PRB4 explained

Basic salivary proline-rich protein 4 is a protein that in humans is encoded by the PRB4 gene.^[1]

The protein encoded by this gene 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.

PRB4 is post-translationally cleaved into three different mature peptides:

• Protein N1
• Glycosylated protein A
• Peptide P-D (also known as proline-rich peptide IB-5)

Further reading

• Book: Azen EA, Maeda N . Advances in Human Genetics 1 . Molecular Genetics of Human Salivary Proteins and Their Polymorphisms . 17 . 141–199 . 1988 . 3055850 . 10.1007/978-1-4613-0987-1_5. 978-1-4612-8279-2 .
• Bennick A . Salivary proline-rich proteins . Mol. Cell. Biochem. . 45 . 2 . 83–99 . 1982 . 6810092 . 10.1007/BF00223503 . 31373141 .
• Lyons KM, Stein JH, Smithies O . Length Polymorphisms in Human Proline-Rich Protein Genes Generated by Intragenic Unequal Crossing over . Genetics . 120 . 1 . 267–78 . 1989 . 10.1093/genetics/120.1.267 . 2851479 . 1203497 .
• Maeda N, Kim HS, Azen EA, Smithies O . Differential RNA splicing and post-translational cleavages in the human salivary proline-rich protein gene system . J. Biol. Chem. . 260 . 20 . 11123–30 . 1985 . 10.1016/S0021-9258(17)39156-1 . 2993301 . free .
• Lyons KM, Azen EA, Goodman PA, Smithies O . Many Protein Products from a Few Loci: Assignment of Human Salivary Proline-Rich Proteins to Specific Loci . Genetics . 120 . 1 . 255–65 . 1989 . 10.1093/genetics/120.1.255 . 3220251 . 1203496 .
• Warner TF, Azen EA . Proline-rich proteins are present in serous cells of submucosal glands in the respiratory tract . Am. Rev. Respir. Dis. . 130 . 1 . 115–8 . 1984 . 6377992 . 10.1164/arrd.1984.130.1.115. 31 January 2024 .
• Saitoh E, Isemura S, Sanada K . Complete amino acid sequence of a basic proline-rich peptide, P-D, from human parotid saliva . J. Biochem. . 93 . 2 . 495–502 . 1983 . 6841349 . 10.1093/jb/93.3.883 .
• Kauffman DL, Keller PJ, Bennick A, Blum M . Alignment of amino acid and DNA sequences of human proline-rich proteins . Crit. Rev. Oral Biol. Med. . 4 . 3–4 . 287–92 . 1993 . 8373986 . 10.1177/10454411930040030501. free .
• Kim HS, Lyons KM, Saitoh E, etal . The structure and evolution of the human salivary proline-rich protein gene family . Mamm. Genome . 4 . 1 . 3–14 . 1993 . 8422499 . 10.1007/BF00364656 . 24058984 .
• Azen EA, Amberger E, Fisher S, etal . PRB1, PRB2, and PRB4 coded polymorphisms among human salivary concanavalin-A binding, II-1, and Po proline-rich proteins . Am. J. Hum. Genet. . 58 . 1 . 143–53 . 1996 . 8554050 . 1914931 .
• Castle AM, Castle JD . Enhanced Glycosylation and Sulfation of Secretory Proteoglycans Is Coupled to the Expression of a Basic Secretory Protein . Mol. Biol. Cell . 9 . 3 . 575–83 . 1998 . 9487127 . 10.1091/mbc.9.3.575. 25286 .
• Chan M, Bennick A . Proteolytic processing of a human salivary proline-rich protein precursor by proprotein convertases . Eur. J. Biochem. . 268 . 12 . 3423–31 . 2001 . 11422372 . 10.1046/j.1432-1327.2001.02241.x . free .
• Strausberg RL, Feingold EA, Grouse LH, etal . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . 2002PNAS...9916899M . free .
• Vallat JM, Magy L, Lagrange E, etal . Diagnostic value of ultrastructural nerve examination in Charcot-Marie-Tooth disease: two CMT 1B cases with pseudo-recessive inheritance . Acta Neuropathol. . 113 . 4 . 443–9 . 2007 . 17294201 . 10.1007/s00401-007-0196-7 . 42561185 .

Notes and References

1. Web site: Entrez Gene: PRB4 proline-rich protein BstNI subfamily 4.