SRPK3 (serine/arginine-rich protein kinase 3) is an X-linked serine/threonine kinase that phosphorylates SR-domain-containing proteins, particularly SRSF1, and plays critical roles in neurodevelopment and muscle biology. The kinase localizes to both cytoplasm and nucleus where it regulates mRNA processing and spliceosomal assembly 1. Primary function: SRPK3 is essential for normal cognitive and ocular development 1. It also contributes to skeletal muscle development, with expression highest during fetal muscle development 2. The protein interacts at post-transcriptional levels with other muscle proteins 3. Mechanism: SRPK3 regulates dopaminergic neuron survival and α-synuclein expression levels 4. Pathogenic variants disrupt normal neuromuscular development and cellular function. Disease relevance: Loss-of-function SRPK3 variants cause X-linked intellectual disability (XLID) characterized by intellectual disability, corpus callosum agenesis, abnormal eye movements, and ataxia 15. Additionally, digenic inheritance of SRPK3 and TTN variants causes early-onset skeletal muscle myopathy with myofibrillar disorganization 36. SRPK3 dysfunction is implicated in breast cancer pathogenesis 7. Clinical significance: SRPK3 emerges as a novel therapeutic target; selective SRPK3 inhibitors show promise for cancer treatment 7. Understanding SRPK3's role in neurodevelopmental and neuromuscular disorders provides new avenues for diagnosis and intervention in affected patients.