presenilin 1
Last updated 19 Nov 2025
Meets Patient’s editorial guidelines
- DownloadDownload
- Share
- Language
- Discussion
- Audio Version
- Add to preferred sources on Google
The PSEN1 gene provides instructions for making a protein called presenilin 1. This protein is one part (subunit) of a complex called gamma- (γ-) secretase. Presenilin 1 carries out the major function of the complex, which is to cut apart (cleave) other proteins into smaller pieces called peptides. This process is called proteolysis, and presenilin 1 is described as the proteolytic subunit of γ-secretase.
Normal function
The PSEN1 gene provides instructions for making a protein called presenilin 1. This protein is one part (subunit) of a complex called gamma- (γ-) secretase. Presenilin 1 carries out the major function of the complex, which is to cut apart (cleave) other proteins into smaller pieces called peptides. This process is called proteolysis, and presenilin 1 is described as the proteolytic subunit of γ-secretase.
The γ-secretase complex is located in the membrane that surrounds cells, where it cleaves many different proteins that span the cell membrane (transmembrane proteins). This cleavage is an important step in several chemical signaling pathways that transmit signals from outside the cell into the nucleus. One of these pathways, known as Notch signaling, is essential for the normal growth and maturation (differentiation) of hair follicle cells and other types of skin cells. Notch signaling is also involved in normal immune system function.
The γ-secretase complex may be best known for its role in processing amyloid precursor protein (APP), which is made in the brain and other tissues. γ-secretase cuts APP into smaller peptides, including soluble amyloid precursor protein (sAPP) and several versions of amyloid-beta (β) peptide. Evidence suggests that sAPP has growth-promoting properties and may play a role in the formation of nerve cells (neurons) in the brain both before and after birth. Other functions of sAPP and amyloid-β peptide are under investigation.
Conditions referring to this gene or chromosome
Other names
AD3
FAD
presenilin 1 (Alzheimer disease 3)
presenilin 1 protein
PS1
PSN1_HUMAN
PSNL1 gene product
S182 protein
Related patient information and medicines
Patient information leaflet
Travelling to remote locations
Personal first aid kit for a remote trip The following lists a comprehensive first aid kit for two people travelling together to a remote environment. Self-treatment is a last resort as it is very difficult for anyone to make trea... Reference book Pocket First Aid and Wilderness Medicine: Drs Jim Duff and Peter Gormly (2010). This is an excellent.
Patient information leaflet
Down's syndrome screening
There are two different types of tests that can be done to look for Down's syndrome during pregnancy - a screening test and a diagnostic test. Alternatively, you may choose to have a second blood screening test called non-invasive prenatal screening (NIPT). This gives a more accurate assessment of the chance and carries no risk to your baby, but.
Patient information leaflet
Giant Cell Arteritis
Steroid tablets A steroid medicine such as prednisolone is the usual main treatment. People being prescribed long-term steroids will usually also be prescribed calcium and medication to protect the stomach ( proton pump inhibitors ). In the UK, the National Institute for Health and Care Excellence (NICE) guidance is currently that this should only.
Patient information leaflet
Altitude sickness
Altitude sickness can affect people who climb or travel (ascend) to more than 2500 metres (8,000 feet) altitude, particularly if they ascend too quickly. For most people, it causes mild symptoms that improve with rest and with time spent getting used to altitude. Medicines are sometimes prescribed to hel... The most common is a medicine called.
Patient information leaflet
Type 2 diabetes treatment
If you have CKD, you should also be taking an ACE inhibitor or ARB - drugs developed to treat high blood pressure , but which can. The current recommendations for SGLT-2 inhibitors in type 2 diabetes and CKD are: Your doctor may recommend an SGLT-2 inhibitor even if you do not have CKD, to protect you from developing it. See the leaflet that comes.
Patient information leaflet
Seborrhoeic dermatitis
Seborrhoeic dermatitis causes bad dandruff and sometimes a rash, commonly on the face and upper body. An anti-yeast (antifungal) shampoo and/or an antifungal cream will usually clear the dandruff and rash. In most cases, no investigatio... Seborrhoeic dermatitis treatment Commonly used treatments include the following: An anti-yeast (antifungal).
Further reading and references
- presenilin 1; MedlinePlus, National Library of Medicine.
- Cordy JM, Hooper NM, Turner AJ. The involvement of lipid rafts in Alzheimer's disease. Mol Membr Biol. 2006 Jan-Feb;23(1):111-22. doi: 10.1080/09687860500496417.
- Das HK. Transcriptional regulation of the presenilin-1 gene: implication in Alzheimer's disease. Front Biosci. 2008 Jan 1;13:822-32. doi: 10.2741/2723.
- Larner AJ, Doran M. Clinical phenotypic heterogeneity of Alzheimer's disease associated with mutations of the presenilin-1 gene. J Neurol. 2006 Feb;253(2):139-58. doi: 10.1007/s00415-005-0019-5. Epub 2005 Nov 4.
- Melnik BC, Plewig G. Impaired Notch signalling: the unifying mechanism explaining the pathogenesis of hidradenitis suppurativa (acne inversa). Br J Dermatol. 2013 Apr;168(4):876-8. doi: 10.1111/bjd.12068. Epub 2013 Jan 31. No abstract available.
- Pink AE, Simpson MA, Desai N, Dafou D, Hills A, Mortimer P, Smith CH, Trembath RC, Barker JNW. Mutations in the gamma-secretase genes NCSTN, PSENEN, and PSEN1 underlie rare forms of hidradenitis suppurativa (acne inversa). J Invest Dermatol. 2012 Oct;132(10):2459-2461. doi: 10.1038/jid.2012.162. Epub 2012 May 24. No abstract available.
- Pink AE, Simpson MA, Desai N, Trembath RC, Barker JNW. gamma-Secretase mutations in hidradenitis suppurativa: new insights into disease pathogenesis. J Invest Dermatol. 2013 Mar;133(3):601-607. doi: 10.1038/jid.2012.372. Epub 2012 Oct 25.
- Tanzi RE. The genetics of Alzheimer disease. Cold Spring Harb Perspect Med. 2012 Oct 1;2(10):a006296. doi: 10.1101/cshperspect.a006296.
- Thinakaran G, Parent AT. Identification of the role of presenilins beyond Alzheimer's disease. Pharmacol Res. 2004 Oct;50(4):411-8. doi: 10.1016/j.phrs.2003.12.026.
- Wang B, Yang W, Wen W, Sun J, Su B, Liu B, Ma D, Lv D, Wen Y, Qu T, Chen M, Sun M, Shen Y, Zhang X. Gamma-secretase gene mutations in familial acne inversa. Science. 2010 Nov 19;330(6007):1065. doi: 10.1126/science.1196284. Epub 2010 Oct 7.
Join the conversation
Share your thoughts or experiences with others in our patient communities.
Ask, share, connect.
Browse discussions, ask questions, and share experiences across hundreds of health topics.
Sign up to the Patient newsletter
Your weekly dose of clear, trustworthy health advice - written to help you feel informed, confident and in control.
By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.