Genetic code enables zebrafish to mend damaged organs

Zebrafish have the remarkable and rare ability to regrow and repair their hearts after damage. New research from Caltech and UC Berkeley has identified the circuit of genes controlling this ability and offers clues about how a human heart might someday be repaired after damage, such as a heart attack or in cases of congenital heart defects.

In the new study, the team found that the heart cells derived from neural crest cells are responsible for orchestrating the reconstruction process in damaged zebrafish hearts. When those neural crest–derived heart cells were removed in experiments, the hearts lost their ability to regenerate after damage.

Importantly, the study identified the complex circuit of genes that is activated during regeneration. These genes, the researchers found, are crucial for normal embryonic development and then are inactivated during the animal's adult life – but are reactivated to enable tissue regeneration.

Next, the team aims to study how these cells reactivate such gene programs to answer the question: What signal triggers the activation of these genes after damage? Ultimately, the work could reveal whether humans could activate analogous genes if given that same signal.

The Martik team is currently using CRISPR technology – a common gene-editing technique – on human heart cells in lab dishes to determine if these genes can be reactivated.

Image source: M. Martik.