Basic Salivary Proline Rich Protein 4 (PRB4)

Basic salivary proline-rich protein 4 is a proline-rich salivary protein. This gene and five other genes that also encode salivary proline-rich proteins (PRPs), as well as a gene encoding a lacrimal gland PRP, form a PRP gene cluster in the chromosomal 12p13 region.it was typed on immunoblots after transfer from SDS gels to nitrocellulose. The Po+ allele had a frequency of 0.75 in whites and 0.77 in blacks. Po is probably linked to the salivary protein complex (SPC); Po versus CON2 showed a maximum lod score of 2.35 at theta = 0.0. The Po protein and a glycoprotein (II-1) are indeed encoded in the PRB4 gene. The authors noted that concanavalin-A binding proteins are of special biologic interest, since they, like other proline-rich proteins of the saliva, might bind to specific oral bacteria and modulate intraoral disease susceptibility.