Seroatlas · Human Serome Atlas

SF3B1

Splicing factor 3B subunit 1

Also known as: Hsh155, Prp10, PRPF10, SAP155, SF3B1_HUMAN, SF3b155

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession: O75533
Gene: SF3B1
Ensembl: ENSG00000115524
Chromosome: 2
Canonical length: 1304 aa
Protein class: Cancer-related genes, Human disease related genes, Plasma proteins, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location: Nuclear speckles

OverviewNCBI Gene

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]

Canonical amino-acid sequenceUniProt

1304 residues, UniProt reviewed canonical sequence.

>O75533|SF3B1
     1  MAKIAKTHED IEAQIREIQG KKAALDEAQG VGLDSTGYYD QEIYGGSDSR FAGYVTSIAA
    61  TELEDDDDDY SSSTSLLGQK KPGYHAPVAL LNDIPQSTEQ YDPFAEHRPP KIADREDEYK
   121  KHRRTMIISP ERLDPFADGG KTPDPKMNAR TYMDVMREQH LTKEEREIRQ QLAEKAKAGE
   181  LKVVNGAAAS QPPSKRKRRW DQTADQTPGA TPKKLSSWDQ AETPGHTPSL RWDETPGRAK
   241  GSETPGATPG SKIWDPTPSH TPAGAATPGR GDTPGHATPG HGGATSSARK NRWDETPKTE
   301  RDTPGHGSGW AETPRTDRGG DSIGETPTPG ASKRKSRWDE TPASQMGGST PVLTPGKTPI
   361  GTPAMNMATP TPGHIMSMTP EQLQAWRWER EIDERNRPLS DEELDAMFPE GYKVLPPPAG
   421  YVPIRTPARK LTATPTPLGG MTGFHMQTED RTMKSVNDQP SGNLPFLKPD DIQYFDKLLV
   481  DVDESTLSPE EQKERKIMKL LLKIKNGTPP MRKAALRQIT DKAREFGAGP LFNQILPLLM
   541  SPTLEDQERH LLVKVIDRIL YKLDDLVRPY VHKILVVIEP LLIDEDYYAR VEGREIISNL
   601  AKAAGLATMI STMRPDIDNM DEYVRNTTAR AFAVVASALG IPSLLPFLKA VCKSKKSWQA
   661  RHTGIKIVQQ IAILMGCAIL PHLRSLVEII EHGLVDEQQK VRTISALAIA ALAEAATPYG
   721  IESFDSVLKP LWKGIRQHRG KGLAAFLKAI GYLIPLMDAE YANYYTREVM LILIREFQSP
   781  DEEMKKIVLK VVKQCCGTDG VEANYIKTEI LPPFFKHFWQ HRMALDRRNY RQLVDTTVEL
   841  ANKVGAAEII SRIVDDLKDE AEQYRKMVME TIEKIMGNLG AADIDHKLEE QLIDGILYAF
   901  QEQTTEDSVM LNGFGTVVNA LGKRVKPYLP QICGTVLWRL NNKSAKVRQQ AADLISRTAV
   961  VMKTCQEEKL MGHLGVVLYE YLGEEYPEVL GSILGALKAI VNVIGMHKMT PPIKDLLPRL
  1021  TPILKNRHEK VQENCIDLVG RIADRGAEYV SAREWMRICF ELLELLKAHK KAIRRATVNT
  1081  FGYIAKAIGP HDVLATLLNN LKVQERQNRV CTTVAIAIVA ETCSPFTVLP ALMNEYRVPE
  1141  LNVQNGVLKS LSFLFEYIGE MGKDYIYAVT PLLEDALMDR DLVHRQTASA VVQHMSLGVY
  1201  GFGCEDSLNH LLNYVWPNVF ETSPHVIQAV MGALEGLRVA IGPCRMLQYC LQGLFHPARK
  1261  VRDVYWKIYN SIYIGSQDAL IAHYPRIYND DKNTYIRYEL DYIL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SF3B1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability: Intracellular
Secreted: No
Transmembrane segments: 0
Mean surface accessibility (rSASA): 0.38
Highest tissue expression: 288 nTPM

Expression across tissuesHPA

Tissue

bone marrow: 288 nTPM
spleen: 230 nTPM
thymus: 207 nTPM
lymph node: 190 nTPM
epididymis: 189 nTPM
tonsil: 187 nTPM

Single-cell type

neutrophils: 495 nCPM
neutrophil progenitors: 284 nCPM
monocyte progenitors: 250 nCPM
monocytes: 246 nCPM
erythrocyte progenitors: 226 nCPM
innate lymphoid cells: 208 nCPM

Immune cell

T-reg: 72 nTPM
neutrophil: 61 nTPM
myeloid DC: 61 nTPM
eosinophil: 58 nTPM
NK-cell: 57 nTPM
total PBMC: 56 nTPM

Brain region

choroid plexus: 173 nTPM
white matter: 162 nTPM
cerebellum: 136 nTPM
basal ganglia: 118 nTPM
medulla oblongata: 117 nTPM
spinal cord: 110 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SF3B1.

Disease | GeneticClinVar

4 pathogenic / likely-pathogenic of 98 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance): 0.07
gnomAD pLI: 1
gnomAD missense Z: 7.7
DepMap mean gene effect: -1.5
DepMap dependency class: pan

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

Armadillo-like helical
Armadillo-type fold
Phosphatase PP2A regulatory subunit A/Splicing factor 3B subunit 1-like, HEAT repeat
PPP2R1A-like HEAT repeat
Splicing factor 3B subunit 1
Splicing factor 3B subunit 1-like
Splicing factor 3B subunit 1

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of SF3B1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SF3B1 as an antibody target. Whether an autoantibody or antibody against SF3B1 could matter depends on whether native SF3B1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SF3B1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label SF3B1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...