SF3B1 Splicing factor 3b subunit 1 O75533 SF3B1_HUMAN
Protein Coding Chr 2 2q33.1 Swiss-Prot reviewed Entrez 23451
Mutations
1,458
CL 131 · Tissue 1,304
Samples
1,160
CL 98 · Tissue 1,048
Peptides
519
unique mutant peptides
Transcripts
4
isoforms mutated

Stats by Source

Global, split by cell line (COSMIC CL / DepMap / PubMed) vs tissue (COSMIC primary tissue)

How the counts split by source
Stats by Source

Global = all mutations for this gene across every source.

Cell line = COSMIC Cell Lines Project + DepMap + PubMed.

Tissue = COSMIC primary-tissue (patient tumour) samples.

Global can exceed cell line + tissue: COSMIC tissue-derived models sit only in global, and a peptide can be shared across both.

GlobalCell lineTissue
Mutations1,4581311,304
Samples1,160981,048
Peptides51964468

Function

SF3B1 · Splicing factor 3b subunit 1

This gene encodes subunit 1 of the splicing factor 3b protein complex. Splicing factor 3b, together with splicing factor 3a and a 12S RNA unit, forms the U2 small nuclear ribonucleoproteins complex (U2 snRNP). The splicing factor 3b/3a complex binds pre-mRNA upstream of the intron's branch site in a sequence independent manner and may anchor the U2 snRNP to the pre-mRNA. Splicing factor 3b is also a component of the minor U12-type spliceosome. The carboxy-terminal two-thirds of subunit 1 have 22 non-identical, tandem HEAT repeats that form rod-like, helical structures. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jul 2008].

Isoforms & Proteins

4 transcripts · UniProt mapping is sequence-verified (AA-safe)

About the isoform mapping
Isoforms & Proteins

Each Ensembl transcript (ENST) this gene is mutated on, with its matched UniProt accession.

The mapping is sequence-verified: the UniProt sequence is identical to the transcript translation, so amino-acid positions line up exactly. A * marks an unreviewed (TrEMBL) entry.

Counts are mutations and unique mutant peptides on each transcript.

TranscriptUniProtMutationsPeptides
ENST00000335508 O75533 1,261 505
ENST00000487698 A0A494C0N7* 67 59
ENST00000409915 O75533-2 65 57
ENST00000414963 O75533-2 65 57

Gene Properties

Type
Protein Coding
Chromosome
2
Cytoband
2q33.1
Entrez ID
Aliases
Hsh155MDSPRP10PRPF10SAP155SF3b155

Recurrent Mutations

Top recurrent amino-acid changes along the protein · needle height = number of mutations

What this lollipop shows
Recurrent Mutations

A lollipop / needle plot – the standard way to show recurrent mutations along a protein (as used by cBioPortal and MutationMapper).

X-axis = amino-acid position in the protein.

Needle height & head size = how often that exact amino-acid change was observed (its recurrence). Tall/large heads are mutational hotspots.

The most recurrent changes are labelled; hover any needle for the change, position and counts.

Mutation Distribution

Where SF3B1 is mutated · all tissues, split by cell line vs tissue

Mutation counts by tissue
Mutation Distribution

How many mutations in SF3B1 were found in each tissue, across the whole database.

Each bar is a tissue (cell-line and tissue names are merged to the standard tissue), split into cell line and tissue (patient tumour) contributions.

This shows the cancer-context where this gene is recurrently altered.

GTEx Expression

Median TPM across 54 healthy tissues

GTEx Portal ↗
About the expression data
GTEx Expression

Median gene expression (TPM) in normal, non-cancer human tissues from the GTEx project.

Useful for judging tumour specificity – a strong neoantigen target ideally comes from a gene with low expression in healthy tissues.

Scroll or drag the mini-axis below the chart to browse all tissues.

Mutations

All 1,458 mutations in SF3B1

About the mutation list
Mutations

Every mutation record for this gene, across all samples and sources.

The Sample column links to the cell line (cell-line samples) or the tissue type (tissue samples).

Use the Type / Source filters, the search box, and column sorting to explore; each CAN-IMMUNE ID opens the full mutation & peptide view.

IDSampleTranscriptAA Change CDSTypeSourcePeptide