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排序方式: 共有75条查询结果,搜索用时 31 毫秒
1.
猪原始生殖嵴细胞(PGCs)建系因素的研究 总被引:4,自引:3,他引:4
从五指山猪(WSZP)近交系第8~13代培育群中,先后选用21头5~10月龄青年母猪,分别于授精后25~30d采集胎儿106个,进行原始生殖嵴(PGCs)细胞分离、培养等建系技术研究。以DMEM F10(1:1)为基础培养液,按添加或不添加生长因子,将培养液分为A、B、C3种,并以STO细胞作饲养层,在38℃、5.0%CO2和湿润的气相中进行培养建系。结果获得胚胎生殖嵴细胞(EG)细胞系6个细胞株,其中1个EG细胞株传至11代、2个传至5代、1个传至4代、2个传至3代冻存。并进行了AKP染色、体外分化、冷冻-解冻复苏和嵌合体制作等鉴定研究。研究发现:不同胚龄对EG细胞建系具有一定影响,不同培养液对EG细胞建系效果不同,STO细胞饲养层的质量是建株、传代、冷冻-解冻复苏的关键因素之一。EG细胞系的初步建立,为今后筛选进入种系的EG细胞系、实施体外基因操作提供了可能。 相似文献
2.
Birds obtained by embryo engineering are used to study embryo development and to produce transgenic birds. As this method of producing birds still generate strong emotions of the public opinion head ornaments, testes and semen characteristics of sex chimera roosters were examined to check whether they differ from chickens obtained by non‐manipulated methods. Measurements of head ornaments, testes and semen were correlated with each other. Semen quality factor (SQF) was calculated, as well as the level of fluctuating asymmetry (FA) of bilateral traits (wattles and testes). Positive correlation was found for comb width and wattle length and comb thickness and sperm concentration. Semen characteristics and FA did not exceed the level encounter in other chicken lines. Results obtained indicate that germline chimeras are similar in appearance of secondary sexual traits, and semen and testes characteristics to chickens produced in non‐manipulated way. 相似文献
3.
Suzu Sakao Takafumi Fujimoto Terumasa Kobayashi Goro Yoshizaki Etsuro Yamaha Katsutoshi Arai 《Fisheries Science》2009,75(4):993-1000
Diploid gametes generated with tetraploid animals are a stepping stone to improving chromosome manipulation techniques. However,
artificially induced tetraploid individuals generally die soon after hatching. Diploid gametes could be induced by in vivo
cultures of tetraploid primordial germ cells (PGCs) through germ-line chimera. In the present study, characteristics of PGCs
were studied in inviable tetraploid masu salmon, Oncorhynchus masou. Histological observation of tetraploid embryos revealed that the same or smaller numbers of PGCs were observed and they
migrate into the genital ridges as did diploid PGCs during gonadogenesis. By whole-mount in situ hybridization using vasa messenger RNA (mRNA), 4–35 vasa-positive signals were detected in a pair of genital ridges of tetraploids. By cytological
observation of genital ridge cell suspensions, several large round cells were observed, some of which extended pseudopodia.
They also contained large nuclei and round granules in their cytoplasm, characteristics of PGCs. As the results suggest that
inviable artificial tetraploids have PGCs, we expect to achieve diploid gamete production through surrogate propagation and
tetraploid fish production. 相似文献
4.
以嫁接嵌合体红江橙为材料,在扫描电镜上观察了红江橙及其分离出来的4种变异类型的叶、果表面及其切面的结构.结果表明,红江橙的叶面与其分离出来的黄肉果和橘变果有较大差异,红江橙果皮切面海绵层介于黄肉果与橘变果之间,而从果皮的切面发现表皮层的细胞排列紧密,体积较小,呈长形方格状,与紧接其下的海绵层具有较大的、圆形蜂窝状的细胞明显可分.作为同质体的黄肉果和橘变果,则未能观察到这种结构差异 相似文献
5.
