Generation of Loops in DsDNA
A single molecule study using atomic force microscopy (AFM) and tethered particle motion (TPM) has observed that ISWI can bound naked DNA in absence ATP wrapping DNA around the protein. In presence of ATP, the protein generates DNA loops while simultaneously generating negative supercoils in the template. The first figure in this paper shows three AFM images from where single DNA interacting with ISWI was deposed on mica surfaces. On the center, a single ISWI is bound near the end of a dsDNA template. The right image shows two DNA loops generated by ISWI. These loops contains supercoils. The TPM study instead showed that the duration of loop formed by ISWI was ATP-dependent.
Read more about this topic: Imitation SWI
Famous quotes containing the words generation and/or loops:
“Our Indian said that he was a doctor, and could tell me some medicinal use for every plant I could show him ... proving himself as good as his word. According to his account, he had acquired such knowledge in his youth from a wise old Indian with whom he associated, and he lamented that the present generation of Indians “had lost a great deal.””
—Henry David Thoreau (1817–1862)
“In the labyrinth of a difficult text, we find unmarked forks in the path, detours, blind alleys, loops that deliver us back to our point of entry, and finally the monster who whispers an unintelligible truth in our ears.”
—Mason Cooley (b. 1927)