These small GTPases were once characterized as high affinity intracellular receptors for the second messenger diacylglycerol (DAG) and the phorbol ester tumor promoters.
The α and β isoforms are almost identical, the key difference stems from the SH2 domain at the N-terminal.
α1-Chimerin is also able to regulate dendritic spinal density by binding to NMDA receptors at the NR2A subunit.
Beta-chimerin (Rho GTPase-activating protein 3, 468aa) is mainly found in the brain and pancreas and the expression is in the form of reduced malignant gliomas.
Mutations in α2-chimerin can cause disorders such as Duane Retraction Syndrome as it changes the signals on how the eye moves.