Seroatlas · Human Serome Atlas

CACNA1I

Voltage-dependent T-type calcium channel subunit alpha-1I

Also known as: CAC1I_HUMAN, Cav3.3

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

Protein identityUniProt · HPA

UniProt accession
Q9P0X4
Gene
CACNA1I
Ensembl
ENSG00000100346
Chromosome
22
Canonical length
2223 aa
Protein class
FDA approved drug targets, Plasma proteins, Predicted membrane proteins, Transporters, Voltage-gated ion channels
Subcellular location
Plasma membrane,Cell Junctions,Acrosome

OverviewNCBI Gene

This gene encodes the pore-forming alpha subunit of a voltage gated calcium channel. The encoded protein is a member of a subfamily of calcium channels referred to as is a low voltage-activated, T-type, calcium channel. The channel encoded by this protein is characterized by a slower activation and inactivation compared to other T-type calcium channels. This protein may be involved in calcium signaling in neurons. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Oct 2011]

Canonical amino-acid sequenceUniProt

2223 residues, UniProt reviewed canonical sequence.

>Q9P0X4|CACNA1I
     1  MAESASPPSS SAAAPAAEPG VTTEQPGPRS PPSSPPGLEE PLDGADPHVP HPDLAPIAFF
    61  CLRQTTSPRN WCIKMVCNPW FECVSMLVIL LNCVTLGMYQ PCDDMDCLSD RCKILQVFDD
   121  FIFIFFAMEM VLKMVALGIF GKKCYLGDTW NRLDFFIVMA GMVEYSLDLQ NINLSAIRTV
   181  RVLRPLKAIN RVPSMRILVN LLLDTLPMLG NVLLLCFFVF FIFGIIGVQL WAGLLRNRCF
   241  LEENFTIQGD VALPPYYQPE EDDEMPFICS LSGDNGIMGC HEIPPLKEQG RECCLSKDDV
   301  YDFGAGRQDL NASGLCVNWN RYYNVCRTGS ANPHKGAINF DNIGYAWIVI FQVITLEGWV
   361  EIMYYVMDAH SFYNFIYFIL LIIVGSFFMI NLCLVVIATQ FSETKQREHR LMLEQRQRYL
   421  SSSTVASYAE PGDCYEEIFQ YVCHILRKAK RRALGLYQAL QSRRQALGPE APAPAKPGPH
   481  AKEPRHYHGK TKGQGDEGRH LGSRHCQTLH GPASPGNDHS GRELCPQHSP LDATPHTLVQ
   541  PIPATLASDP ASCPCCQHED GRRPSGLGST DSGQEGSGSG SSAGGEDEAD GDGARSSEDG
   601  ASSELGKEEE EEEQADGAVW LCGDVWRETR AKLRGIVDSK YFNRGIMMAI LVNTVSMGIE
   661  HHEQPEELTN ILEICNVVFT SMFALEMILK LAAFGLFDYL RNPYNIFDSI IVIISIWEIV
   721  GQADGGLSVL RTFRLLRVLK LVRFMPALRR QLVVLMKTMD NVATFCMLLM LFIFIFSILG
   781  MHIFGCKFSL RTDTGDTVPD RKNFDSLLWA IVTVFQILTQ EDWNVVLYNG MASTSPWASL
   841  YFVALMTFGN YVLFNLLVAI LVEGFQAEGD ANRSYSDEDQ SSSNIEEFDK LQEGLDSSGD
   901  PKLCPIPMTP NGHLDPSLPL GGHLGPAGAA GPAPRLSLQP DPMLVALGSR KSSVMSLGRM
   961  SYDQRSLSSS RSSYYGPWGR SAAWASRRSS WNSLKHKPPS AEHESLLSAE RGGGARVCEV
  1021  AADEGPPRAA PLHTPHAHHI HHGPHLAHRH RHHRRTLSLD NRDSVDLAEL VPAVGAHPRA
  1081  AWRAAGPAPG HEDCNGRMPS IAKDVFTKMG DRGDRGEDEE EIDYTLCFRV RKMIDVYKPD
  1141  WCEVREDWSV YLFSPENRFR VLCQTIIAHK LFDYVVLAFI FLNCITIALE RPQIEAGSTE
  1201  RIFLTVSNYI FTAIFVGEMT LKVVSLGLYF GEQAYLRSSW NVLDGFLVFV SIIDIVVSLA
  1261  SAGGAKILGV LRVLRLLRTL RPLRVISRAP GLKLVVETLI SSLKPIGNIV LICCAFFIIF
  1321  GILGVQLFKG KFYHCLGVDT RNITNRSDCM AANYRWVHHK YNFDNLGQAL MSLFVLASKD
  1381  GWVNIMYNGL DAVAVDQQPV TNHNPWMLLY FISFLLIVSF FVLNMFVGVV VENFHKCRQH
  1441  QEAEEARRRE EKRLRRLEKK RRKAQRLPYY ATYCHTRLLI HSMCTSHYLD IFITFIICLN
  1501  VVTMSLEHYN QPTSLETALK YCNYMFTTVF VLEAVLKLVA FGLRRFFKDR WNQLDLAIVL
  1561  LSVMGITLEE IEINAALPIN PTIIRIMRVL RIARVLKLLK MATGMRALLD TVVQALPQVG
  1621  NLGLLFMLLF FIYAALGVEL FGKLVCNDEN PCEGMSRHAT FENFGMAFLT LFQVSTGDNW
  1681  NGIMKDTLRD CTHDERSCLS SLQFVSPLYF VSFVLTAQFV LINVVVAVLM KHLDDSNKEA
  1741  QEDAEMDAEL ELEMAHGLGP GPRLPTGSPG APGRGPGGAG GGGDTEGGLC RRCYSPAQEN
  1801  LWLDSVSLII KDSLEGELTI IDNLSGSIFH HYSSPAGCKK CHHDKQEVQL AETEAFSLNS
  1861  DRSSSILLGD DLSLEDPTAC PPGRKDSKGE LDPPEPMRVG DLGECFFPLS STAVSPDPEN
  1921  FLCEMEEIPF NPVRSWLKHD SSQAPPSPFS PDASSPLLPM PAEFFHPAVS ASQKGPEKGT
  1981  GTGTLPKIAL QGSWASLRSP RVNCTLLRQA TGSDTSLDAS PSSSAGSLQT TLEDSLTLSD
  2041  SPRRALGPPA PAPGPRAGLS PAARRRLSLR GRGLFSLRGL RAHQRSHSSG GSTSPGCTHH
  2101  DSMDPSDEEG RGGAGGGGAG SEHSETLSSL SLTSLFCPPP PPPAPGLTPA RKFSSTSSLA
  2161  APGRPHAAAL AHGLARSPSW AADRSKDPPG RAPLPMGLGP LAPPPQPLPG ELEPGDAASK
  2221  RKR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CACNA1I 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
24
Mean surface accessibility (rSASA)
0.44
Highest tissue expression
9.7 nTPM

