O43497 (CAC1G_HUMAN) Reviewed, UniProtKB/Swiss-Prot
Last modified
May 1, 2013.
Version 115.
History...
Names·Attributes·General annotation·Ontologies·Alt products·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order
Names·Attributes·General annotation·Ontologies·Alt products·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize orderNames and origin
| Protein names | Recommended name: Voltage-dependent T-type calcium channel subunit alpha-1G Alternative name(s): Cav3.1c NBR13 Voltage-gated calcium channel subunit alpha Cav3.1 | ||||
| Gene names |
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| Organism | Homo sapiens (Human) [Reference proteome] | ||||
| Taxonomic identifier | 9606 [NCBI] | ||||
| Taxonomic lineage | Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo![]() |
Protein attributes
| Sequence length | 2377 AA. |
| Sequence status | Complete. |
| Protein existence | Evidence at transcript level |
General annotation (Comments)
| Function | Voltage-sensitive calcium channels (VSCC) mediate the entry of calcium ions into excitable cells and are also involved in a variety of calcium-dependent processes, including muscle contraction, hormone or neurotransmitter release, gene expression, cell motility, cell division and cell death. The isoform alpha-1G gives rise to T-type calcium currents. T-type calcium channels belong to the "low-voltage activated (LVA)" group and are strongly blocked by mibefradil. A particularity of this type of channels is an opening at quite negative potentials and a voltage-dependent inactivation. T-type channels serve pacemaking functions in both central neurons and cardiac nodal cells and support calcium signaling in secretory cells and vascular smooth muscle. They may also be involved in the modulation of firing patterns of neurons which is important for information processing as well as in cell growth processes. |
| Subcellular location | |
| Tissue specificity | Highly expressed in brain, in particular in the amygdala, subthalamic nuclei, cerebellum and thalamus. Moderate expression in heart; low expression in placenta, kidney and lung. Also expressed in colon and bone marrow and in tumoral cells to a lesser extent. Highly expressed in fetal brain, but also in peripheral fetal tissues as heart, kidney and lung, suggesting a developmentally regulated expression. |
| Domain | Each of the four internal repeats contains five hydrophobic transmembrane segments (S1, S2, S3, S5, S6) and one positively charged transmembrane segment (S4). S4 segments probably represent the voltage-sensor and are characterized by a series of positively charged amino acids at every third position. The linker region between repeat III and IV probably play a role in the inactivation of the channel. The C-terminal part may be implicated in the anchoring of the protein to the membrane, this by interfering/restricting its lateral diffusion. |
| Post-translational modification | In response to raising of intracellular calcium, the T-type channels are activated by CaM-kinase II. |
| Sequence similarities | Belongs to the calcium channel alpha-1 subunit (TC 1.A.1.11) family. CACNA1G subfamily. [View classification] |
Ontologies
Alternative products
| This entry describes 13 isoforms produced by alternative splicing. [Align] [Select] Note: Additional isoforms seem to exist. | ||||||
| Isoform 5 (identifier: O43497-1) This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry. | ||||||
| Isoform 1 (identifier: O43497-2) The sequence of this isoform differs from the canonical sequence as follows: 971-993: Missing. 1569-1586: NLMLDDVIASGSSASAAS → SKEKQMA 1928-2020: Missing. | ||||||
