Seroatlas · Human Serome Atlas

SF3B2

Splicing factor 3B subunit 2

Also known as: Cus1, SAP145, SF3b1, SF3b145, SF3B2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession: Q13435
Gene: SF3B2
Ensembl: ENSG00000087365
Chromosome: 11
Canonical length: 895 aa
Protein class: Disease related genes, Plasma proteins, Predicted intracellular proteins
Subcellular location: Nuclear speckles

OverviewNCBI Gene

This gene encodes subunit 2 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. Subunit 2 associates with pre-mRNA upstream of the branch site at the anchoring site. Subunit 2 also interacts directly with subunit 4 of the splicing factor 3b complex. Subunit 2 is a highly hydrophilic protein with a proline-rich N-terminus and a glutamate-rich stretch in the C-terminus. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

895 residues, UniProt reviewed canonical sequence.

>Q13435|SF3B2
     1  MATEHPEPPK AELQLPPPPP PGHYGAWAAQ ELQAKLAEIG APIQGNREEL VERLQSYTRQ
    61  TGIVLNRPVL RGEDGDKAAP PPMSAQLPGI PMPPPPLGLP PLQPPPPPPP PPPGLGLGFP
   121  MAHPPNLGPP PPLRVGEPVA LSEEERLKLA QQQAALLMQQ EERAKQQGDH SLKEHELLEQ
   181  QKRAAVLLEQ ERQQEIAKMG TPVPRPPQDM GQIGVRTPLG PRVAAPVGPV GPTPTVLPMG
   241  APVPRPRGPP PPPGDENREM DDPSVGPKIP QALEKILQLK ESRQEEMNSQ QEEEEMETDA
   301  RSSLGQSASE TEEDTVSVSK KEKNRKRRNR KKKKKPQRVR GVSSESSGDR EKDSTRSRGS
   361  DSPAADVEIE YVTEEPEIYE PNFIFFKRIF EAFKLTDDVK KEKEKEPEKL DKLENSAAPK
   421  KKGFEEEHKD SDDDSSDDEQ EKKPEAPKLS KKKLRRMNRF TVAELKQLVA RPDVVEMHDV
   481  TAQDPKLLVH LKATRNSVPV PRHWCFKRKY LQGKRGIEKP PFELPDFIKR TGIQEMREAL
   541  QEKEEQKTMK SKMREKVRPK MGKIDIDYQK LHDAFFKWQT KPKLTIHGDL YYEGKEFETR
   601  LKEKKPGDLS DELRISLGMP VGPNAHKVPP PWLIAMQRYG PPPSYPNLKI PGLNSPIPES
   661  CSFGYHAGGW GKPPVDETGK PLYGDVFGTN AAEFQTKTEE EEIDRTPWGE LEPSDEESSE
   721  EEEEEESDED KPDETGFITP ADSGLITPGG FSSVPAGMET PELIELRKKK IEEAMDGSET
   781  PQLFTVLPEK RTATVGGAMM GSTHIYDMST VMSRKGPAPE LQGVEVALAP EELELDPMAM
   841  TQKYEEHVRE QQAQVEKEDF SDMVAEHAAK QKQKKRKAQP QDSRGGSKKY KEFKF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SF3B2 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): 0.58
Highest tissue expression: 169 nTPM

Expression across tissuesHPA

Tissue

choroid plexus: 169 nTPM
bone marrow: 136 nTPM
pituitary gland: 132 nTPM
testis: 132 nTPM
blood vessel: 128 nTPM
ovary: 126 nTPM

Single-cell type

late primary spermatocytes: 462 nCPM
extravillous trophoblasts: 257 nCPM
cytotrophoblasts: 244 nCPM
early spermatids: 238 nCPM
migrating cytotrophoblasts: 237 nCPM
syncytiotrophoblasts: 230 nCPM

Immune cell

eosinophil: 168 nTPM
non-classical monocyte: 161 nTPM
basophil: 153 nTPM
total PBMC: 148 nTPM
gdT-cell: 136 nTPM
T-reg: 132 nTPM

Brain region

white matter: 142 nTPM
cerebral cortex: 126 nTPM
basal ganglia: 123 nTPM
choroid plexus: 122 nTPM
thalamus: 122 nTPM
medulla oblongata: 120 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SF3B2.

Disease | AllUniProt

Conditions SF3B2 is implicated in, by any mechanism.

Craniofacial microsomia 1 (CFM1) MIM:164210

Disease | GeneticClinVar

9 pathogenic / likely-pathogenic of 146 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

Craniofacial microsomia 1

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): 0.22
gnomAD pLI: 1
gnomAD missense Z: 3.68
DepMap mean gene effect: -1.36
DepMap dependency class: pan

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 8% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

RNA binding

Cellular components

Protein domainsUniProt · Pfam · InterPro

SAP domain
PSP, proline-rich
SAP domain
PSP
Domain of unknown function DUF382
Pre-mRNA Spliceosomal U2 snRNP Complex Component
Domain of unknown function (DUF382)

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of SF3B2 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 SF3B2 as an antibody target. Whether an autoantibody or antibody against SF3B2 could matter depends on whether native SF3B2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SF3B2 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 SF3B2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...