Recombinant Human Small nuclear ribonucleoprotein Sm D1 (Sm-D1) Fragment (residues 1-87) is a high-purity protein designed for studying spliceosome assembly and pre-mRNA splicing mechanisms. This fragment fully encompasses the functional Sm domain, making it an ideal tool for investigating domain-specific interactions in snRNP complexes.

Small nuclear ribonucleoprotein Sm D1 (SNRPD1) serves as a core component of spliceosomal U1, U2, U4, and U5 small nuclear ribonucleoproteins (snRNPs), which are fundamental building blocks of the spliceosome. It participates in both the pre-catalytic B complex and activated C complex stages of spliceosome assembly and is also involved in the minor spliceosome for U12-type intron splicing. The protein may function as a charged scaffold that promotes snRNP assembly and strengthens snRNP-snRNP interactions through electrostatic contacts with RNA. Cellular localization studies show Sm-D1 is initially assembled in the cytosol before being transported to the nucleus via S