JGM, CRISPR-Cas Systems, Chromatin, Chromosomes, Clustered Regularly Interspaced Short Palindromic Repeats, Genomics, RNA, Guide
Nat Commun 2022 Apr 6; 13(1):1871
HG009900, CCF-1955712, CA034196
Three-dimensional (3D) structures of the genome are dynamic, heterogeneous and functionally important. Live cell imaging has become the leading method for chromatin dynamics tracking. However, existing CRISPR- and TALE-based genomic labeling techniques have been hampered by laborious protocols and are ineffective in labeling non-repetitive sequences. Here, we report a versatile CRISPR/Casilio-based imaging method that allows for a nonrepetitive genomic locus to be labeled using one guide RNA. We construct Casilio dual-color probes to visualize the dynamic interactions of DNA elements in single live cells in the presence or absence of the cohesin subunit RAD21. Using a three-color palette, we track the dynamic 3D locations of multiple reference points along a chromatin loop. Casilio imaging reveals intercellular heterogeneity and interallelic asynchrony in chromatin interaction dynamics, underscoring the importance of studying genome structures in 4D.
Clow, Patricia A; Du, Menghan; Jillette, Nathaniel L.; Taghbalout, Aziz; Zhu, Jacqueline J; and Cheng, Albert, "CRISPR-mediated multiplexed live cell imaging of nonrepetitive genomic loci with one guide RNA per locus." (2022). Faculty Research 2022. 72.