THE EOSINOPHIL RIBONUCLEASES

The eosinophil ribonucleases, eosinophil-derived neurotoxin (EDN/RNase 2) and eosinophil cationic protein (ECP/RNase 3) are two closely rela ted proteins with intriguing functional and evolutionary properties. W hile both EDN and ECP maintain the structural and catalytic residues t ypical of the RNase A superfamily, the role of ribonuclease activity i n the physiologic function of these proteins remains unclear. The bioc hemistry and physiology of EDN, ECP and the recently discovered ribonu clease k6 (RNase 6) will be reviewed in this chapter.