Kalirin (RhoGEF kinase) (KALRN)

Kalirin is a multidomain scaffold protein encoded by the KALRN gene, primarily known for its function as a guanine nucleotide exchange factor (GEF) that activates Rho-family small GTPases, such as Rac1, RhoG, and RhoA[1][2][3][5]. It contains multiple functional domains, including Dbl homology (DH) and pleckstrin homology (PH) regions, and can also exhibit serine/threonine kinase activity. Kalirin has numerous isoforms resulting from alternative splicing, with Kalirin-7, -9, and -12 being most prevalent in the brain. It plays a critical role in neurite outgrowth, dendritic spine formation, and synaptic plasticity, and is involved in the development and function of neuronal circuits. The biological significance of Kalirin is underscored by its association with diseases involving synaptic dysfunction or cognitive impairment, including schizophrenia and autism spectrum disorder. Loss-of-function or variant mutations in KALRN have been shown to impair synaptic connectivity and function[1][2][3][4][5]. Kalirin also interacts with numerous synaptic proteins, such as NMDA receptor subunits and DISC1, regulating synaptic strength and plasticity. Although not yet the direct target of approved drugs, its central role in nervous system pathology makes it a potential therapeutic target in neuropsychiatric and neurodegenerative diseases[1][2][3][5].

Other names

DUETDUOHAPIPTRADHuntingtin-associated protein-interacting proteinProtein DuoSerine/threonine-protein kinase with Dbl- and pleckstrin homology domainARHGEF24KALNC2

Modulation of RhoGTPase activity (predominantly Rac1, also RhoG and RhoA) via exchange of GDP for GTP Promotion or inhibition of synaptic plasticity Alteration of dendritic spine morphology and number