近年来发现人类多种神经肌肉疾病存在线粒体电子传递链(electron transport chain,ETC)缺陷[1-7].由于线粒体在遗传上受核基因和线粒体基因双重控制,给确定ETC缺陷的来源造成困难.转线粒体DNA技术是线粒体同无线粒体DNA的细胞(ρ0cells...近年来发现人类多种神经肌肉疾病存在线粒体电子传递链(electron transport chain,ETC)缺陷[1-7].由于线粒体在遗传上受核基因和线粒体基因双重控制,给确定ETC缺陷的来源造成困难.转线粒体DNA技术是线粒体同无线粒体DNA的细胞(ρ0cells)融合[8,9],形成转线粒体DNA细胞系(mtDNA-transferted cell line,也称cytoplasmic hy-brids,简称cybrids),使病人的线粒体DNA(mito-chondrial DNA,mtDNA)同正常人的mtDNA在完全一致的细胞背景中表达,排除细胞内其它因素的干扰,单独研究mtDNA对细胞功能的影响.展开更多
New lines of wheat ( Triticum aestivum L.) was obtained by introducing the DNA of sorghum (Sorghum vulgare Pers.) into wheat cultivar 'Longchun 13'. The changes of respiratory pathway, contents of protein, Na+...New lines of wheat ( Triticum aestivum L.) was obtained by introducing the DNA of sorghum (Sorghum vulgare Pers.) into wheat cultivar 'Longchun 13'. The changes of respiratory pathway, contents of protein, Na+ and K+ in the leaves and roots of the new lines of wheat under salt stress were determined and compared with the control cultivar, 'Longchun 13'. The decrease of the content of K+ was observed with the increase of NaCl concentrations, but the decrease was more in the control than that in the new lines, and more in roots than in leaves. Content of proline and Na+ in both two wheats lines increased greatly, but the former increased more significantly in the new lines and the latter more significantly in control both in leaves and roots. The operation of the cyanide-resistant pathway of respiration was enhanced at different degrees after salt stress and it increased much more in roots and leaves of the control plant than that in the new lines, but the cytochrome pathway of electron transport was still the main one consistently. The possible significance of these changes was discussed.展开更多
Transgenic animal technology has been one of the fastest growing biotechnology areas. The exogenous genes have been introduced into the animal genome by genetic engineering, so that these genes can be inherited and ex...Transgenic animal technology has been one of the fastest growing biotechnology areas. The exogenous genes have been introduced into the animal genome by genetic engineering, so that these genes can be inherited and expressed by offspring to produce desired traits or evaluate function in elite livestock breeds. There are several methodologies for the production of transgenic animals, i.e., （1） microinjection of genes into pronuclei of fertilized ova; （2） DNA transfer by retroviruses; （3） injection of embryonic germ （EG）/embryonic stem （ES） cells previously treated with foreign DNA; （4） DNA transfer into cells and embryos with using liposomes; （5） exogenous DNA transfer while in vitro fertilization by using sperm; （6） electroporation of DNA into sperm, embryos or ova; （7） biolistics; （8） nuclear transfer （NT） with somatic cells, EG or ES cells; （9） germ line stem cell-mediated; （10） gene targeting; （! 1） gene silencing technology with RNA interference; （12） induced pluripotent stem cell; （13） zinc-finger nuclease gene targeting technology. Gene farming is one of the newest and most promising areas in modern biotechnology. Cattle, goats, sheep, pigs and rabbits are the main farm livestock species and fish is also used in transgenic technology. The question of ＂why make transgenic animals？＂ is very important. Some of the answers to this question are： （1） to obtain new knowledge; （2） to solve the genetic code; （3） to create genetic disease models; （4） to study the genetic control of physiological systems; （5） to improve animal production traits; （6） to produce new animal products. Transgenic technology is one of the main and important tools in the finding solutions to problems of growing population with their applications to different organisms, and takes more attention and interest every day. Transgenic technology creates opportunities and areas to play with organisms to fulfill the demands of people. Because of this, this paper based on mainly transgenic applications to take people＇s attention and exhibit its importance.展开更多
文摘New lines of wheat ( Triticum aestivum L.) was obtained by introducing the DNA of sorghum (Sorghum vulgare Pers.) into wheat cultivar 'Longchun 13'. The changes of respiratory pathway, contents of protein, Na+ and K+ in the leaves and roots of the new lines of wheat under salt stress were determined and compared with the control cultivar, 'Longchun 13'. The decrease of the content of K+ was observed with the increase of NaCl concentrations, but the decrease was more in the control than that in the new lines, and more in roots than in leaves. Content of proline and Na+ in both two wheats lines increased greatly, but the former increased more significantly in the new lines and the latter more significantly in control both in leaves and roots. The operation of the cyanide-resistant pathway of respiration was enhanced at different degrees after salt stress and it increased much more in roots and leaves of the control plant than that in the new lines, but the cytochrome pathway of electron transport was still the main one consistently. The possible significance of these changes was discussed.
文摘Transgenic animal technology has been one of the fastest growing biotechnology areas. The exogenous genes have been introduced into the animal genome by genetic engineering, so that these genes can be inherited and expressed by offspring to produce desired traits or evaluate function in elite livestock breeds. There are several methodologies for the production of transgenic animals, i.e., （1） microinjection of genes into pronuclei of fertilized ova; （2） DNA transfer by retroviruses; （3） injection of embryonic germ （EG）/embryonic stem （ES） cells previously treated with foreign DNA; （4） DNA transfer into cells and embryos with using liposomes; （5） exogenous DNA transfer while in vitro fertilization by using sperm; （6） electroporation of DNA into sperm, embryos or ova; （7） biolistics; （8） nuclear transfer （NT） with somatic cells, EG or ES cells; （9） germ line stem cell-mediated; （10） gene targeting; （! 1） gene silencing technology with RNA interference; （12） induced pluripotent stem cell; （13） zinc-finger nuclease gene targeting technology. Gene farming is one of the newest and most promising areas in modern biotechnology. Cattle, goats, sheep, pigs and rabbits are the main farm livestock species and fish is also used in transgenic technology. The question of ＂why make transgenic animals？＂ is very important. Some of the answers to this question are： （1） to obtain new knowledge; （2） to solve the genetic code; （3） to create genetic disease models; （4） to study the genetic control of physiological systems; （5） to improve animal production traits; （6） to produce new animal products. Transgenic technology is one of the main and important tools in the finding solutions to problems of growing population with their applications to different organisms, and takes more attention and interest every day. Transgenic technology creates opportunities and areas to play with organisms to fulfill the demands of people. Because of this, this paper based on mainly transgenic applications to take people＇s attention and exhibit its importance.
