PTX3 [SEP] found in taxon
sharing 82% identical and 92% conserved amino acids. The human PTX3 gene is organized into three exons coding for the leader peptide (which is cleaved from the mature protein), the amino-terminal domain and the pentraxin domain of the protein.
The transcribed PTX3 protein is 381 amino acids long, has a predicted molecular weight of 40,165 Da and consists of a carboxy-terminal 203 amino acid long pentraxin domain coupled with an amino-terminal 178 amino acid long domain unrelated to other known proteins. The PTX3 carboxy
on the cell surface, suggesting a role for PTX3 in the complement-mediated clearance of apoptotic cells. Moreover, in the presence of dying cells, PTX3 restricts the cross presentation of antigens derived from dying cells. These results suggest that PTX3 has a dual role: protection against pathogens and control of autoimmunity.