# Illuminating the genome: emerging approaches in CRISPR-Cas live-cell imaging

## TL;DR

CRISPR-Cas live-cell imaging is a powerful tool for studying genome dynamics in real time, with recent advances improving its effectiveness for non-repetitive genomic regions.

## Contribution

The paper reviews recent innovations in CRISPR imaging that enhance labeling of non-repetitive loci and address key technical limitations.

## Key findings

- Multicolor labeling and amplification systems improve signal-to-background ratios in CRISPR imaging.
- Novel fluorescent reporters enable visualization of non-repetitive genomic loci.
- Prolonged CRISPR expression still causes cellular toxicity and genomic instability.

## Abstract

CRISPR-Cas-based live-cell imaging has rapidly become a central technology for studying genome dynamics with high specificity and flexibility. By coupling nuclease-deactivated Cas (dCas) with programmable guide RNAs, genomic loci can be tracked in living cells, providing direct insights into nuclear organization and chromatin behavior. While repetitive regions such as telomeres and centromeres are readily visualized, labeling non-repetitive loci remains more challenging due to weak signals and high background. Recent advances, including multicolor labeling strategies, innovative amplification systems based on dCas9 and single-guide RNA (sgRNA) engineering, and integration with novel fluorescent reporters, have markedly expanded the applicability of CRISPR imaging across the genome. These developments have expanded the multiplexing capacity of CRISPR imaging, improved signal-to-background ratios, and even enabled the visualization of non-repetitive genomic loci. Nonetheless, key challenges remain, including cellular toxicity, replication stress, and genomic instability associated with prolonged CRISPR expression. In this review, we summarize recent advances in CRISPR live-cell imaging and highlight key design trade-offs and biological constraints.

Graphical Abstract