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lifflefield 发表于 2011-9-26 13:22
我所说的,应该是我表示学术上最大的通俗性,所以势必有学术上的误差,因为这不是学术文章。改造过的rAAV ...
AAV genome, transcriptome and proteomeThe AAV genome is built of single-stranded deoxyribonucleic acid (ssDNA), either positive- or negative-sensed, which is about 4.7 kilobase long. The genome comprises inverted terminal repeats (ITRs) at both ends of the DNA strand, and two open reading frames (ORFs): rep and cap. The former is composed of four overlapping genes encoding Rep proteins required for the AAV life cycle, and the latter contains overlapping nucleotide sequences of capsid proteins: VP1, VP2 and VP3, which interact together to form a capsid of an icosahedral symmetry.[11]
[edit] ITR sequencesThe Inverted Terminal Repeat (ITR) sequences comprise 145 bases each. They were named so because of their symmetry, which was shown to be required for efficient multiplication of the AAV genome.[12] Another property of these sequences is their ability to form a hairpin, which contributes to so-called self-priming that allows primase-independent synthesis of the second DNA strand. The ITRs were also shown to be required for both integration of the AAV DNA into the host cell genome (19th chromosome in humans) and rescue from it,[13][14] as well as for efficient encapsidation of the AAV DNA combined with generation of a fully assembled, deoxyribonuclease-resistant AAV particles.[15]
With regard to gene therapy, ITRs seem to be the only sequences required in cis next to the therapeutic gene: structural (cap) and packaging (rep) genes can be delivered in trans. With this assumption many methods were established for efficient production of recombinant AAV (rAAV) vectors containing a reporter or therapeutic gene. However, it was also published that the ITRs are not the only elements required in cis for the effective replication and encapsidation. A few research groups have identified a sequence designated cis-acting Rep-dependent element (CARE) inside the coding sequence of the rep gene. CARE was shown to augment the replication and encapsidation when present in cis.[16][17][18][19]
"释放k因子,只有一次侵染。这个基因改造病毒,是在体外培养好的,并不需要人体培养,当培养好的改造过的rAAV病毒,进入肝脏,只做一次侵染,同时我们构建四环素调控抗生素,只有注射四环素,rAAV病毒才开始生成k因子,一旦病人体内乙肝病毒被清除干净后,停止服用四环素,rAAV病毒就会停止生产K因子。"
"只有一次侵染" - 这可能吗?
"释放k因子" - 这可能吗?
"四环素调控抗生素" (Regulation of Gene Expression by Tetracycline) -也很难.
"你所查到的是天然rAAV病毒。" - rAAV recombinant AAV is a type of recombinant DNA:
重組DNA是一种人工合成的脱氧核糖核酸。它是把一般不同时出现的DNA序列组合到一起而产生的[1]。从遺傳工程的观点来看重組DNA是把相关的DNA添加到已有生物的基因組中,比如细菌的质粒中,其目的是为了改变或者添加特别是的特性,比如免疫[1]。重組DNA与遺傳重組不是一回事。它不是重组细胞内或者染色体上已经存在的基因组,而完全是通过外部工程达到的[1]。重组蛋白质是从重組DNA合成出来的蛋白质[2]。
重組DNA技术是1973年由斯坦利·诺曼·科恩和赫伯特·玻意尔设计的。1974年他们发表了他们的设计[3]。在这篇论文中他们描述了分离和放大基因或者DNA片断,然后精确地把它们插入其它细胞中,由此制造出转基因细菌。沃納·亞伯、丹尼爾·那森斯和漢彌爾頓·史密斯发明了限制酶才使得重組DNA技术可行,为此他们获得了1978年诺贝尔医学奖。
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