjun, Ebihara Shizufumi, Kubo Yoshihiro, Yoshimura Takashi

NEUROSCIENCE RESEARCH 71 巻頁： E171 - E171 2011年

Oocytic expression of zona pellucida protein ZP4 in Japanese quail (<i>Coturnix japonica</i>)

Serizawa Mami, Kinoshita Mihoko, Rodler Daniela, Tsukada Akira, Ono Hiroko, Yoshimura Takashi, Kansaku Norio, Sasanami Tomohiro

ANIMAL SCIENCE JOURNAL 82 巻 ( 2 ) 頁： 227 - 235 2011年

出版者・発行元：Animal Science Journal

The avian perivitelline layer, an extracellular matrix homologous to the zona pellucida (ZP) of mammalian oocytes, is composed mainly by zona pellucida gene family glycoproteins. Our previous studies in Japanese quail have demonstrated that the matrix's components, ZP3 and ZPD, are synthesized in ovarian granulosa cells. Another component, ZP1, is synthesized in the liver. Recently, we demonstrated that another minor constituent, ZP2 is produced in the oocytes of the immature follicles. In the present study, we report the isolation of complementary DNA encoding quail ZP4 and its expression and origin in the female birds. By ribonuclease protection assay and in situ hybridization, we demonstrated that ZP4 transcripts were transcribed in the oocytes of small white follicles. The expression level of ZP4 decreased dramatically during follicular development, and the highest expression was observed in the small white follicles. Western blot analysis using the specific antibody against ZP4 indicated that the immunoreactive 58.2kDa protein was present in the lysates of the small white follicles. These results demonstrate for the first time that the avian ZP4 is expressed in the oocyte, and that the expression pattern of the gene is similar to that of ZP2. © 2011 The Authors. Journal compilation © 2011 Japanese Society of Animal Science.

DOI： 10.1111/j.1740-0929.2010.00830.x