Tang Mei, Cecconi Ciro, Kim Helen, Bustamante Carlos, Rio Donald C
Division of Genetics, Genomics and Development, Department of Molecular and Cell Biology, Center for Integrative Genomics, University of California, Berkeley, California 94720, USA.
Genes Dev. 2005 Jun 15;19(12):1422-5. doi: 10.1101/gad.1317605.
P transposable elements in Drosophila are members of a larger class of mobile elements that move using a cut-and-paste mechanism. P-element transposase uses guanosine triphosphate (GTP) as a cofactor for transposition. Here, we use atomic force microscopy (AFM) to visualize protein-DNA complexes formed during the initial stages of P-element transposition. These studies reveal that GTP acts to promote assembly of the first detectable noncovalent precleavage synaptic complex. This initial complex then randomly and independently cleaves each P-element end. These data show that GTP acts to promote protein-DNA assembly, and may explain why P-element excision often leads to unidirectional deletions.
果蝇中的P转座因子是一类更大的移动因子的成员，它们通过剪切粘贴机制进行移动。P因子转座酶使用鸟苷三磷酸（GTP）作为转座的辅助因子。在这里，我们使用原子力显微镜（AFM）来观察P因子转座初始阶段形成的蛋白质-DNA复合物。这些研究表明，GTP起到促进第一个可检测到的非共价切割前突触复合物组装的作用。这个初始复合物随后随机且独立地切割每个P因子末端。这些数据表明，GTP起到促进蛋白质-DNA组装的作用，并且可能解释了为什么P因子切除常常导致单向缺失。
