日本东京大学Moritoshi Sato研究组开发出用于深层组织光遗传学操控的红光响应性开关。该项研究成果于2022年6月13日在线发表在《自然—生物技术》杂志上。

研究人员提出了MagRed，一种红光可激活的光开关，它由一个吸收红光的细菌植物色素组成，其中包含一个哺乳动物的内源性发色团，胆绿素和一个光态特异性结合因子（通过Affibody库选择开发）。红光照明触发了MagRed的两个组成部分的结合，以及与它们融合的分裂蛋白的组装。通过利用MagRed，研究人员开发了一种红光可激活的Cre重组酶，它能在哺乳动物组织深处进行光激活的DNA重组。

研究人员还创建了基于CRISPR-Cas9的红光诱导转录调节器，使多个内源性目标基因的激活率高达378倍（平均135倍的诱导率）。MagRed将促进光遗传学在各种生物研究领域深入哺乳动物体内的应用。

据介绍，红光能深入到哺乳动物组织中，而且光毒性低，但使用红光的光遗传学工具却很少被开发。

附：英文原文

Title: A red light–responsive photoswitch for deep tissue optogenetics

Author: Kuwasaki, Yuto, Suzuki, Kazushi, Yu, Gaigai, Yamamoto, Shota, Otabe, Takahiro, Kakihara, Yuki, Nishiwaki, Michiru, Miyake, Keita, Fushimi, Keiji, Bekdash, Ramsey, Shimizu, Yoshihiro, Narikawa, Rei, Nakajima, Takahiro, Yazawa, Masayuki, Sato, Moritoshi

Issue&Volume: 2022-06-13

Abstract: Red light penetrates deep into mammalian tissues and has low phototoxicity, but few optogenetic tools that use red light have been developed. Here we present MagRed, a red light–activatable photoswitch that consists of a red light–absorbing bacterial phytochrome incorporating a mammalian endogenous chromophore, biliverdin and a photo-state-specific binder that we developed using Affibody library selection. Red light illumination triggers the binding of the two components of MagRed and the assembly of split-proteins fused to them. Using MagRed, we developed a red light–activatable Cre recombinase, which enables light-activatable DNA recombination deep in mammalian tissues. We also created red light–inducible transcriptional regulators based on CRISPR–Cas9 that enable an up to 378-fold activation (average, 135-fold induction) of multiple endogenous target genes. MagRed will facilitate optogenetic applications deep in mammalian organisms in a variety of biological research areas.

DOI: 10.1038/s41587-022-01351-w

Source: https://www.nature.com/articles/s41587-022-01351-w