| Isoform 2 (identifier: O43497-3) The sequence of this isoform differs from the canonical sequence as follows: 971-993: Missing. 1569-1587: NLMLDDVIASGSSASAASE → K 1928-2020: Missing. | ||||||
| Isoform 3 (identifier: O43497-4) The sequence of this isoform differs from the canonical sequence as follows: 971-993: Missing. | ||||||
| Isoform 4 (identifier: O43497-5) The sequence of this isoform differs from the canonical sequence as follows: 971-993: Missing. 1569-1586: NLMLDDVIASGSSASAAS → SKEKQMA 1928-2020: Missing. 2156-2234: Missing. | ||||||
| Isoform 6 (identifier: O43497-6) The sequence of this isoform differs from the canonical sequence as follows: 1569-1586: NLMLDDVIASGSSASAAS → SKEKQMA 1928-2020: Missing. | ||||||
| Isoform 7 (identifier: O43497-7) The sequence of this isoform differs from the canonical sequence as follows: 1569-1586: NLMLDDVIASGSSASAAS → SKEKQMA 1976-2020: Missing. | ||||||
| Isoform 8 (identifier: O43497-8) The sequence of this isoform differs from the canonical sequence as follows: 971-993: Missing. 1569-1586: NLMLDDVIASGSSASAAS → SKEKQMA 1976-2020: Missing. | ||||||
| Isoform 9 (identifier: O43497-9) The sequence of this isoform differs from the canonical sequence as follows: 971-993: Missing. 1928-2020: Missing. | ||||||
| Isoform 10 (identifier: O43497-10) The sequence of this isoform differs from the canonical sequence as follows: 971-993: Missing. 1928-1975: Missing. | ||||||
| Isoform 11 (identifier: O43497-11) The sequence of this isoform differs from the canonical sequence as follows: 1928-2020: Missing. | ||||||
| Isoform 12 (identifier: O43497-12) The sequence of this isoform differs from the canonical sequence as follows: 1976-2020: Missing. | ||||||
| Isoform 13 (identifier: O43497-13) The sequence of this isoform differs from the canonical sequence as follows: 1569-1587: NLMLDDVIASGSSASAASE → K 1928-2020: Missing. |
Sequence annotation (Features)
| Feature key | Position(s) | Length | Description | Graphical view | Feature identifier | ||||
Molecule processing | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Chain | 1 – 2377 | 2377 | Voltage-dependent T-type calcium channel subunit alpha-1G | PRO_0000053952 | |||||
Regions | |||||||||
| Topological domain | 1 – 80 | 80 | Cytoplasmic Potential | ||||||
| Transmembrane | 81 – 101 | 21 | Helical; Name=S1 of repeat I; Potential | ||||||
| Topological domain | 102 – 119 | 18 | Extracellular Potential | ||||||
| Transmembrane | 120 – 141 | 22 | Helical; Name=S2 of repeat I; Potential | ||||||
| Topological domain | 142 – 150 | 9 | Cytoplasmic Potential | ||||||
| Transmembrane | 151 – 170 | 20 | Helical; Name=S3 of repeat I; Potential | ||||||
| Topological domain | 171 – 175 | 5 | Extracellular Potential | ||||||
| Transmembrane | 176 – 193 | 18 | Helical; Name=S4 of repeat I; Potential | ||||||
| Topological domain | 194 – 213 | 20 | Cytoplasmic Potential | ||||||
| Transmembrane | 214 – 234 | 21 | Helical; Name=S5 of repeat I; Potential | ||||||
| Topological domain | 235 – 370 | 136 | Extracellular Potential | ||||||
| Transmembrane | 371 – 395 | 25 | Helical; Name=S6 of repeat I; Potential | ||||||
| Topological domain | 396 – 743 | 348 | Cytoplasmic Potential | ||||||
| Transmembrane | 744 – 764 | 21 | Helical; Name=S1 of repeat II; Potential | ||||||
| Topological domain | 765 – 777 | 13 | Extracellular Potential | ||||||
| Transmembrane | 778 – 799 | 22 | Helical; Name=S2 of repeat II; Potential | ||||||
| Topological domain | 800 – 805 | 6 | Cytoplasmic Potential | ||||||
| Transmembrane | 806 – 824 | 19 | Helical; Name=S3 of repeat II; Potential | ||||||
| Topological domain | 825 – 832 | 8 | Extracellular Potential | ||||||
| Transmembrane | 833 – 856 | 24 | Helical; Name=S4 of repeat II; Potential | ||||||
| Topological domain | 857 – 867 | 11 | Cytoplasmic Potential | ||||||
