小鼠四倍体半克隆胚胎发育研究

半克隆(Semi-Cloned)胚胎是通过注射体细胞核到未去核的卵母细胞中产生的。在半克隆胚胎中,体细胞被用来作为精子的替代物。然而,由于异常的染色体分离,构建的半克隆胚胎在激活后形成了非整倍体而导致胚胎发育受到严重影响,不能发育到期。本研究通过抑制小鼠半克隆胚胎在激活过程中染色体数目减半,避免非整倍体胚胎形成,研究四倍体半克隆(TetraploidSemi-cloned,TSC)胚胎的发育和体细胞核的掺入对胚胎发育的影响。结果显示,TSC胚胎的体外发育率显著高于二倍体半克隆胚胎,与正常受精卵及孤雌激活对照无显著性差异,但TSC胚胎的细胞数在桑椹胚和囊胚期比正常二倍体受精胚胎和孤雌激活胚胎少。通过Oct-4染色发现,TSC胚胎囊胚期内细胞团(InnerCellMass,ICM)细胞很少或者没有。移植63个四倍体半克隆胚胎到3只假孕母鼠体内,得到20个胎盘,但没有得到胎儿。组蛋白乙酰化和DNA甲基化检测显示,部分TSC胚胎在囊胚期没有形成正常受精胚胎在ICM和滋养外胚层(Trophectoderm,TE)之间的差异分布。TSC胚胎的基因表达不依赖于细胞分裂次数而依赖于发育时间。虽然TSC胚胎避免了二倍体半克隆胚胎形成非整倍体现象,但由于TSC胚胎没有ICM细胞或ICM细胞很少,所以只能形成胎盘而不能形成胎儿。本实验第一次较为全面地研究了TSC胚胎的发育,同时也为研究体细胞核再程序化、基因打靶技术提供了一种新的途径。     

秋水仙素诱导越橘四倍体研究

用秋水仙素浸渍法及培养基添加法对南高丛越橘组培苗"3#"进行了四倍体诱导,结果表明:浸渍法诱变效果优于培养基添加法,获得的变异株系多为嵌合体,0.1%的秋水仙素茎尖浸泡24h为最佳诱变组合,存活率为70%,变异率为13.33%,四倍体植株率为6.67%.通过对茎、叶、气孔、保卫细胞、染色体数目以及叶绿素含量等形态生理指标的检测,证明四倍体较二倍体发生了显著变化.     

Induction of gynogenesis in red crucian carp using spermatozoa of blunt snout bream

Gynogenetic diploid was induced in red crucian carp (RCC) ( Carassius auratus Red Variety) eggs using UV-irradiated spermatozoa from blunt snout bream (B) (Megalobrama amblycephaia) or from mirror carp (C) (Cyprinus carpio. L) . Spermatozoa were genetically inactivated by an appropriate UV dosage, and then the maternal DNA was duplicated with cold shock at 0-4℃. When using the spermatozoa of B, the fertilization rate, hatching rate and survival at first feeding were 52. 6±3. 0 %, 23.6±4.1 % and15.7±3.4 % , respectively, and the survival at first feeding was significantly higher than that (11.3±2.2%) when using the spermatozoa of C (Cyprinus carpio. L). According to the morphological characteristics, the chromosome number and the degree of gonadal development, gynogenetic RCC could be distinguished from the control hybrids of RCC♀×B♂. The individuals with red body color, 100 chromosomes and normal gonadal development were successful gynogenetic RCC, while the individuals with 124 or 148 chromosomes and delayed gonadal development were hybrids of (RCC×B). The triploid hybrids (RCC×B) (2 years old) were sterile, but the tetraploid hybrids (RCC×B) were sexually mature age of two. In the present study, compared to the spermatozoa of C, the advantages of spermatozoa of B as the activation source were that could increase the survival at first feeding of gynogenetic individuals and simplify the confirmation of gynogenetic status, which suggested that the sperm of B was an effective activation source for inducing gynogenesis in crucian carp.     

Induction of gynogenesis in red crucian carp using spermatozoa of blunt snout bream

Gynogenetic diploid was induced in red crucian carp (RCC) (Carassius auratus Red Variety) eggs using UV-irradiated spermatozoa from blunt snout bream (B) (Megalobrama amblycephala) or from mirror carp (C) (Cyprinus carpio. L). Spermatozoa were genetically inactivated by an appropriate UV dosage, and then the maternal DNA was duplicated with cold shock at 0-4℃. When using the spermatozoa of B, the fertilization rate, hatching rate and survival at first feeding were 52.6±3.0 %, 23.6±4.1 % and 15.7±3.4 %, respectively, and the survival at first feeding was significantly higher than that (11.3±2.2%) when using the spermatozoa of C (Cyprinus carpio. L). According to the morphological characteristics, the chromosome number and the degree of gonadal development, gynogenetic RCC could be distinguished from the control hybrids of RCC♀× B♂. The individuals with red body color, 100 chromosomes and normal gonadal development were successful gynogenetic RCC, while the individuals with 124 or 148 chromosomes and delayed gonadal development were hybrids of (RCC× B). The triploid hybrids (RCC× B) (2 years old) were sterile, but the tetraploid hybrids (RCC× B) were sexually mature age of two. In the present study, compared to the spermatozoa of C, the advantages of spermatozoa of B as the activation source were that could increase the survival at first feeding of gynogenetic individuals and simplify the confirmation of gynogenetic status, which suggested that the sperm of B was an effective activation source for inducing gynogenesis in crucian carp.     

水稻光温敏不育系培矮64s二倍体与四倍体颖花性状和剑叶性状的比较

对水稻光温敏不育系培矮64s二倍体和四倍体的颖花和剑叶性状进行了比较研究。结果表明，培矮64s四倍体的颖壳长、颖壳宽、花药长、花药宽、柱头长、柱头宽和剑叶夹角等性状都较二倍体显增大；剑叶长和剑叶宽显减小。相关分析表明，倍性对性状间相关性的影响主要表现在量上，即影响相关性的程度，对相关性的性质影响较小。     

玫瑰香葡萄二倍体与四倍体的三种生化指标比较研究

对二倍体玫瑰香与加倍后形成的四倍体变异品系的５种器官，分别测定了过氧化物酶活性、多酚氧化酶活性和酚类物质含量。试验结果表明，二倍体玫瑰香品种加倍形成四倍体后，雄蕊、雌蕊和成叶的过氧化物酶活性均极显著降低；雄蕊和雌蕊的多酚氧化酶活性、酚类物质含量也极显著地降低，但成叶和叶柄的多酚氧化酶活性、酚类物质含量却极显著地升高，上述３种生化指标在茎尖上均未表现出差异     

四倍体天山雪莲组培苗倍性分析比较

采用形态学,气孔,染色体分析方法,并与二倍体相比较,对四倍体天山雪莲组培苗倍性进行分析。有利于探索其在形态学,细胞水平,以及染色体等方面的变化,为其进一步开发利用奠定基础。     

Effects of different nuclear recipients on developmental potential of mouse somatic nuclear transfer embryos

Somatic cell nuclear transfer has been succeeded in procedures of nuclear transfer. One is single nucleartransfer, the other is serial nuclear transfer. Viable animals have been cloned in different species using both me-thods[1—6]. Different nuclear recipients and donors wereused in serial nuclear transfer, namely, transferring thenuclear of reconstructed embryo into enucleated MⅡoocytes[7], transferring the nuclear of reconstructed em-bryos at one cell stage into enucleated zygote[4] and t…