LSM4, also called U6 snRNA-associated Sm-like protein or glycine-rich protein (GRP), forms donutshaped heptameric complexes that are involved in various steps of RNA metabolism. It facilitates RNA protein interactions and structural changes that are required during ribosomal subunit assembly. It binds specifically to the 3'-terminal U-tract of U6 snRNA. Recombinant human LSM4 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography.