Involvement in disease
Defects is Scd1 are the cause of asebia (ab) (PubMed:17738154, PubMed:10545940, PubMed:10854228, PubMed:10899171, PubMed:15278437). The trait is due to spontaneous autosomal recessive mutations that give rise to deletions or point mutations in Scd1. The ab trait has complete penetrance (PubMed:17738154). Ab mice are characterized by reduced body weight, extreme sebaceous gland hypoplasia leading to nearly complete absence of sebaceous glands, and thickened, scaly skin with hyperkeratosis and alopecia (PubMed:17738154, PubMed:10854228, PubMed:15278437). The hair follicles are abnormally long and extend at a sharp angle into the subcutis, probably due to abnormal persistence of inner root sheath. Frequently the hair shaft ruptures through the base of the hair follicle, giving rise to inflammation that results in scarring alopecia (PubMed:10854228, PubMed:15278437). Besides, ab mice display increased transepithelial water loss (PubMed:10854228). Ab mice present a narrow eye fissure and their eyes are nearly closed (PubMed:10854228, PubMed:15278437). Older mice develop blindness (PubMed:17738154). Scd1 activity is almost absent in liver, and is not compensated by expression of another family member (PubMed:10899171). Liver levels of total cholesterol esters are decreased by 87%, while plasma cholesterol levels are increased by 35% (PubMed:10899171). Likewise, skin sterol esters and diol diesters are strongly reduced (PubMed:10854228). Liver triglyceride levels are decreased by 62%, while plasma triglyceride levels are decreased by 67% (PubMed:10899171). The fatty acid composition of liver triglycerides is altered, with a decrease of about 85% in palmitoleate (C16:1) and oleate (C18:1) levels (PubMed:10899171). These defects cannot be compensated by a diet enriched in unsaturated fatty acids (PubMed:10899171, PubMed:11441127).
Tissue Specificity
Detected in liver (at protein level). Detected in skin and liver. Detected in sebaceous gland, but not in hair follicle. Detected in white and brown adipose tissue, eyelid, Harderian gland, and at lower levels in Meibomian gland, eyeball and adrenal gland