Background-suppressed live visualization of genomic loci with an improved CRISPR system based on a split fluorophore.

The higher-order structural organization and dynamics of the chromosomes play a central role in gene regulation. To explore this structure-function relationship, it is necessary to directly visualize genomic elements in living cells. Genome imaging based on the CRISPR system is a powerful approach but has limited applicability due to background signals and nonspecific aggregation of fluorophores within nuclei.