basic salivary proline-rich protein 2; con1 glycoprotein; contains: basic proline-rich peptide IB-1; basic proline-rich peptide P-E; IB-9 basic proline-rich peptide IB-7; basic proline-rich peptide IB-8c; basic peptide P-F; basic proline-rich peptide IB-4 (PRB2)

Function: - proteolytically cleaved at the tripeptide Xaa-Pro-Gln, where Xaa in the P(3) position is mostly Lys - the endoprotease may be of microbial origin - pyroglutamate formation occurs on terminal Gln of cleaved peptides - pyroglutamate formation found on at least Gln-398 & Gln-400 Structure: - N-glycosylated & O-glycosylated Compartment: secreted (putative) Pathology: - in head & neck cancer patients, O-glycosylated with glucosylgalactosyl carbohydrate moiety - this modification would require prior hydroxylation on Lys Polymorphism: - the number of repeats is polymorphic & varies among different alleles Notes: peptides IB-9 & P-E are the same peptide

General

phosphoprotein salivary proline-rich protein

Properties

SIZE: entity length = 416 aa MW = 41 kD COMPARTMENT: saliva MOTIF: signal sequence {1-16} Ser phosphorylation site {S24} Ser phosphorylation site {S52} domain {53-360} MOTIF: consensus repeat {53-72} consensus repeat {74-93} consensus repeat {94-113} consensus repeat {114-133} consensus repeat {135-154} consensus repeat {155-174} N-glycosylation site {N168} consensus repeat {176-195} consensus repeat {197-216} consensus repeat {217-236} N-glycosylation site {N230} Ser glycosylation site {S232} consensus repeat {238-257} consensus repeat {259-278} N-glycosylation site {N272} consensus repeat {279-298} consensus repeat {300-319} consensus repeat {321-340} consensus repeat {341-360}

Database Correlations

OMIM 168810 UniProt P02812

References

UniProt :accession P02812