A large macromolecular complex (survival of motor neurons complex) that plays an essential role in the production of spliceosomal small nuclear ribonucleoproteins (snRNPs). It is present in both cytoplasm and nucleus, and is enriched in Gems (gemini of the coiled bodies), nuclear structures that resemble Cajal bodies in number and size. At least seven gemins are components, as well as the product of the survival of motor neurons (SMN) gene (defective in spinal muscular atrophy). SMN complex substrates have a domain rich in arginine and glycine residues (RG) and include Sm and Sm-like (LSm) proteins, RNA helicase A, fibrillarin, the RNP proteins, and p80-*coilin.
Subjects: Medicine and Health.