Neuronal Pentraxin R/NPTXR: ProductsNPTXR (Neuronal Pentraxin Receptor; also NPR) is a 65 kDa, type II transmembrane glycoprotein that binds Neuronal Pentraxins 1 and 2. It is expressed on cerebellar Purkinje and granule cells, and hippocampal neurons of the CA1, CA3 and dentate gyrus regions. Human Neuronal Pentraxin Receptor is 499 amino acids (aa) in length. It contains a two aa cytoplasmic tail, a 21 aa transmembrane segment, and a 476 aa extracellular region with one Pentraxin domain (aa 295 - 499). One alternate start site exists at Met12, and a 55 kDa soluble form of NPTXR (possibly beginning at Gln56) may be generated by proteolytic cleavage. Over aa 24 - 499, human NPTXR is 87% aa identical to mouse NPTXR.