UNC79 is an auxiliary subunit of the NALCN sodium leak channel complex that is essential for regulating neuronal excitability and resting membrane potential 1. Structurally, UNC79 is a massive HEAT-repeat protein that forms an intertwined anti-parallel superhelical assembly with UNC80, creating a cytoplasmic scaffold that docks onto the NALCN-FAM155A pore-forming subcomplex 12. This UNC79-UNC80 assembly specifically associates with NALCN through the intracellular II-III linker, and disruption of these interactions significantly reduces NALCN-mediated currents 2. The complex mediates background sodium leak currents that depolarize neurons and is regulated by extracellular calcium through G protein-dependent mechanisms 3. UNC79 is critical for fundamental neurological processes including respiratory rhythm, circadian rhythm, and locomotion 4. Recent clinical evidence demonstrates that heterozygous loss-of-function variants in UNC79 cause a neurodevelopmental disorder characterized by intellectual disability, developmental delay, epilepsy, and behavioral issues in six unrelated patients 5. Animal models confirm UNC79's essential role, with knockout mice showing learning and memory impairments and developmental delays 5. The evolutionary conservation of UNC79 across eukaryotes underscores its fundamental importance in cellular excitability 6.