solute carrier family 22 member 5
Last updated 27 Nov 2023
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The SLC22A5 gene provides instructions for making a protein called OCTN2 that is found in the heart, liver, muscles, kidneys, and other tissues. This protein is positioned within the cell membrane, where it transports a substance known as carnitine into the cell. Carnitine is mainly obtained from food and is needed to bring certain types of fats (fatty acids) into mitochondria, which are the energy-producing centers within cells. Fatty acids are a major source of energy for the heart and muscles. During periods without food (fasting), fatty acids become the most important energy source for the heart and other muscles.
Normal function
The SLC22A5 gene provides instructions for making a protein called OCTN2 that is found in the heart, liver, muscles, kidneys, and other tissues. This protein is positioned within the cell membrane, where it transports a substance known as carnitine into the cell. Carnitine is mainly obtained from food and is needed to bring certain types of fats (fatty acids) into mitochondria, which are the energy-producing centers within cells. Fatty acids are a major source of energy for the heart and muscles. During periods without food (fasting), fatty acids become the most important energy source for the heart and other muscles.
Conditions referring to this gene or chromosome
Other names
CDSP
high-affinity sodium dependent carnitine cotransporter
novel organic cation transporter 2
OCTN2
organic cation transporter 5
organic cation/carnitine transporter 2
S22A5_HUMAN
SCD
solute carrier family 22 (organic cation transporter), member 5
solute carrier family 22 (organic cation/carnitine transporter), member 5
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Further reading and references
- solute carrier family 22 member 5; MedlinePlus, National Library of Medicine.
- Amat di San Filippo C, Longo N. Tyrosine residues affecting sodium stimulation of carnitine transport in the OCTN2 carnitine/organic cation transporter. J Biol Chem. 2004 Feb 20;279(8):7247-53. doi: 10.1074/jbc.M309171200. Epub 2003 Dec 9.
- Amat di San Filippo C, Wang Y, Longo N. Functional domains in the carnitine transporter OCTN2, defective in primary carnitine deficiency. J Biol Chem. 2003 Nov 28;278(48):47776-84. doi: 10.1074/jbc.M307911200. Epub 2003 Sep 23.
- Ferdinandusse S, Te Brinke H, Ruiter JPN, Haasjes J, Oostheim W, van Lenthe H, IJlst L, Ebberink MS, Wanders RJA, Vaz FM, Waterham HR. A mutation creating an upstream translation initiation codon in SLC22A5 5'UTR is a frequent cause of primary carnitine deficiency. Hum Mutat. 2019 Oct;40(10):1899-1904. doi: 10.1002/humu.23839. Epub 2019 Jul 3.
- Inano A, Sai Y, Kato Y, Tamai I, Ishiguro M, Tsuji A. Functional regions of organic cation/carnitine transporter OCTN2 (SLC22A5): roles in carnitine recognition. Drug Metab Pharmacokinet. 2004 Jun;19(3):180-9. doi: 10.2133/dmpk.19.180.
- Koepsell H, Endou H. The SLC22 drug transporter family. Pflugers Arch. 2004 Feb;447(5):666-76. doi: 10.1007/s00424-003-1089-9. Epub 2003 Jul 19.
- Lahjouji K, Mitchell GA, Qureshi IA. Carnitine transport by organic cation transporters and systemic carnitine deficiency. Mol Genet Metab. 2001 Aug;73(4):287-97. doi: 10.1006/mgme.2001.3207.
- Li FY, El-Hattab AW, Bawle EV, Boles RG, Schmitt ES, Scaglia F, Wong LJ. Molecular spectrum of SLC22A5 (OCTN2) gene mutations detected in 143 subjects evaluated for systemic carnitine deficiency. Hum Mutat. 2010 Aug;31(8):E1632-51. doi: 10.1002/humu.21311.
- Nezu J, Tamai I, Oku A, Ohashi R, Yabuuchi H, Hashimoto N, Nikaido H, Sai Y, Koizumi A, Shoji Y, Takada G, Matsuishi T, Yoshino M, Kato H, Ohura T, Tsujimoto G, Hayakawa J, Shimane M, Tsuji A. Primary systemic carnitine deficiency is caused by mutations in a gene encoding sodium ion-dependent carnitine transporter. Nat Genet. 1999 Jan;21(1):91-4. doi: 10.1038/5030.
- Tein I. Carnitine transport: pathophysiology and metabolism of known molecular defects. J Inherit Metab Dis. 2003;26(2-3):147-69. doi: 10.1023/a:1024481016187.
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