Factors affecting transposition of the Himar1 mariner transposon in vitro.
Factors affecting transposition of the Himar1 mariner transposon in vitro.
复制标题
DOI：
--
复制
发表时间：
1998-05
期刊：
影响因子：
3.3
通讯作者：
D. Lampe;Theresa E. Grant;H. Robertson
中科院分区：
文献类型：
--
作者：
D. Lampe;Theresa E. Grant;H. Robertson
Mariner家族转座因子在动物中广泛存在，但人们对它们的调控知之甚少，部分原因是已知只有两种转座因子具有功能。这些是来自毛里求斯果蝇 (Drosophila mauritiana) 的 Dmmar1 元件的特定拷贝，例如 Mos1，以及来自角蝇 (Haematobia irritans) 的 Himar1 元件的共有序列。对体外转座系统进行了改进，以研究影响 Himar1 转座的几个参数。转座产物在 6 小时内线性累积。转座频率随着温度的升高而增加，并且取决于 Mg2+ 浓度。转座频率在转座酶浓度的狭窄范围内达到峰值。 Mos1 在体内观察到的现象是在较高浓度下的下降，这支持了水手可能部分受到“过度生产抑制”调节的建议。随着转座子大小的增加，转座频率呈指数下降，并受到供体位点侧翼 DNA 序列的影响。目标位点使用中的明显偏差表明倾向于插入弯曲或可弯曲的 DNA 序列，而不是 TA 目标位点之外的任何特定核苷酸序列。
Mariner family transposable elements are widespread in animals, but their regulation is poorly understood, partly because only two are known to be functional. These are particular copies of the Dmmar1 element from Drosophila mauritiana, for example, Mos1, and the consensus sequence of the Himar1 element from the horn fly, Haematobia irritans. An in vitro transposition system was refined to investigate several parameters that influence the transposition of Himar1. Transposition products accumulated linearly over a period of 6 hr. Transposition frequency increased with temperature and was dependent on Mg2+ concentration. Transposition frequency peaked over a narrow range of transposase concentration. The decline at higher concentrations, a phenomenon observed in vivo with Mos1, supports the suggestion that mariners may be regulated in part by "overproduction inhibition." Transposition frequency decreased exponentially with increasing transposon size and was affected by the sequence of the flanking DNA of the donor site. A noticeable bias in target site usage suggests a preference for insertion into bent or bendable DNA sequences rather than any specific nucleotide sequences beyond the TA target site.