Signal Management

To lay a new network of roads, you need someone to interpret the plan and direct the construction. In the developing brain, as the dense network of connections forms, this navigator role is in part played by Cas adaptor proteins. A new study has found that without them to relay external signals to the growing internal cell skeleton, major wiring pathways in the developing mouse brain go awry. The team showed that Cas proteins (green) are present within growing brain cell protrusions called axons (red in the developing brain section pictured). In neurons, they help ensure axons bundle together properly, holding hands as they cross the brain. In support cells, they help prepare the landing zone so projecting axons hit the target as they reach between thalamus and cortex brain regions. Understanding these guidance systems helps explain how developmental brain disorders can arise when wiring goes wrong.

Written by Anthony Lewis

Anthony Lewis

Writer

Ant was the web editor in the early days of BPoD, and has since worked with the UK’s top science organisations as a writer and multimedia producer. He now splits his time between freelance work and managing multimedia at The Lancet.

Website

• Image from work by Jason A. Estep and Alyssa M. Treptow, and colleagues
• Cell, Molecular and Developmental Biology Graduate Program, Department of Molecular, Cell & Systems Biology, University of California, Riverside, CA, USA
• Image originally published with a Creative Commons Attribution 4.0 International (CC BY 4.0)
• Published in PLOS Genetics, November 2025