| Transmembrane | 868 – 888 | 21 | Helical; Name=S5 of repeat II; Potential | ||||||
| Topological domain | 889 – 939 | 51 | Extracellular Potential | ||||||
| Transmembrane | 940 – 964 | 25 | Helical; Name=S6 of repeat II; Potential | ||||||
| Topological domain | 965 – 1272 | 308 | Cytoplasmic Potential | ||||||
| Transmembrane | 1273 – 1295 | 23 | Helical; Name=S1 of repeat III; Potential | ||||||
| Topological domain | 1296 – 1313 | 18 | Extracellular Potential | ||||||
| Transmembrane | 1314 – 1334 | 21 | Helical; Name=S2 of repeat III; Potential | ||||||
| Topological domain | 1335 – 1344 | 10 | Cytoplasmic Potential | ||||||
| Transmembrane | 1345 – 1364 | 20 | Helical; Name=S3 of repeat III; Potential | ||||||
| Topological domain | 1365 – 1378 | 14 | Extracellular Potential | ||||||
| Transmembrane | 1379 – 1400 | 22 | Helical; Name=S4 of repeat III; Potential | ||||||
| Topological domain | 1401 – 1410 | 10 | Cytoplasmic Potential | ||||||
| Transmembrane | 1411 – 1434 | 24 | Helical; Name=S5 of repeat III; Potential | ||||||
| Topological domain | 1435 – 1511 | 77 | Extracellular Potential | ||||||
| Transmembrane | 1512 – 1537 | 26 | Helical; Name=S6 of repeat III; Potential | ||||||
| Topological domain | 1538 – 1610 | 73 | Cytoplasmic Potential | ||||||
| Transmembrane | 1611 – 1631 | 21 | Helical; Name=S1 of repeat IV; Potential | ||||||
| Topological domain | 1632 – 1645 | 14 | Extracellular Potential | ||||||
| Transmembrane | 1646 – 1667 | 22 | Helical; Name=S2 of repeat IV; Potential | ||||||
| Topological domain | 1668 – 1674 | 7 | Cytoplasmic Potential | ||||||
| Transmembrane | 1675 – 1693 | 19 | Helical; Name=S3 of repeat IV; Potential | ||||||
| Topological domain | 1694 – 1707 | 14 | Extracellular Potential | ||||||
| Transmembrane | 1708 – 1731 | 24 | Helical; Name=S4 of repeat IV; Potential | ||||||
| Topological domain | 1732 – 1745 | 14 | Cytoplasmic Potential | ||||||
| Transmembrane | 1746 – 1766 | 21 | Helical; Name=S5 of repeat IV; Potential | ||||||
| Topological domain | 1767 – 1826 | 60 | Extracellular Potential | ||||||
| Transmembrane | 1827 – 1854 | 28 | Helical; Name=S6 of repeat IV; Potential | ||||||
| Topological domain | 1855 – 2377 | 523 | Cytoplasmic Potential | ||||||
| Repeat | 68 – 398 | 331 | I | ||||||
| Repeat | 729 – 967 | 239 | II | ||||||
| Repeat | 1263 – 1540 | 278 | III | ||||||
| Repeat | 1596 – 1854 | 259 | IV | ||||||
| Compositional bias | 290 – 295 | 6 | Poly-Gly | ||||||
| Compositional bias | 496 – 506 | 11 | Poly-His | ||||||
Sites | |||||||||
| Site | 354 | 1 | Calcium ion selectivity and permeability By similarity | ||||||
| Site | 924 | 1 | Calcium ion selectivity and permeability By similarity | ||||||
| Site | 1465 | 1 | Calcium ion selectivity and permeability By similarity | ||||||
| Site | 1770 | 1 | Calcium ion selectivity and permeability By similarity | ||||||
Amino acid modifications | |||||||||
| Glycosylation | 173 | 1 | N-linked (GlcNAc...) Potential | ||||||
| Glycosylation | 246 | 1 | N-linked (GlcNAc...) Potential | ||||||
| Glycosylation | 306 | 1 | N-linked (GlcNAc...) Potential | ||||||
| Glycosylation | 310 | 1 | N-linked (GlcNAc...) Potential | ||||||
| Glycosylation | 322 | 1 | N-linked (GlcNAc...) Potential | ||||||
| Glycosylation | 1448 | 1 | N-linked (GlcNAc...) Potential | ||||||
| Glycosylation | 1451 | 1 | N-linked (GlcNAc...) Potential | ||||||
| Glycosylation | 1698 | 1 | N-linked (GlcNAc...) Potential | ||||||
Natural variations | |||||||||
| Alternative sequence | 971 – 993 | 23 | Missing in isoform 1, isoform 2, isoform 3, isoform 4, isoform 8, isoform 9 and isoform 10. | VSP_000940 | |||||
| Alternative sequence | 1569 – 1587 | 19 | NLMLD…SAASE → K in isoform 2 and isoform 13. | VSP_000944 | |||||
