Cytokine which is involved in epithelial-mesenchymal signaling during morphogenesis of ectodermal organs. Functions as a ligand activating the DEATH-domain containing receptors EDAR and EDA2R (PubMed:8696334, PubMed:11039935, PubMed:27144394, PubMed:34582123). May also play a role in cell adhesion (By similarity). Binds only to the receptor EDAR, while isoform 3 binds exclusively to the receptor EDA2R. Binds only to the receptor EDA2R. Homotrimer. The homotrimers may then dimerize and form higher-order oligomers. Additional isoforms seem to exist. Not abundant; expressed in specific cell types of ectodermal (but not mesodermal) origin of keratinocytes, hair follicles, sweat glands. Also in adult heart, liver, muscle, pancreas, prostate, fetal liver, uterus, small intestine and umbilical chord. N-glycosylated. Processing by furin produces a secreted form. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Belongs to the tumor necrosis factor family. Intron retention.