The LSM3 protein plays a crucial role in pre-mRNA splicing as a component of the U4/U6-U5 tri-snRNP complex involved in spliceosome assembly and as part of the precatalytic spliceosome (spliceosome B complex). The heptameric LSM2-8 complex (including LSM3) specifically binds to the 3-end U strand of U6 snRNA. LSM3 Protein, Human (His) is the recombinant human-derived LSM3 protein, expressed by E. coli , with N-His labeled tag.