Sukhan Zahid Parvez, Kitano Hajime, Selvaraj Sethu, Yoneda Michio, Yamaguchi Akihiko, Matsuyama Michiya
1 Laboratory of Marine Biology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan.
Zoolog Sci. 2013 Dec;30(12):1081-91. doi: 10.2108/zsj.30.1081.
To gain a better understanding of the reproductive endocrinology of a primitive order clupeiform fish (Japanese anchovy, Engraulis japonicus), cDNAs encoding three gonadotropin-releasing hormone (GnRH) isoforms were isolated from the brain, and their distribution was analyzed using insitu hybridization (ISH). The three GnRH isoforms include GnRH1 (herring GnRH), GnRH2 (chicken GnRH-ll) and GnRH3 (salmon GnRH), and their full-length cDNAs encode 88, 86, and 89 deduced amino acids (aa), respectively. Alignment analysis of Japanese anchovy GnRH isoforms showed lower identities with other teleost fish. The major population of GnRH1 neurons was localized in the ventral telencephalon (VT) and nucleus preopticus (NPO) of the preoptic area (POA) with minor population in the anterior olfactory bulb (OB). GnRH2 neurons were restricted to the midbrain tegmentum (MT), specific to the nucleus of the medial longitudinal fasciculus (nMLF). GnRH3 neurons were localized in the olfactory nerve (ON), ventral OB, and transitional area between OB and ON. Interestingly, GnRH1 neurons were also localized in the olfactory bulb, in addition to its major population in the preoptic area. These results indicate the differential distribution of three GnRH isoforms expressed in the brain of the Japanese anchovy.
为了更好地理解一种原始硬骨鱼目鱼类（日本鳀鱼，Engraulis japonicus）的生殖内分泌学，从其大脑中分离出编码三种促性腺激素释放激素（GnRH）亚型的cDNA，并使用原位杂交（ISH）分析它们的分布。这三种GnRH亚型包括GnRH1（鲱鱼GnRH）、GnRH2（鸡GnRH-II）和GnRH3（鲑鱼GnRH），它们的全长cDNA分别编码88、86和89个推导氨基酸（aa）。日本鳀鱼GnRH亚型的比对分析显示与其他硬骨鱼类的同源性较低。GnRH1神经元的主要群体位于视前区（POA）的腹侧端脑（VT）和视前核（NPO），在前嗅球（OB）中有少量群体。GnRH2神经元局限于中脑被盖（MT），特定于内侧纵束核（nMLF）。GnRH3神经元位于嗅神经（ON）、腹侧OB以及OB和ON之间的过渡区域。有趣的是，除了在视前区的主要群体外，GnRH1神经元也位于嗅球中。这些结果表明日本鳀鱼大脑中三种GnRH亚型的分布存在差异。
