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翅膀螺旋域融合内核酶的特征是依赖N6-甲基氨酸的IV型限制系统

Igor Helbrecht^1,2,3, Daniel Heiter¹, Weiwei Yang¹

¹New England Biolabs, Inc., Ipswich, MA, United States.

Frontiers in microbiology

|April 24, 2024

概括

Prokaryotic 翅膀螺旋 (wH) 域是广泛存在的腺因甲基化传感器. 这项研究确定了利用wH域来读取N6-甲基亚丁 (6mA) DNA修饰的新型融合内核酶.

科学领域:

分子生物学分子生物学
遗传学是一个遗传学.
生物化学生化学

背景情况:

翅膀螺旋 (wH) 域,也称为翅膀螺旋转 (wHTH) 域,对于所有生命形式的DNA结合和感应修改至关重要.
虽然真核 wH 域感知非甲基化 CpG,但 prokaryotic wH 域如 DpnI 和 HhiV4I 检测腺甲基化 (N6-甲基亚丁, 6mA).

研究的目的:

为了研究 prokaryotic wH 域的流行和功能,作为腺因甲基化传感器.
描述新的含有wH域的融合内核酶及其与甲基化DNA的相互作用.

主要方法:

生物信息分析以识别含有wH域的融合内核酶.
识别的内核酶代表的蛋白质净化.
试验室酶分析以评估DNA裂变特异性和甲基化偏好.

主要成果:

确定了新的 prokaryotic 核融合内核酶 (PD-(D/E) XK-wH,PUA-wH-HNH,wH-GIY-YIG,PLD-wH) 在 Dam+ Gm6ATC 环境中感知腺因甲基化.
在试验室中证明了对纯化的wH域内核酶融合的腺甲基化偏好 (不包括PLD-wH家族).
观察到大多数新的融合内核酶,类似于修饰依赖的限制内核酶 (MDREs),在识别序列之外分裂DNA.

结论:

Prokaryotic wH 域广泛应用于各种融合内核酶架构,以读取腺甲基化 (6mA).
这扩大了已知的6mA传感器的范围,并突出了DNA修饰识别中的组合策略.

关键词:

在GIY-YIG内核酶.在HNH内核酶中,HNH内核酶是最重要的.这是一个N6mA依赖的限制系统.在PLD家族的内核酶中.基因组冲突基因组冲突有翅膀的螺旋体融合内核酶 (endonucleases).

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