Adenomatosis polyposis coli down-regulated 1 protein (APCDD1)

Adenomatosis polyposis coli down-regulated 1 protein (APCDD1) is a conserved single-pass transmembrane glycoprotein with a large extracellular domain comprising two β-barrel structures, one of which contains a hydrophobic pocket that binds lipids. It serves as a negative regulator of WNT signaling by directly binding to lipid-modified WNT ligands, thereby titrating their activity at the cell surface. APCDD1 plays essential roles in hair follicle development, central nervous system and retinal vascular patterning, glial differentiation, adipocyte maturation, and epithelial morphogenesis. Genetic variants are associated with hereditary hair loss (hypotrichosis simplex), and altered expression has been implicated in colorectal cancer, breast cancer, multiple sclerosis, and developmental CNS disorders. APCDD1 is being explored as a cell-state marker and as an epigenetic biomarker for prenatal diagnosis. Therapeutic modulation of APCDD1 is theoretically possible but must consider its multifaceted role in development and neurovascular integrity.

Other names

APCDD1Protein APCDD1DRAPC1FP7019B7323Adenomatosis polyposis coli down-regulated 1 proteinhypoptrichosis simplexHHSHTSHYPT1

For experimental modulation, the mechanism is inhibition or titration of extracellular WNT ligands to suppress downstream WNT/β-catenin signaling