果蝇转座因子对基因组进化的影响

真核生物基因组织有很多可移动ＤＮＡ片段为称转座因子,果蝇是大量系统研究的最好实验材料之一,其基因组的１０％－１２％是由转座因子组成,在宿主中,ＴＥs也许改变基因表达模型,也许改变ＯＲＦs编码序列,也许对细胞功能产生影响,这此因子遗传的可动性也可能使它们适于建造载体产生转基因生物。因此,对ＴＥs进化的动态研究以及对宿主基因组进化影响的探索将有助于TEs作为载体的细胞工程研究。     

果蝇P转座因子的研究进展

果蝇P因子是DNA转座子,在近几十年里受到很大关注。可用于确认有关基因,克隆基因以及安置基因回到基因组。P因子的高易动性及其保持和对内部序列强烈的修饰作用也是P因子的本质特征。P因子的另一重要用途是用于产生转基因果蝇。目的基因置于质粒内P因子中可在转座酶的作用下插入前胚盘胚。携带目的基因的P因子可从质粒转座到任意染色体上。据报道,在典型实验中,插入可育果蝇的10％～20％可产生转化体后裔。但是以这种可动DNA片段作为载体尚存在转移基因的不稳定性及与内源跳跃基因的相互影响。本文介绍了果蝇P转座因子的一些研究进展。这些因子的遗传可动性也使它们适用于建造载体产生转基因生物。若如此,载体导入外源基因组的遗传稳定性问题将是一个重要课题。 Abstract：P elements in D.melanogaster are DNA transposons and received greater attention within the last few decades.P elements are used for identifying genes of interest,for cloning them,and for placing them back into the genome.The high mobility of P elements and their retention of this mobility and drastic modiffications to their internal sequences are also essential features.Another most important use of P elements is that of making transgenic flies.Desired gene is placed between P-element ends,usually within a plasmid,and injected into preblastoderm embryos in the presence of transposase.This P element then transposes from the plasmid to a random chromosomal site.Reported in a typical experiment,10％～20％ of the fertile injected flies produce transformant progeny.But the instability of the transferred gene carried on a piece of mobile DNA as a vector and its interaction with endogenous jumping genes.This paper introduced the studies advances of P transposable element in Drosophila.The genetic mobility of these elements can also make them suitable for the construction of vectors to create transgenic organisms.If so,the genetic stability of the vectors introduced to a foreign genome should be a important subject.