Seroatlas · Human Serome Atlas

SIPA1L3

Signal-induced proliferation-associated 1-like protein 3

Also known as: KIAA0545, SI1L3_HUMAN, SPAR3

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

Protein identityUniProt · HPA

UniProt accession
O60292
Gene
SIPA1L3
Ensembl
ENSG00000105738
Chromosome
19
Canonical length
1781 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Golgi apparatus,Plasma membrane

OverviewNCBI Gene

This gene belongs to the signal induced proliferation associated 1 family of genes, which encode GTPase-activating proteins specific for the GTP-binding protein Rap1. Rap1 has been implicated in regulation of cell adhesion, cell polarity, and organization of the cytoskeleton. Like other members of the family, the protein encoded by this gene contains RapGAP and PDZ domains. In addition, this protein contains a C-terminal leucine zipper domain. This gene is proposed to function in epithelial cell morphogenesis and establishment or maintenance of polarity. Consistently, expression of the protein in cell culture showed localization to cell-cell borders in apical regions, and downregulation of the gene in 3D Caco2 cell culture resulted in abnormal cell polarity and morphogenesis. Allelic variants of this gene have been associated with congenital cataracts in humans. [provided by RefSeq, Feb 2016]

Canonical amino-acid sequenceUniProt

1781 residues, UniProt reviewed canonical sequence.

>O60292|SIPA1L3
     1  MTTYRAIPSD GVDLAASCGA RVGDVLPGPH TGDYAPLGFW AQNGSMSQPL GESPATATAT
    61  ATATTRPSPT TPAMPKMGVR ARVADWPPKR EALREHSNPS PSQDTDGTKA TKMAHSMRSI
   121  QNGQPPTSTP ASSGSKAFHR LSRRRSKDVE FQDGWPRSPG RAFLPLRHRS SSEITLSECD
   181  AEDAGEPRGA RHTGALPLFR EYGSTSSIDV QGMPEQSFFD ILNEFRSEQP DARGCQALTE
   241  LLRADPGPHL MGGGGGAKGD SHNGQPAKDS LLPLQPTKEK EKARKKPARG LGGGDTVDSS
   301  IFRKLRSSKP EGEAGRSPGE ADEGRSPPEA SRPWVCQKSF AHFDVQSMLF DLNEAAANRV
   361  SVSQRRNTTT GASAASAASA MASLTASRAH SLGGLDPAFT STEDLNCKEN LEQDLGDDNS
   421  NDLLLSCPHF RNEIGGECER NVSFSRASVG SPSSGEGHLA EPALSAYRTN ASISVLEVPK
   481  EQQRTQSRPR QYSIEHVDLG ARYYQDYFVG KEHANYFGVD EKLGPVAVSI KREKLEDHKE
   541  HGPQYQYRII FRTRELITLR GSILEDATPT ATKHGTGRGL PLKDALEYVI PELNIHCLRL
   601  ALNTPKVTEQ LLKLDEQGLC RKHKVGILYC KAGQSSEEEM YNNEEAGPAF EEFLSLIGEK
   661  VCLKGFTKYA AQLDVKTDST GTHSLYTMYQ DYEIMFHVST LLPYTPNNRQ QLLRKRHIGN
   721  DIVTIIFQEP GALPFTPKNI RSHFQHVFII VRVHNPCTDN VCYSMAVTRS KDAPPFGPPI
   781  PSGTTFRKSD VFRDFLLAKV INAENAAHKS DKFHTMATRT RQEYLKDLAE NCVSNTPIDS
   841  TGKFNLISLT SKKKEKTKAR AGAEQHSAGA IAWRVVAQDY AQGVEIDCIL GISNEFVVLL
   901  DLRTKEVVFN CYCGDVIGWT PDSSTLKIFY GRGDHIFLQA TEGSVEDIRE IVQRLKVMTS
   961  GWETVDMTLR RNGLGQLGFH VKYDGTVAEV EDYGFAWQAG LRQGSRLVEI CKVAVVTLTH
  1021  DQMIDLLRTS VTVKVVIIPP FEDGTPRRGW PETYDMNTSE PKTEQESITP GGRPPYRSNA
  1081  PWQWSGPASH NSLPASKWAT PTTPGHAQSL SRPLKQTPIV PFRESQPLHS KRPVSFPETP
  1141  YTVSPAGADR VPPYRQPSGS FSTPGSATYV RYKPSPERYT AAPHPLLSLD PHFSHDGTSS
  1201  GDSSSGGLTS QESTMERQKP EPLWHVPAQA RLSAIAGSSG NKHPSRQDAA GKDSPNRHSK
  1261  GEPQYSSHSS SNTLSSNASS SHSDDRWFDP LDPLEPEQDP LSKGGSSDSG IDTTLYTSSP
  1321  SCMSLAKAPR PAKPHKPPGS MGLCGGGREA AGRSHHADRR REVSPAPAVA GQSKGYRPKL
  1381  YSSGSSTPTG LAGGSRDPPR QPSDMGSRVG YPAQVYKTAS AETPRPSQLA QPSPFQLSAS
  1441  VPKSFFSKQP VRNKHPTGWK RTEEPPPRPL PFSDPKKQVD TNTKNVFGQP RLRASLRDLR
  1501  SPRKNYKSTI EDDLKKLIIM DNLGPEQERD TGQSPQKGLQ RTLSDESLCS GRREPSFASP
  1561  AGLEPGLPSD VLFTSTCAFP SSTLPARRQH QHPHPPVGPG ATPAAGSGFP EKKSTISASE
  1621  LSLADGRDRP LRRLDPGLMP LPDTAAGLEW SSLVNAAKAY EVQRAVSLFS LNDPALSPDI
  1681  PPAHSPVHSH LSLERGPPTP RTTPTMSEEP PLDLTGKVYQ LEVMLKQLHT DLQKEKQDKV
  1741  VLQSEVASLR QNNQRLQEES QAASEQLRKF AEIFCREKKE L

