DLG4

DLG4, also known as Discs large homolog 4, and by other names such as Postsynaptic density protein 95 (PSD-95), Synapse-associated protein 90 (SAP-90), or SAP90, is a protein highly expressed in the brain, encoded by a gene in human cells. The mechanism of action for DLG4 primarily involves serving as a component of the postsynaptic density (PSD), where it interacts with multiple proteins through its PDZ domains, SH3 domain, and guanylate kinase-like domain (GKLD). DLG4 is involved in regulating synaptic maturation, morphology, and function by interacting with proteins such as NMDA receptor subunits and potassium channels.

DLG4 plays a key role in synapse formation and synaptic plasticity, impacting learning and memory processes. Abnormal expression or dysfunction of DLG4 is associated with various neurological disorders, including intellectual disability, autism, attention deficit hyperactivity disorder (ADHD), and epilepsy. Mutations or abnormal splicing of DLG4 can lead to neurodevelopmental disorders, such as DLG4-related synaptic pathology, manifesting as early-onset global developmental delay, intellectual disability, autism spectrum disorder, and ADHD.