| Alternative sequence | 1569 – 1586 | 18 | NLMLD…ASAAS → SKEKQMA in isoform 1, isoform 4, isoform 6, isoform 7 and isoform 8. | VSP_000943 | |||||
| Alternative sequence | 1928 – 2020 | 93 | Missing in isoform 1, isoform 2, isoform 4, isoform 6, isoform 9, isoform 11 and isoform 13. | VSP_000946 | |||||
| Alternative sequence | 1928 – 1975 | 48 | Missing in isoform 10. | VSP_000945 | |||||
| Alternative sequence | 1976 – 2020 | 45 | Missing in isoform 7, isoform 8 and isoform 12. | VSP_000947 | |||||
| Alternative sequence | 2156 – 2234 | 79 | Missing in isoform 4. | VSP_000948 | |||||
Experimental info | |||||||||
| Sequence conflict | 1345 | 1 | S → I in AAD12731. Ref.7 | ||||||
Sequences
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References
| « Hide 'large scale' references | |
| [1] | "Structure and alternative splicing of the gene encoding alpha1G, a human brain T calcium channel alpha1 subunit." Mittman S., Guo J., Agnew W.S. Neurosci. Lett. 274:143-146(1999) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], ALTERNATIVE SPLICING (ISOFORMS 4 AND 5). Tissue: Brain. |
| [2] | "Molecular cloning and functional expression of ca(v)3.1c, a T-type calcium channel from human brain." Cribbs L.L., Gomora J.C., Daud A.N., Lee J.-H., Perez-Reyes E. FEBS Lett. 466:54-58(2000) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1). Tissue: Brain. |
| [3] | "Molecular and functional properties of the human alpha1G subunit that forms T-type calcium channels." Monteil A., Chemin J., Bourinet E., Mennessier G., Lory P., Nargeot J. J. Biol. Chem. 275:6090-6100(2000) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], ALTERNATIVE SPLICING (ISOFORMS 1-2 AND 6-13). Tissue: Brain. |
| [4] | "Characterization of cDNA clones selected by the GeneMark analysis from size-fractionated cDNA libraries from human brain." Hirosawa M., Nagase T., Ishikawa K., Kikuno R., Nomura N., Ohara O. DNA Res. 6:329-336(1999) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] OF 550-2377 (ISOFORM 13). Tissue: Brain. |
| [5] | "Construction of expression-ready cDNA clones for KIAA genes: manual curation of 330 KIAA cDNA clones." Nakajima D., Okazaki N., Yamakawa H., Kikuno R., Ohara O., Nagase T. DNA Res. 9:99-106(2002) [PubMed] [Europe PMC] [Abstract] Cited for: SEQUENCE REVISION. |
| [6] | "Inactivation of CACNA1G, a T-type calcium channel gene, by aberrant methylation of its 5' CpG island in human tumors." Toyota M., Ho C., Ohe-Toyota M., Baylin S.B., Issa J.-P.J. Cancer Res. 59:4535-4541(1999) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 3), GENE STRUCTURE. Tissue: Prostatic carcinoma. |
| [7] | "Molecular characterization of a neuronal low-voltage-activated T-type calcium channel." Perez-Reyes E., Cribbs L.L., Daud A., Lacerda A.E., Barclay J., Williamson M.P., Fox M., Rees M., Lee J.-H. Nature 391:896-900(1998) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 1126-1444; 1778-1927 AND 2021-2312. Tissue: Brain. |
| + | Additional computationally mapped references. |
Cross-references
Entry information
| Entry name | CAC1G_HUMAN | ||||||||
| Accession | Primary (citable) accession number: O43497 Secondary accession number(s): O43498 Q9Y5T3 | ||||||||
| Entry history |
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| Entry status | Reviewed (UniProtKB/Swiss-Prot) | ||||||||
| Annotation program | Chordata Protein Annotation Program | ||||||||
| Disclaimer | Any medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care. | ||||||||
Relevant documents
| Human chromosome 17 Human chromosome 17: entries, gene names and cross-references to MIM |
| MIM cross-references Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot |
| SIMILARITY comments Index of protein domains and families |

Clusters with
