Croquemort, A Novel Drosophila Hemocyte/Macrophage Receptor that Recognizes Apoptotic Cells

Abstract

Programmed cell death is first observed at stage 11 of embryogenesis in Drosophila. The systematic removal of apoptotic cells is mediated by cells that are derived from the procephalic mesoderm and differentiate into macrophages. We describe a macrophage receptor for apoptotic cells. This receptor, croquemort (catcher of death), is a member of the CD36 superfamily. Croquemort-mediated phagocytosis represents the concept that phagocytosis evolved primarily as a cellular process for the removal of effete cells. Our findings support the idea that the primordial function of macrophages may have been in tissue modeling and that their adapted role is in host defense.

A novel hemocyte‐specific membrane protein of Sarcophaga (flesh fly)

“…Only two hemocyte-specific membrane proteins have been characterized in insects: one is dSR-CI, a Drosophila scavenger receptor [27], and the other is Croquemort, a possible Drosophila homologue of human CD36 [28,29]. However, these proteins are not specific to the prepupal stage.…”

CD36: Implications in cardiovascular disease

“…CD36 is classified as a class B scavenger receptor (Platt, & Gordon, 1998,Krieger, 1997, and is part of a gene family that includes lysosomal integral membrane protein II (LIMP-II), which plays a role in nerve myelinization (Gamp, et al, 2003), CD36 and LIMP-II analogous-I protein (CLA-1) (known as scavenger receptor BI (SR-BI) in mice), which mediates the selective uptake of cholesterol esters from high density lipoprotein (HDL) (Acton, Rigotti, Landschulz, Xu, Hobbs, & Krieger, 1996), and Croquemorte, a drosophila protein, that phagocytoses apoptotic cells and senescent erythrocytes (Franc, Dimarcq, Lagueux, Hoffmann, & Ezekowitz, 1996,Franc, Heitzler, Ezekowitz, & White, 1999. Scavenger receptors are found in both primitive and immunologically advanced organisms and their continued evolutionary conservation suggest their important role at the forefront of the initial organism response to pathogens and in normal homeostasis (Krieger, 1997,Gordon, 2002.…”

Molecular mechanisms of cell death and phagocytosis in Drosophila

“…88 Croquemort (Crq), a Drosophila member of the CD36 family of receptors, is one such receptor. 89 Crq is expressed exclusively on macrophages during embryogenesis. It is most prominently expressed at the membrane surface of subcellular vesicles that contain apoptotic corpses.…”