斑马鱼性腺发育的组织学观察  

Histological Observation of Zebrafish Gonad Development

作　　者：王晶[1] 王冰[1] 李纪同[1] 杨磊[1] 张永忠[1] 

机构地区：[1]聊城大学生命科学学院,聊城252059

出　　处：《基因组学与应用生物学》2011年第2期168-174,共7页Genomics and Applied Biology

基　　金：山东省自然科学基金(Y2007D06);国家自然科学基金(31071268)共同资助

摘　　要：在过去几十年,斑马鱼(Danio rerio)由于其发育周期短且速度快,胚胎发育透明,已经成为众多研究领域的典型模式生物。斑马鱼的性腺发育和分化非常特殊,雄性和雌性幼鱼的性腺在早期全部发育成"类卵巢"结构。目前,对于斑马鱼的性别分化和性腺分化机制还不清楚。本文以孵化后不同时期的斑马鱼仔鱼和幼鱼的生殖腺为材料,经石蜡切片和苏木精染色后,荧光显微镜下观察了斑马鱼仔鱼性腺从出现、分化到成熟的发育过程。结果发现:孵化后5～10日龄仔鱼腹腔两侧可以观察到没有分化的生殖腺,其中的生殖细胞明显比周围的体细胞大;孵化后14～24日龄仔鱼的生殖腺中可见由卵原细胞分裂形成的生殖包囊,其中的生殖细胞进一步分化、分裂形成体积更大、数量更多的卵母细胞;25日龄左右的仔鱼,其性腺成为在腹腔两侧对称,而且在组织结构上也较为典型的卵巢样结构。到35日龄前后可见一部分仔鱼的性腺逐步由卵巢样结构向精巢结构转变的过程。我们在2周左右的仔鱼的性腺中观察到了生殖包囊存在,这一现象还未见有前人报道。在本试验中,我们不仅清楚地观察到类似卵巢的性腺中"卵母细胞"逐渐凋亡消失的过程,还观察到性腺由最初的类似卵巢样结构逐渐变成典型的精巢结构的整个过程。这些研究成果将为发育生物学提供有价值的信息和第一手资料。Over the past few decades,zebrafish （Danio rerio） has become a typical model species for several research areas,primarily due to its short generation time and rapid,transparent embryonic development.Zebrafish gonad development and differentiation are rather special for that in both of early male and female juveniles the gonad develop into overy-like-structure （＇juvenile ovary＇）.The sexual differentiation mechanism of zebrafish is far from being fully understood at present.In this study,juvenile zebrafish gonad developmental process from the earliest recognizable stage,through differentiation,to maturation,was observed under fluorescent microscope after hematoxylin staining.The results showed that undifferentiated gonads could be observed on both sides of dorsal abdominal cavity of 5～10 days＇ juveniles,in which germ cells were significantly bigger than the surrounding somatic cells;germline cysts derived from oogonium division could be seen in the gonads of 14～24 days＇ juveniles,in which the germ cells further differentiated and increased both in number and in size.Gonads from about 25 days＇ juveniles developed into typical symmetic localization and typical ovary-like in shape and histological structure.From about 35 days,gonads in some juveniles revealed clear transformation process from ovary-like shape and histological structure into testises.We identified the occurrence of the germline cyst in the gonads of juvenile zebrafish 2 weeks post-hatching,to our konwledge,this phenomenon has not been reported previously.In this study we both clearly observed the apoptotic process of ＂oocyte＂ in the ovary-like gonads,untill all the ＂oocytes＂ disapear gradually,and the whole process of morphological changes of the gonad from the overy-like-structure to typical testis gradually.These observations will provide valuable information and firsthand materials to the the developmental biology.

关 键 词：斑马鱼 性腺发育 石蜡切片 生殖包囊 组织学观察 

分 类 号：S917.4[农业科学—水产科学]