DNA capture by a CRISPR-Cas9–guided adenine base editor

doi:10.1126/science.abb1390

GSTDTAP > 气候变化

DOI	10.1126/science.abb1390
	DNA capture by a CRISPR-Cas9–guided adenine base editor
	Audrone Lapinaite; Gavin J. Knott; Cody M. Palumbo; Enrique Lin-Shiao; Michelle F. Richter; Kevin T. Zhao; Peter A. Beal; David R. Liu; Jennifer A. Doudna
	2020-07-31
发表期刊	Science
出版年	2020
英文摘要	CRISPR-Cas9 base editors comprise RNA-guided Cas proteins fused to an enzyme that can deaminate a DNA nucleoside. No natural enzyme deaminates adenine in DNA, and so a breakthrough came when a natural transfer RNA deaminase was fused to Cas9 and evolved to give an adenine base editor (ABE) that works on DNA. Further evolution provided the enzyme ABE8e, which catalyzes deamination more than 1000 times faster than early ABEs. Lapinaite et al. now present a 3.2-angstrom resolution structure of ABE8e bound to DNA in which the target adenine is replaced with an analog designed to trap the catalytic conformation. The structure, together with kinetic data comparing ABE8e to earlier ABEs, explains how ABE8e edits DNA bases and could inform future base-editor design. Science , this issue p. [566][1] CRISPR-Cas–guided base editors convert A•T to G•C, or C•G to T•A, in cellular DNA for precision genome editing. To understand the molecular basis for DNA adenosine deamination by adenine base editors (ABEs), we determined a 3.2-angstrom resolution cryo–electron microscopy structure of ABE8e in a substrate-bound state in which the deaminase domain engages DNA exposed within the CRISPR-Cas9 R-loop complex. Kinetic and structural data suggest that ABE8e catalyzes DNA deamination up to ~1100-fold faster than earlier ABEs because of mutations that stabilize DNA substrates in a constrained, transfer RNA–like conformation. Furthermore, ABE8e’s accelerated DNA deamination suggests a previously unobserved transient DNA melting that may occur during double-stranded DNA surveillance by CRISPR-Cas9. These results explain ABE8e-mediated base-editing outcomes and inform the future design of base editors. [1]: /lookup/doi/10.1126/science.abb1390
领域	气候变化 ; 资源环境
URL	查看原文
引用统计
文献类型	期刊论文
条目标识符	http://119.78.100.173/C666/handle/2XK7JSWQ/286872
专题	气候变化资源环境科学
推荐引用方式 GB/T 7714	Audrone Lapinaite,Gavin J. Knott,Cody M. Palumbo,等. DNA capture by a CRISPR-Cas9–guided adenine base editor[J]. Science,2020.
APA	Audrone Lapinaite.,Gavin J. Knott.,Cody M. Palumbo.,Enrique Lin-Shiao.,Michelle F. Richter.,...&Jennifer A. Doudna.(2020).DNA capture by a CRISPR-Cas9–guided adenine base editor.Science.
MLA	Audrone Lapinaite,et al."DNA capture by a CRISPR-Cas9–guided adenine base editor".Science (2020).