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SIPA1L3 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
Cell surface
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.53
Highest tissue expression
17 nTPM

Expression across tissuesHPA

Tissue

  • duodenum: 17 nTPM
  • small intestine: 17 nTPM
  • skin: 11 nTPM
  • colon: 9.9 nTPM
  • thyroid gland: 9.4 nTPM
  • pancreas: 9.2 nTPM

Single-cell type

  • retinal amacrine cells: 1,039 nCPM
  • retinal horizontal cells: 527 nCPM
  • pancreatic islet cells: 470 nCPM
  • enterocytes: 468 nCPM
  • proximal tubule cells: 463 nCPM
  • b-cells: 442 nCPM

Immune cell

  • naive B-cell: 1.5 nTPM
  • non-classical monocyte: 1.5 nTPM
  • memory B-cell: 1.1 nTPM
  • eosinophil: 0.5 nTPM
  • naive CD8 T-cell: 0.5 nTPM
  • NK-cell: 0.3 nTPM

Brain region

  • hippocampal formation: 77 nTPM
  • cerebral cortex: 50 nTPM
  • cerebellum: 39 nTPM
  • amygdala: 30 nTPM
  • thalamus: 30 nTPM
  • white matter: 28 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SIPA1L3.

Disease | AllUniProt

Conditions SIPA1L3 is implicated in, by any mechanism.

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 599 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Cataract 45

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)
0.2
gnomAD pLI
1
gnomAD missense Z
1.55
DepMap mean gene effect
0.02
DepMap dependency class
selective

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

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of SIPA1L3 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 SIPA1L3 as an antibody target. Whether an autoantibody or antibody against SIPA1L3 could matter depends on whether native SIPA1L3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SIPA1L3 is annotated at the cell surface, where native SIPA1L3 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label SIPA1L3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SIPA1L3. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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