Unveiling the pathway to Z-DNA in the protein-induced B–Z transition. Issue 8 (23rd March 2018)

• Record Type: Journal Article
• Authors: Kim, Sook Ho; Lim, So-Hee; Lee, Ae-Ree; Kwon, Do Hoon; Song, Hyun Kyu; Lee, Joon-Hwa; Cho, Minhaeng; Johner, Albert; Lee, Nam-Kyung; Hong, Seok-Cheol
• Is Part Of: Nucleic acids research. Volume 46:Issue 8(2018)
• Page Start: 4129
• Page End: 4137
• Publication Date: 2018-03-23
• Subjects: Nucleic acids -- Periodicals; Molecular biology -- Periodicals; 572.805
• DOI: 10.1093/nar/gky200
• Languages: English
• ISSNs: 0305-1048

Abstract

Abstract: Left-handed Z-DNA is an extraordinary conformation of DNA, which can form by special sequences under specific biological, chemical or physical conditions. Human ADAR1, prototypic Z-DNA binding protein (ZBP), binds to Z-DNA with high affinity. Utilizing single-molecule FRET assays for Z-DNA forming sequences embedded in a long inactive DNA, we measure thermodynamic populations of ADAR1-bound DNA conformations in both GC and TG repeat sequences. Based on a statistical physics model, we determined quantitatively the affinities of ADAR1 to both Z-form and B-form of these sequences. We also reported what pathways it takes to induce the B–Z transition in those sequences. Due to the high junction energy, an intermediate B* state has to accumulate prior to the B–Z transition. Our study showing the stable B* state supports the active picture for the protein-induced B–Z transition that occurs under a physiological setting.