Because of the role of the meristem in plant growth and reproduction, somatic mutations in plants have long been suspected of conferring herbivore and pathogen resistance on individual plants and, in the case of trees, individual branches within single plants. A few instances of resistance to phytophagous insects owing to somatic mutations have been reported in the literature. More recently, a striking example has demonstrated how somatic mutations confer resistance to an herbicide on an invasive plant, Hydrilla verticillata. The array of new methods for manipulating genomes (e.g., gene‐editing) plus existing examples of somatic mutation‐associated resistance suggest that such mutations might be useful in silviculture, agriculture, and horticulture. Answering several general questions about somatic mutations in plants would facilitate such applications: Why are so few examples reported? Do other cases exist but go undetected for want of adequate attention or methods? Under what circumstances do somatic mutations enter gametophytes? © 2018 Society of Chemical Industry 相似文献
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8.
Summary Thornless Loganberry (TL) is a periclinal chimeral blackberry in which a layer of mutant (thornless) epidermis surrounds a core of wild-type (thorny) tiusse. Due to its chimeral arrangement, TL produces thorny adventitious root cuttings and thorny offspring. To separate the chimera into its components parts, meristems of TL were grow in vitro on modified Murashige and Skoog medium to yield callus and adventitious shoots. One of these shoots has survived, flowered, and produced thornless offspring from seed. The importance of this non-chimeral TL is discussed.List of terms BA
6-benzylaminopurine
- GA3
gibberellic acid
- NAA
naphthalene acetic acid
- hybridberry
polyploid bramble interspecific hybrids
- MS
Murashige & Skoog (1962) high mineral salt medium
- TL
Thornless Loganberry
- TLtc
tissue culture-derived (non-chimeral) Thornless Loganberry 相似文献
9.
以“早蜜橙”这个新发现的柑桔嫁接嵌合体及与其有关品种类型的柑桔为材料,通过叶片气孔观察、花粉试验、多种酶同工酶分析和果实性状的比较分析,研究了它的来源、结构和果实主要经济性状的表现.结果发现:(1)在来源上,“早蜜橙”是由甜橙(新会甜橙的可能性最大)和南丰蜜桔形成的嫁接嵌合体.(2)在嵌合体结构上,“早蜜橙”是一个不完全周缘嵌合体,LI、LII以橙为主,LI则以桔为主,兼有橙因子.(3)“早蜜橙”果实品质上等,果实性状大部分来自橙,少数来自桔.糖、酸等主要营养物质的含量大都介于两亲本之间,绝大部分水解氨基酸含量比原接穗和砧木品种都高,有较大的利用价值. 相似文献
10.
Hiroshi KAGAMI Jun YASUDA Takahiro TAGAMI Mitsuru NAITO Yuko MATSUBARA Takashi HARUMI Takamasa NOGUCHI Yasuhiro YAMAMOTO Taikai TAKAHASHI Junichi MATSUYAMA Hiroyuki KOMATSU Tamao ONO 《Animal Science Journal》2002,73(6):453-456
Effect of the strain combination of the donor and recipient on production efficiency of W‐bearing sperm in mixed‐sex chimeric testes was analyzed. The combinations of the donors and recipients were White Leghorn (WL) and Rhode Island Red (RIR), and vice versa. Generated mixed‐sex chimeras that had the male phenotype at sexual maturity were classified into four groups: (1) a female WL donor and a male RIR recipient; (2) a male WL donor and a female RIR recipient; (3) a female RIR donor and a male WL recipient; (4) a male RIR donor and a female WL recipient. The mean number of W‐bearing sperm detected by in situ hybridization among 10 000 sperm observed were 147, 165, 30 and 45 in groups 1, 2, 3 and 4, respectively. The numbers in groups 1 and 2 were both significantly higher than those of groups 3 and 4 (P < 0.05). The combination of a WL donor and a RIR recipient produced W‐bearing sperm more efficiently than the reverse combination. 相似文献