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牙鲆精子的超显微结构 总被引:11,自引:3,他引:8
不同种类的硬骨鱼,其精子的超显微结构也各不相同[1~3]。牙鲆是我国一种重要海产鱼类,本实验对其精子的超显微结构进行了观察,并与其他鱼类精子的超显微结构进行了比较。1 材料与方法实验中所用的雄性牙鲆亲鱼取自中国科学院海洋研究所水族楼亲鱼饲养池。取性腺发育成熟的亲鱼,用人工挤压的方法,将精液挤压入干燥、洁净的玻璃器皿中,然后加入三倍体积2.5%戊二醛磷酸缓冲液中(pH4.7),混合均匀,以4000r/min离心5min,弃去上清液,沉淀包埋于甘油明胶中。包埋块再置于2.5%戊二醛中,4℃过夜。1%… 相似文献
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众所周知,提取高纯度和完整的RNA是开展鱼类胚胎发育分子生物学的前提。据Sambrook,J.等1989年,Chomczynski,P.等1987年报道,分离动物细胞质的总RNA主要是在强变性试剂,如:盐酸胍、异硫氰酸胍,或在含有蛋白酶K的缓冲溶液中,通过匀浆细胞来分离和提取细胞质的总RNA。用这类方法提取的总RNA往往受少量DNA的污染,可能在构建cDNA文库和反转录聚合酶链式反应中引起混乱。用无RNA酶的DNA酶处理提取的总RNA也不是十分理想的方法,为克服以上方法的缺陷,本文在已有的鱼类胚… 相似文献
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MyoD,Myf5,and myogenin are myogenic regulatory factors that play important roles during myogenesis.It is thought that MyoD and Myf5 are required for myogenic determination,while myogenin is important for terminal differentiation and lineage maintenance.To better understand the function of myogenic regulatory factors in muscle development of flounder,an important economic fish in Asia,real-time quantitative RT-PCR was used to characterize the expression patterns of MyoD,Myf5, and myogenin at early stages of embryo development,and in different tissues of the adult flounder.The results show that,Myf5 is the first gene to be expressed during the early stages of flounder development, followed by MyoD and myogenin.The expressions of Myf5,MyoD,and myogenin at the early stages have a common characteristic:expression gradually increased to a peak level,and then gradually decreased to an extremely low level.In the adult flounder,the expression of the three genes in muscle is much higher than that in other tissues,indicating that they are important for muscle growth and maintenance of grown fish.During embryonic stages,the expression level of MyoD might serve an important role in the balance between muscle cell differentiation and proliferation.When the MyoD expression is over 30%of its highest level,the muscle cells enter the differentiation stage. 相似文献
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转鲑鱼生长激素基因酵母菌发酵特性的研究 总被引:2,自引:1,他引:1
张培军、Ball等研究表明,外源性生长激素通过注射或浸泡的方法可加快鱼的生长[1]。根据Mclean1987年、Shunsuke等1993年研究发现鱼类后肠具有吸收部分生长激素进入血液循环的特点,本研究室将鲑鱼生长激素基因克隆进无毒无害的酵母菌中,利用可控制的诱导条件,培养出含鲑鱼生长激素的酵母菌,直接掺入饵料,使生长激素通过消化道吸收,以促进鱼的生长。Jacqueline等1989年指出,由于携带外源基因的酵母菌与普通酵母菌的培养要求不同,既要促使菌体快速生长又要保证外源基因的表达,本研究的目的在于选择适宜的培养条件,实现转基因酵母菌的高密度培… 相似文献
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人工诱导雌核发育牙鲆的染色体及核型证明 总被引:6,自引:1,他引:5
于1994-1996年,分别在威海海洋渔业捕捞公司(石岛)和鸿洋实业总公司龙须岛育苗场采集人工培育的3-5龄牙鲆亲鱼,采用紫外线照射法使牙鲆精子遗传物质失活,并用冷休克法抑制受精卵第二极体释放,从而获得雌核发育二倍体牙好。原肠期采用空气干燥法、Giemsa染色,得到雌核发育二倍体、正常二倍体及单倍体的染色体制片,进行染色体和核型的分析。结果表明,牙鲆的雌核发育二倍体和正常二倍体的染色体数均为2n=48,核型为48t,即48条端部着色点染色体,臂数NF=48,两者的核型设有明显差异;单倍体为24条端部着丝点染色体;在3个组别中,第一号染色体上都有一明显的次缢痕。雌核发育二倍体牙鲆的诱导率为98%。 相似文献
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环境因子对牙鲆精子运动能力的影响 总被引:8,自引:1,他引:7
于1997年5-6月,在山东荣成市石岛养殖场采用挤压法收集牙鲆亲鱼的精子,利用显微镜观察精子的活力,研究外界环境因子的变化对牙鲆精子运动能力的影响。结果表明,将蔗糖、NaCl、KCl、MgCl2、CaCl2等溶解于去离子水中,制成不同浓度即具有不同渗透压的溶液,不同渗透压的溶液对精子运动的诱导结果不同。EDTANa2溶液不能诱导精子运动。在人工海水中加入一定量的EDTANa2后,可使原先运动的精子静止;在该溶液中加入新的Ca2 后,将不再诱导原来受到EDTANa2抑制的精子。如用MgSO4代替溶液中的CaCl2,可诱导精子运动;而当用MgCl2代替溶液中的CaCl2,以及用CaCl2或NaCl代替MgSO4时,溶液即失去诱导精子运动的能力。在pH=4.0-9、5的海水中,牙解精子均可正常运动。 相似文献
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Proteins of the DYRK (dual-specificity tyrosine-phosphorylation-regulated kinase) family are characterized by the presence
of a conserved kinase domain and N-terminal DH box. DYRK2 is involved in regulating key developmental and cellular processes, such as neurogenesis, cell proliferation, cytokinesis,
and cellular differentiation. Herein, we report that the ortholog of DYRK2 found in zebrafish shares about 70% identity with that of human, mouse, and chick. RT-PCR showed that DYRK2 is expressed maternally and zygotically. In-situ hybridization results show that DYRK2 is expressed in somite cells that will develop into muscles. Our results provide preliminary evidence for investigating the
in-vivo function of DYRK2 in zebrafish muscle development. 相似文献
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