RecA核蛋白丝的一种新特性：双链DNA的反式链交换激活。
A novel property of the RecA nucleoprotein filament: activation of double- stranded DNA for strand exchange in trans.
作者信息
Mazin A V, Kowalczykowski S C
机构信息
Division of Biological Sciences, Sections of Microbiology and of Molecular and Cellular Biology, University of California, Davis, California 95616-8665, USA.
出版信息
Genes Dev. 1999 Aug 1;13(15):2005-16. doi: 10.1101/gad.13.15.2005.
RecA protein catalyzes DNA strand exchange, a basic step of homologous recombination. Upon binding to single-stranded DNA (ssDNA), RecA protein forms a helical nucleoprotein filament. Normally, this nucleoprotein filament binds double-stranded DNA (dsDNA) and promotes exchange of base pairs between this dsDNA and the homologous ssDNA that is contained within this filament. Here, we demonstrate that this bound dsDNA can be activated by interaction with a heterologous RecA nucleoprotein filament for a novel type of strand exchange with homologous ssDNA that is external to, and, therefore, not within, the filament. We refer to this novel DNA strand exchange as being in trans. Thus, the RecA nucleoprotein filament is a protein scaffold that activates dsDNA for strand exchange with ssDNA either within the filament or external to it. This new property demonstrates that the RecA nucleoprotein filament makes dsDNA receptive for DNA strand exchange, and it defines an early step of the homology recognition mechanism.
RecA蛋白催化DNA链交换，这是同源重组的一个基本步骤。与单链DNA（ssDNA）结合后，RecA蛋白形成螺旋状核蛋白丝。通常情况下，这种核蛋白丝会结合双链DNA（dsDNA），并促进该dsDNA与包含在该丝中的同源ssDNA之间的碱基对交换。在此，我们证明，这种结合的dsDNA可通过与异源RecA核蛋白丝相互作用而被激活，从而与丝状体外的同源ssDNA进行一种新型的链交换。我们将这种新型DNA链交换称为反式链交换。因此，RecA核蛋白丝是一种蛋白质支架，可激活dsDNA与丝状体内或丝状体外的ssDNA进行链交换。这一新特性表明，RecA核蛋白丝使dsDNA易于进行DNA链交换，并定义了同源性识别机制的早期步骤。
Zotero 插件