[Structure and function of the scavenger receptor]

Abstract

The macrophage scavenger receptors are consisted of six domains: cytoplasmic, membrane-spanning, spacer, alpha-helical coiled-coil, collagen-like and a type-specific C-terminal. The collagen-like domain is revealed to have important role for ligand binding. The receptor gene is located on human chromosome 8. The human scavenger gene spans approximately 80 kb and is composed of 11 exons. Two types of scavenger receptor mRNA were shown to result from alternative splicing of exon 9 for type II or 10 and 11 for type I to the common exon 1-8. The scavenger receptor proteins were detected in macrophages of various organs and tissues such as Kupffer cells, alveolar macrophages, macrophages in the spleen and lymph nodes and perivascular macrophages in the brain. In the atheromatous plaques, scavenger receptors may participate progression of foam cells. Elimination and detoxication of endotoxin by macrophage scavenger receptor may suggest the defending function against a wide variety of pathogenic agents.