Illustration based on the X-ray structure of the human NOVA2 RNA-binding domain (grey) in complex with a synthetic RNA (ribonucleic acid) oligonucleotide (red). NOVA (neuro-oncological ventral antigen) proteins play an important role in neuronal (nerve cell) development and in the adult brain. By binding to mRNA (messenger RNA) they regulate a process, alternative splicing, that generates protein variants with different functions from a single gene. These variants are needed at different times and locations during development. Mutations in NOVA2 lead to neurodevelopmental and intellectual disabilities.