Molecular endocrinological study on reproduction in amphioxus

l.自然条件下文昌鱼生境的环境生态研究，了解文昌鱼的繁殖现象(l) 1997年8月至2000年7月在潭井maru进行的调查，包括生长、划分和环境因素分析，以及ROV对文昌鱼生境的观察。繁殖和产卵的成功在实验室和分析游泳和生殖行为。(1) 1999年秋季至2000年夏季在实验室饲养的雌雄文昌鱼的性腺发育情况。(2) 2000年7月产卵受精成功，幼虫生长3周。(3)除黑暗条件外，产卵日期与环境条件无相关性。(4)雌性和雄性之间发出开始产卵的生理信号的可能性，通过对雌雄分开进行的生殖活动进行试验。(5)光、聚光灯、振动、触摸等刺激引起的方向不同的逃逸反应。触碰尾部会导致向尾部逃逸，触碰头部会导致向尾部或头部逃逸。哈切克窝与基因(1)神经索向哈切克窝延伸的发现，这似乎与下丘脑或正中隆起相对应。(2)文昌鱼存在脑-下丘脑-垂体系统的可能性。(3)利用Hatsceck’s pit和muscle之间的相减法构建cDNA文库，得到的cDNA克隆约有50种，在cDNA序列数据库中检索同源序列。与内分泌系统有关的功能蛋白有胰岛素样肽、IGF结合蛋白、抑制素等，但没有编码垂体激素基因的克隆。(4)获得的克隆首先在成虫和幼虫上进行原位杂交。

l. Environmental and ecological study on amphioxus habitat for understanding reproductive phenomena under natural condition(l) Investigations including analysis of growth, division and environmental factors, and observation of habitat by using ROV in Tansei-Maru from August, 1997 to July, 2000.2. Success of breeding and spawning in laboratories and analysis of swimming and reproductive behaviors.(1) Gonadal developments in a female and a male amphioxi bred from autumn in 1999 to summer in 2000 in lab. (2) Success of spawning and fertilization in July in 2000 and growth of larva for three weeks. (3) No correlation between spawning date and environmental conditions except for the requirement of dark condition. (4) A possibility of physiological signal between female and male for starting spawning which is experimented by a loose of a reproductive activity in each sex which kept separately. (5) Different escape reaction in the direction that caused by stimulation of light, spot light, vibration or touch. Touch at tail causes an escape direction to tail, and touch at head causes to either tail or head.3. Hatschek's pit and the gene(l) Discover of the elongation of nerve cord toward Hatscheck's pit which seems to correspond to hypothalamus or median eminence. (2) Possibility of an existence of brain-hypothalamus-pituitary system in amphioxus. (3) cDNA clones from cDNA library constructed from subtraction between Hatsceck's pit and muscle contained approximately 50 kinds of clones which homologous sequences are searched in data base of cDNA sequence. Functional protein concerned with endocrine system areinsulin-like peptide, IGF binding protein, inhibin and so on but mo clones encoded pituitary hormone genes. (4) Expression of obtained clones start by using in situ hybridization on adult and larva.