Expression across tissuesHPA

Tissue

  • cerebellum: 9.7 nTPM
  • cerebral cortex: 9.5 nTPM
  • hippocampal formation: 6.5 nTPM
  • basal ganglia: 6.2 nTPM
  • thyroid gland: 5.1 nTPM
  • hypothalamus: 4.3 nTPM

Single-cell type

  • retinal amacrine cells: 107 nCPM
  • retinal bipolar cells: 33 nCPM
  • brain excitatory neurons: 26 nCPM
  • brain inhibitory neurons: 24 nCPM
  • other brain neurons: 11 nCPM
  • thymic myoid cells: 8.2 nCPM

Immune cell

  • naive CD4 T-cell: 0.3 nTPM
  • memory CD4 T-cell: 0.1 nTPM
  • naive CD8 T-cell: 0.1 nTPM
  • T-reg: 0.1 nTPM
  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM

Brain region

  • cerebral cortex: 35 nTPM
  • hippocampal formation: 33 nTPM
  • pons: 31 nTPM
  • basal ganglia: 26 nTPM
  • white matter: 24 nTPM
  • hypothalamus: 18 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CACNA1I.

Disease | AllUniProt

Conditions CACNA1I is implicated in, by any mechanism.

  • Neurodevelopmental disorder with speech impairment and with or without seizures (NEDSIS) MIM:620114

Disease | GeneticClinVar

6 pathogenic / likely-pathogenic of 600 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Neurodevelopmental disorder with speech impairment and with or without seizures

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
5.05
DepMap mean gene effect
0.01
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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 CACNA1I 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 CACNA1I as an antibody target. Whether an autoantibody or antibody against CACNA1I could matter depends on whether native CACNA1I is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CACNA1I is annotated at the cell surface, where native CACNA1I 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 CACNA1I as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CACNA1I. 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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