Protein / target
Survival motor neuron protein
Protein at a glance
Biological role
Identical protein binding
Primary system
Nervous system
Strongest disease association
spinal muscular atrophy, type III
Therapeutic maturity
Clinically validated target
Druggability
Small molecule
Clinical development
1 approved
Derived from structured UniProt, Open Targets and literature data on this page.
Protein profile
Canonical identity and biological annotation from UniProt.
Function
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:9845364). 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 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 forming an intermediate (PubMed:18984161). Within the SMN complex, SMN1 acts as a structural backbone and together with GEMIN2 it gathers the Sm complex subunits (PubMed:17178713, PubMed:21816274, PubMed:22101937). 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). Ensures the correct splicing of U12 intron-containing genes that may be important for normal motor and proprioceptive neurons development (PubMed:23063131). Also required for resolving RNA-DNA hybrids created by RNA polymerase II, that form R-loop in transcription terminal regions, an important step in proper transcription termination (PubMed:26700805). May also play a role in the metabolism of small nucleolar ribonucleoprotein (snoRNPs)
Subcellular location
Domains and Gene Ontology detail (21)Hide
Domains & features
Gene Ontology
- Caxon
- CCajal body
- Ccytoplasm
- Ccytoplasmic ribonucleoprotein granule
- Ccytosol
- CGemini of Cajal bodies
- Cneuron projection
- Cnuclear body
- Cnucleoplasm
- Cnucleus
- Cperikaryon
- CSMN complex
Biological roles
What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.
View supporting evidenceHide supporting evidence
Transcriptional regulation
- ·The SMN complex catalyzes the assembly of small nuclear ribonucleoproteins (snRNPs), the…
- ·DNA-templated transcription termination
Muscle contraction
- ·Cytoplasm, myofibril, sarcomere, Z line
View underlying pathways (2)Hide underlying pathways
Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.
Interaction neighbourhood
Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.
Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.
Drugs targeting this protein
Whether each drug engages this protein directly or through a complex, and how many other targets are recorded for it. Direct binders with few recorded targets are listed first.
Survival motor neuron protein exogenous gene
Appears in clinical studies involving spinal muscular atrophy, spinal muscular atrophy, proximal spinal muscular atrophy, spinal muscular atrophy, type 1
ChEMBL mechanism, action type and target identity. Open Targets clinical status and indications.
Translational evidence
Why this target matters therapeutically — disease associations, drugs in development, tractability and safety, from Open Targets.
Strongest genetic associations
Human genetic evidence — the most direct causal link between this target and a disease.
Highest-confidence therapeutic associations
Diseases where a drug acting on this target has already reached clinical development.
Highest overall evidence
Remaining associations by Open Targets' aggregated evidence score.
Show all associationsHide all associations
Open Targets ranks 1,592 associations for this target and we store the top 10 by aggregated score. The long tail is largely literature co-mention and RNA-expression evidence, not evidence that this target drives those diseases.
Known drugs · 1 total
spinal muscular atrophy · spinal muscular atrophy · proximal spinal muscular atrophy
Tractability
Clinical trials
Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein.
ClinicalTrials.gov via the drug-target graph.
Forefront confidence
Our own weighting of the evidence behind each disease association. Human genetics and clinical evidence count for most; literature co-mention counts for little, because two entities sharing an abstract is not evidence that one drives the other.
This ranking differs from Open Targets' own: re-weighting moves genetically-evidenced diseases above more heavily co-mentioned ones. The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the underlying per-type scores are shown above so the calculation can be checked.
What's happening now
Recent activity around this target, drawn from one canonical event stream. Every item is reached through a drug that targets this protein, so each event is news about that drug rather than about the protein directly.
- Regulatory approval
Approval: Itvisma (EMA)
- CHMP positive opinion
CHMP positive opinion: Itvisma (EMA)
- New publicationHepatotoxicity following administration of onasemnogene abeparvovec (AVXS-101) for the treatment of spinal muscular atrophy.
- Regulatory approval
Approval: Zolgensma (EMA)
Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.