The SMN complex is essential for the assembly of small nuclear ribonucleoproteins (snRNPs), which form the building blocks of the spliceosome and are critical for pre-mRNA splicing. Most spliceosomal snRNPs share a common set of Sm proteins—SNRPB, SNRPD1, SNRPD2, SNRPD3, SNRPE, SNRPF, and SNRPG—that form a heptameric ring on the Sm site of small nuclear RNA, creating the Sm core.
In the cytoplasm, the Sm proteins SNRPD1, SNRPD2, SNRPE, SNRPF, and SNRPG are initially trapped in an inactive 6S pICln-Sm complex by the chaperone CLNS1A. The SMN complex accepts these proteins from CLNS1A to form an intermediate. SMN1 acts as the structural backbone of the SMN complex, while GEMIN2 gathers the Sm subunits. Binding of small nuclear RNA (snRNA) to the intermediate triggers the release of the SMN complex, allowing the addition of SNRPD3 and SNRPB to complete the core snRNP assembly.
The SMN complex ensures the proper splicing of U12 intron-containing genes, critical for motor and proprioceptive neuron development. It also resolves RNA-DNA hybrids (R-loops) formed by RNA polymerase II during transcription termination, ensuring proper transcriptional processes. Additionally, it may participate in the metabolism of small nucleolar ribonucleoproteins (snoRNPs), further contributing to RNA processing.
| Product Name | Recombinant Human SMN/Gemin 1 Protein (Tagged) |
| Accession | Q16637 |
| Host Species | Human |
| Gene | SMN1 |
| Source | E.coli |
