Canopy 3 Homolog (CNPY3)

PRAT4A is associated with the immature form of TLR4 and regulates its cell surface expression .The 278-amino acid PRAT4A protein has a 37-amino acid N-terminal signal sequence, a canonical N-glycosylation site, and 6 cys residues. It shares significant homology with mouse Prat4a and human PRAT4B. Northern blot analysis detected Prat4a expression in all mouse tissues examined.

Knockdown of PRAT4A diminished TLR4/MD2 expression, as well as lipopolysaccharide responsiveness. Human PRAT4A bound hypoglycosylated mouse Tlr4 with or without Md2, but it did not bind mature Tlr4/Md2, in human and mouse cells. PRAT4A has a role in TLR4 maturation and glycosylation.