UniProt Summary: Chaperone that regulates the assembly of spliceosomal U1, U2, U4 and U5 small nuclear ribonucleoproteins (snRNPs), the building blocks of the spliceosome. Thereby, plays an important role in the splicing of cellular pre-mRNAs. 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. In the cytosol, the Sm proteins SNRPD1, SNRPD2, SNRPE, SNRPF and SNRPG are trapped in an inactive 6S pICln-Sm complex by the chaperone CLNS1A that controls the assembly of the core snRNP. Dissociation by the SMN complex of CLNS1A from the trapped Sm proteins and their transfer to an SMN-Sm complex triggers the assembly of core snRNPs and their transport to the nucleus. May also indirectly participate in cellular volume control by activation of a swelling-induced chloride conductance pathway. {ECO:0000269|PubMed:10330151, ECO:0000269|PubMed:11713266, ECO:0000269|PubMed:18984161}.
Pfam DomainsGO Terms
Pfam Domains
ICln channel
GO Terms
pICln-Sm protein complex
methylosome
cell volume homeostasis
spliceosomal snRNP assembly
chloride transport
inorganic anion transport
regulation of cell size
ribonucleoprotein complex assembly
ribonucleoprotein complex subunit organization
RNA splicing, via transesterification reactions with bulged adenosine as nucleophile
mRNA splicing, via spliceosome
RNA splicing, via transesterification reactions
cytoskeleton
regulation of cellular component size
RNA splicing
ribonucleoprotein complex biogenesis
mRNA processing
protein heterodimerization activity
regulation of anatomical structure size
anion transport
mRNA metabolic process
cellular protein-containing complex assembly
RNA processing
cellular homeostasis
ion transport
RNA binding
protein-containing complex assembly
homeostatic process
RNA metabolic process
protein-containing complex subunit organization
gene expression
CRISPR Data
Compound HitMost Correlated Genes in ChemogenomicsTissues where Essential in the Avana Dataset (DepMap 20Q1)