FEATURES

FAMILY

DESCRIPTION

Also known as GEMI2_HUMAN, GEMIN2, SIP1. The SMN complex catalyzes the assembly of small nuclear ribonucleoproteins (snRNPs), the building blocks of the spliceosome, and thereby plays an important role in the splicing of cellular pre-mRNAs (PubMed:18984161, PubMed:9323129). Most spliceosomal snRNPs contain a common set of Sm proteins SNRPB, SNRPD1, SNRPD2, SNRPD3, SNRPE, SNRPF and SNRPG that assemble in a heptameric protein ring on the Sm site of the small nuclear RNA to form the core snRNP (Sm core) (PubMed:18984161). In the cytosol, the Sm proteins SNRPD1, SNRPD2, SNRPE, SNRPF and SNRPG (5Sm) are trapped in an inactive 6S pICln-Sm complex by the chaperone CLNS1A that controls the assembly of the core snRNP (PubMed:18984161). To assemble core snRNPs, the SMN complex accepts the trapped 5Sm proteins from CLNS1A (PubMed:18984161, PubMed:9323129). Binding of snRNA inside 5Sm ultimately triggers eviction of the SMN complex, thereby allowing binding of SNRPD3 and SNRPB to complete assembly of the core snRNP (PubMed:31799625). Within the SMN complex, GEMIN2 constrains the conformation of 5Sm, thereby promoting 5Sm binding to snRNA containing the snRNP code (a nonameric Sm site and a 3'-adjacent stem-loop), thus preventing progression of assembly until a cognate substrate is bound (PubMed:31799625, PubMed:21816274, PubMed:16314521). Monomer (PubMed:26092730). Part of the core SMN complex that contains SMN1, GEMIN2/SIP1, DDX20/GEMIN3, GEMIN4, GEMIN5, GEMIN6, GEMIN7, GEMIN8 and STRAP/UNRIP (PubMed:11714716, PubMed:9323129, PubMed:16314521, PubMed:17178713). Part of the SMN-Sm complex that contains SMN1, GEMIN2/SIP1, DDX20/GEMIN3, GEMIN4, GEMIN5, GEMIN6, GEMIN7, GEMIN8, STRAP/UNRIP and the Sm proteins SNRPB, SNRPD1, SNRPD2, SNRPD3, SNRPE, SNRPF and SNRPG (PubMed:18984161, PubMed:9323129, PubMed:16314521). Interacts with GEMIN5; the interaction is direct (PubMed:11714716). Interacts (via C-terminus) with SMN1; the interaction is direct (PubMed:21816274, PubMed:26092730, PubMed:10500148, PubMed:31799625, PubMed:17178713, PubMed:22607171, PubMed:23022347). Interacts with GEMIN5; the interaction is direct (PubMed:17178713). Interacts with SNRPD1; the interaction is direct (PubMed:21816274, PubMed:31799625). Interacts with SNRPD2; the interaction is direct (PubMed:21816274, PubMed:31799625). Interacts (via N-terminus) with SNRPF; the interaction is direct (PubMed:21816274, PubMed:31799625). Interacts (via N-terminus) with SNRPE; the interaction is direct (PubMed:21816274, PubMed:31799625). Interacts (via N-terminus) with SNRPG; the interaction is direct (PubMed:21816274).

EXTERNAL LINKS

GEMIN2

Gem-associated protein 2

GEMIN2

Molecular Synopsis