Selenoprotein I

SELENOI
Identifiers
Aliases	SELENOI, SELI, SEPI, EPT1, ethanolaminephosphotransferase 1, selenoprotein I, SPG81
External IDs	OMIM: 607915; MGI: 107898; GeneCards: SELENOI
Enzyme activity
Gene location (Human)
Chr.	Chromosome 2 (human)
End	26,395,885 bp
Gene location (Mouse)
Chr.	Chromosome 5 (mouse)
End	30,477,425 bp
RNA expression pattern
	Top expressed in
	mucosa of ileum; ; jejunal mucosa; ; tibialis anterior muscle; ; secondary oocyte; ; middle temporal gyrus; ; skin of arm; ; cerebellar vermis; ; islet of Langerhans; ; Achilles tendon; ; buccal mucosa cell;
	Top expressed in
	superior cervical ganglion; ; epithelium of small intestine; ; spermatid; ; ileum; ; jejunum; ; spermatocyte; ; tail of embryo; ; cumulus cell; ; epithelium of stomach; ; hand;
	More reference expression data
	n/a
Gene ontology
Molecular function	transferase activity; phosphotransferase activity, for other substituted phosphate groups; metal ion binding; ethanolaminephosphotransferase activity;
Cellular component	integral component of membrane; endoplasmic reticulum membrane; membrane; Golgi apparatus;
Biological process	phosphatidylethanolamine biosynthetic process; lipid metabolism; phospholipid biosynthetic process;
	Sources:Amigo / QuickGO
Orthologs
Databases	NCBI: entry; OMA: entry
	85465
	28042
	ENSG00000138018
	ENSMUSG00000075703
	Q9C0D9
	Q80TA1
	NM_033505
	NM_027652
	NP_277040
	NP_081928
	Wikidata
View/Edit Human	View/Edit Mouse

Selenoprotein I, also called ethanolaminephosphotransferase 1, is an enzyme that in humans is encoded by the SELENOI gene (previously EPT1). As an ethanolaminephosphotransferase, Selenoprotein I functions to transfer a phosphoethanolamine (PE) from a CDP-ethanolamine donor to a lipid acceptor. This enzyme is important for the synthesis of several types of PE, which are important components of cell membranes, and is particularly important for myelination and nervous system development.

Medical Significance

Pathogenic mutations in SELENOI are associated with progressive dysfunction of the nervous system and muscle control. This condition, called spastic paraplegia-81 (SPG81), is inherited in an autosomal recessive manner.

References

1 2 3 GRCh38: Ensembl release 89: ENSG00000138018 – Ensembl, May 2017
1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000075703 – Ensembl, May 2017
↑ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
↑ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
1 2 3 "Ethanolaminephosphotransferase 1". uniprot.org. UniProt consortium. Retrieved 2026-10-13.
1 2 Li F, Shi Z, Cheng M, Zhou Z, Chu M, Sun L, Zhou JC (2023-11-01). "Biology and roles in diseases of selenoprotein I characterized by ethanolamine phosphotransferase activity and antioxidant potential". The Journal of Nutrition. 153 (11): 3164–72. doi:10.1016/j.tjnut.2023.03.023. PMID 36963501.
1 2 Kniffin CL, Vernon HJ (2023-08-18). "SPASTIC PARAPLEGIA 81, AUTOSOMAL RECESSIVE; SPG81". Online Mendelian Inheritance in Man. Johns Hopkins university. Retrieved 2026-10-13.

This article on a gene on human chromosome 2 is a stub. You can help Wikipedia by adding missing information.

[refGRCh38Ensembl-1] 1 2 3 GRCh38: Ensembl release 89: ENSG00000138018 – Ensembl, May 2017

[refGRCm38Ensembl-2] 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000075703 – Ensembl, May 2017

[3] "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.

[4] "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.

[uniprot-5] 1 2 3 "Ethanolaminephosphotransferase 1". uniprot.org. UniProt consortium. Retrieved 2026-10-13.

[Li2023-6] 1 2 Li F, Shi Z, Cheng M, Zhou Z, Chu M, Sun L, Zhou JC (2023-11-01). "Biology and roles in diseases of selenoprotein I characterized by ethanolamine phosphotransferase activity and antioxidant potential". The Journal of Nutrition. 153 (11): 3164–72. doi:10.1016/j.tjnut.2023.03.023. PMID 36963501.

[omim-7] 1 2 Kniffin CL, Vernon HJ (2023-08-18). "SPASTIC PARAPLEGIA 81, AUTOSOMAL RECESSIVE; SPG81". Online Mendelian Inheritance in Man. Johns Hopkins university. Retrieved 2026-10-13.