CASC3
Description
The CASC3 (CASC3 exon junction complex subunit) is a protein-coding gene located on chromosome 17.
CASC3 is a protein encoded by the CASC3 gene in humans. It is a core component of the exon junction complex (EJC), which is deposited on spliced mRNAs at exon-exon junctions and functions in nonsense-mediated mRNA decay (NMD). CASC3 binds RNA and interacts with other EJC core components. It is primarily located in the cytoplasm but shuttles into the nucleus where it localizes to nuclear speckles.
CASC3 is essential for pre-mRNA splicing as a component of the spliceosome. It is a core component of the exon junction complex (EJC), which is deposited at splice junctions on mRNAs. The EJC is a dynamic structure composed of core proteins and peripheral factors that transiently associate during EJC assembly or subsequent mRNA metabolism. The EJC marks exon-exon junctions in mature mRNA, guiding gene expression machinery. Core components remain bound to spliced mRNAs throughout mRNA metabolism, influencing processes like nuclear mRNA export, subcellular mRNA localization, translation efficiency, and nonsense-mediated mRNA decay (NMD). CASC3 enhances the ATPase and RNA-helicase activities of EIF4A3. It plays a role in the stress response by participating in cytoplasmic stress granule assembly and promoting cell recovery after stress. CASC3 is a component of dendritic ribonucleoprotein particles (RNPs) in hippocampal neurons, potentially contributing to mRNA transport. It binds spliced mRNA in a sequence-independent manner, 20-24 nucleotides upstream of exon-exon junctions. It binds poly(G) and poly(U) RNA homomers.
CASC3 is also known as BTZ, MLN51.
