Indian Scientists Develop GlowCas9 for Real-Time CRISPR Tracking

GlowCas9 Breakthrough Enables Real-Time Visualisation of Gene Editing in Living Cells

Scientists at the Bose Institute, Kolkata , have developed GlowCas9 , a glowing version of the CRISPR gene-editing protein that allows researchers to observe genome editing in real time inside living cells . This innovation addresses a long-standing limitation in gene-editing research, where molecular activity could only be studied after cells were fixed or destroyed.

Why Real-Time Monitoring Was a Challenge

CRISPR-Cas9 has transformed genetic research by enabling precise DNA cutting and repair. However, conventional detection methods required terminating cellular activity, making it impossible to track how Cas9 behaves dynamically within living systems. This gap limited understanding of efficiency, timing and precision during gene correction.

Design and Working of GlowCas9

GlowCas9 was engineered by fusing Cas9 with a split nano-luciferase enzyme derived from deep-sea shrimp proteins. When Cas9 folds correctly and becomes active, the luciferase fragments reunite, producing a bioluminescent signal . This light emission serves as a direct indicator of CRISPR activity, enabling continuous, non-destructive monitoring in living cells, tissues and even plant leaves .

Advantages for Gene Therapy

The new system shows enhanced thermal stability , making it suitable for therapeutic environments where enzymes must remain active over time. GlowCas9 also improves homology-directed repair (HDR) —a crucial pathway for correcting inherited genetic disorders such as sickle cell anaemia and muscular dystrophy . To demonstrate its precision, researchers successfully inserted a programmed DNA sequence spelling “ACHARYA” into a genome.

Future Implications

GlowCas9 introduces the concept of “theratracking” , where therapeutic gene editing can be visually tracked as it occurs. Its success in plant systems also opens possibilities for non-transgenic crop improvement , expanding its impact beyond medicine.

Exam Point

• GlowCas9 developed at Bose Institute, Kolkata .

• Uses split nano-luciferase to emit light during Cas9 activation.

• Enhances thermal stability and homology-directed repair .

• Published in Angewandte Chemie International Edition (2025) .