CDKL5 Gene: Function, Mutations, and Associated Disorders | NCBI, UniProt, OMIM

The CDKL5 gene encodes a serine/threonine-protein kinase that belongs to the cyclin-dependent kinase (CDK) family. It is predominantly expressed in the brain, where it plays critical roles in neuronal maturation, dendritic arborization, axonal outgrowth, and synaptic plasticity. CDKL5 phosphorylates multiple substrates including MeCP2, DNMT1, and MAP1S, thereby regulating gene expression, DNA methylation, and cytoskeletal dynamics. Loss-of-function mutations in CDKL5 cause CDKL5 deficiency disorder (CDD), a severe X-linked dominant neurodevelopmental condition characterized by early-onset epilepsy, intellectual disability, and Rett-like features.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• CDKL5 signaling in neuronal development (Reactome: R-HSA-9006934)

• MeCP2 and CDKL5 pathway (KEGG: hsa05034)

• Synaptic plasticity and dendritic spine regulation (WikiPathways: WP3932)

CDKL5 (cyclin-dependent kinase-like 5) is a 1030-amino-acid serine/threonine-protein kinase with an N-terminal catalytic domain and a long C-terminal regulatory region. It localizes to both the nucleus and cytoplasm, where it phosphorylates key substrates such as MeCP2, DNMT1, and MAP1S. CDKL5 activity is essential for neuronal maturation, dendritic spine formation, and synaptic transmission. Mutations that disrupt its kinase function or subcellular localization lead to CDKL5 deficiency disorder, a severe early-onset epileptic encephalopathy. The protein is highly expressed in brain regions including cortex, hippocampus, and cerebellum.