Developing mouse models for functional studies of locus-specific DNA methylation

PROJECT SUMMARY The importance of DNA methylation in human health and disease is clear. The fundamental role of DNA methylation in normal development and disease processes, however, remains elusive. The use of gene targeting in animal models definitively demonstrated that genetic mutations at specific genes cause disease. An analogous “epigenetic gene targeting” approach is urgently needed to advance the field of epigenetics and human disease. In this regard, we developed the mouse model with an inducible CRISPR/Cas9 system for targeted manipulation of DNA methylation in vivo. Our preliminary data demonstrated that this system provides unparalleled simplicity in designing DNA methylation modifications or conducing epigenome engineering. Based on these findings, this proposal responds to PAR-21-167: Development of Animal Models and Related Biological Materials for Research. Our overall goals are to develop simple, robust, and reliable tools for targeted editing of locus- specific DNA methylation; these will have broad utility in epigenetic research. Specifically, we will: 1− Utilizing inducible dCas9-SunTagTET1 mice for precise targeted DNA demethylation. 2− Developing inducible dCas9- SunTagDNMT3A-3L mice for targeted DNA methylation. The successful completion of the proposed studies will open entirely new avenues in the field of epigenetics: investigators will be able to 1) test primary functional roles of DNA methylation in vivo, 2) understand how DNA methylation modifications work together to cause biological phenotypes, and 3) design and test targeted therapeutic approaches for epigenetic disorders. The epigenetic gene targeting approaches we propose to develop will be widely utilized and accessible to a range of investigators interested in functional epigenomics and human diseases.