Graduate School of Arts and Sciences, The University of Tokyo , Komaba, Meguro-ku, Tokyo 153-8902, Japan.
ACS Chem Biol. 2014 Mar 21;9(3):617-21. doi: 10.1021/cb400836k. Epub 2014 Jan 17.
Vivid (VVD) is a photoreceptor derived from Neurospora Crassa that rapidly forms a homodimer in response to blue light. Although VVD has several advantages over other photoreceptors as photoinducible homodimerization system, VVD has a critical limitation in its low dimer-forming efficiency. To overcome this limitation of wild-type VVD, here we conduct site-directed saturation mutagenesis in the homodimer interface of VVD. We have found that the Ile52Cys mutation of VVD (VVD-52C) substantially improves its homodimer-forming efficiency up to 180%. We have demonstrated the utility of VVD-52C for making a light-inducible gene expression system more robust. In addition, using VVD-52C, we have developed photoactivatable caspase-9, which enables optical control of apoptosis of mammalian cells. The present genetically engineered photoinducible homodimerization system can provide a powerful tool to optically control a broad range of molecular processes in the cell.
Vivid（VVD）是一种源自粗糙脉孢菌的光感受器，它能快速形成同源二聚体以响应蓝光。尽管 VVD 在作为光诱导同源二聚化系统方面具有优于其他光感受器的几个优点，但它在同源二聚化效率方面存在一个关键的局限性。为了克服野生型 VVD 的这一局限性，我们在 VVD 的同源二聚体界面进行了定点饱和突变。我们发现 VVD 的 Ile52Cys 突变（VVD-52C）将其同源二聚化效率显著提高至 180%。我们已经证明了 VVD-52C 在构建更稳健的光诱导基因表达系统方面的实用性。此外，我们使用 VVD-52C 开发了光激活型 Caspase-9，它能够实现对哺乳动物细胞凋亡的光控。本研究中的基因工程光诱导同源二聚化系统可为光学控制细胞内广泛的分子过程提供有力工具。
