Scientists working in the Marine Biology Laboratory at the University of Chicago have announced a breakthrough. The team has achieved the first gene knockout NSF pod using the squid Doryteuthis pealeii. That particular squid is described as an “exceptionally important” research organism for biology over the last 100 years.
For their achievement, the team used CRISPR-Cas9 genome editing to knock out a pigmentation gene in squid embryos. Removing that gene eliminated pigmentation in the eye and skin cells with high-efficiency. The image above shows a regular squid with black eyes and dots and the pinkish eyes and no dot squid that was modified.
Researchers say that the feat is a critical first step toward the ability to knock out and knock in genes in cephalopods to address a host of biological questions. Cephalopods are important to researchers because they have the largest brain of all invertebrates and a distributed nervous system that allows for instant camouflage and sophisticated behaviors. Studies of the squid could open avenues for applications in a wide range of fields, from medicine to robots and material science.
Being able to remove specific genes as a step towards having the capacity to knock in genes to facilitate research. Genes for things like fluorescent proteins that can be imaged to track neural activity or other dynamic processes could eventually be added. One major challenge of the operation was delivering the CRISPR-Cas system into the single-cell squid embryo.
The technique involved developing micro-scissors to clip the very tough outer surface of the egg and a beveled quartz needle to deliver CRISPR-Cas9 reagents through the cut. Studying this particular type of squid has led to foundational advances in neurobiology. In the 1950s, Alan Hodgkin and Andrew Huxley became Nobel Prize laureates for their work on action potential with the species.