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PRB4 proline rich protein BstNI subfamily 4 [ Homo sapiens (human) ]

Gene ID: 5545, updated on 9-Jun-2025
Official Symbol
PRB4provided by HGNC
Official Full Name
proline rich protein BstNI subfamily 4provided by HGNC
Primary source
HGNC:HGNC:9340
See related
Ensembl:ENSG00000230657 MIM:180990; AllianceGenome:HGNC:9340
Gene type
protein coding
RefSeq status
REVIEWED
Organism
Homo sapiens
Lineage
Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
Also known as
Po
Summary
This gene encodes a member of the heterogeneous family of basic, proline-rich, human salivary glycoproteins. The encoded preproprotein undergoes proteolytic processing to generate one or more mature peptides before secretion from the parotid glands. Multiple alleles of this gene exhibiting variations in the length of the tandem repeats have been identified. The reference genome encodes the "Small" allele. This gene is located in a cluster of closely related salivary proline-rich proteins on chromosome 12. Alternative splicing results in multiple transcript variants encoding different isoforms that may undergo similar proteolytic processing. [provided by RefSeq, Nov 2015]
Expression
Restricted expression toward salivary gland (RPKM 1203.4) See more
Orthologs
all
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See PRB4 in Genome Data Viewer
Location:
12p13.2
Exon count:
4
Annotation release Status Assembly Chr Location
RS_2024_08 current GRCh38.p14 (GCF_000001405.40) 12 NC_000012.12 (11307077..11310436, complement)
RS_2024_08 current T2T-CHM13v2.0 (GCF_009914755.1) 12 NC_060936.1 (11176189..11179610, complement)
RS_2024_09 previous assembly GRCh37.p13 (GCF_000001405.25) 12 NC_000012.11 (11460011..11463370, complement)

Chromosome 12 - NC_000012.12Genomic Context describing neighboring genes Neighboring gene uncharacterized LOC107987435 Neighboring gene taste 2 receptor member 7 pseudogene Neighboring gene proline rich protein BstNI subfamily 3 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr12:11443165-11443666 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr12:11443667-11444166 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr12:11450808-11451403 Neighboring gene P300/CBP strongly-dependent group 1 enhancer GRCh37_chr12:11512579-11513778 Neighboring gene proline rich protein BstNI subfamily 1 Neighboring gene proline rich protein BstNI subfamily 2

Go to nucleotide: Graphics FASTA GenBank

  • Project title: Tissue-specific circular RNA induction during human fetal development
  • Description: 35 human fetal samples from 6 tissues (3 - 7 replicates per tissue) collected between 10 and 20 weeks gestational time were sequenced using Illumina TruSeq Stranded Total RNA
  • BioProject: PRJNA270632
  • Publication: PMID 26076956
  • Analysis date: Mon Apr 2 22:54:59 2018

Related articles in PubMed

  1. Top-down platform for deciphering the human salivary proteome. Castagnola M, et al. J Matern Fetal Neonatal Med, 2012 Oct. PMID 23025766
  2. Many protein products from a few loci: assignment of human salivary proline-rich proteins to specific loci. Lyons KM, et al. Genetics, 1988 Sep. PMID 3220251, Free PMC Article
  3. Diagnostic value of ultrastructural nerve examination in Charcot-Marie-Tooth disease: two CMT 1B cases with pseudo-recessive inheritance. Vallat JM, et al. Acta Neuropathol, 2007 Apr. PMID 17294201
  4. Characterization of the human salivary basic proline-rich protein complex by a proteomic approach. Messana I, et al. J Proteome Res, 2004 Jul-Aug. PMID 15359733
  5. Proline-rich proteins are present in serous cells of submucosal glands in the respiratory tract. Warner TF, et al. Am Rev Respir Dis, 1984 Jul. PMID 6377992

See all (22) citations in PubMed

GeneRIFs: Gene References Into Functions

What's a GeneRIF?
  1. Two heterozygous mutations of po gene were identified: S63F and N131Y in Charcot-Marie-Tooth disease.
    Title: Diagnostic value of ultrastructural nerve examination in Charcot-Marie-Tooth disease: two CMT 1B cases with pseudo-recessive inheritance.
Submit: New GeneRIF Correction

Find tests for this gene in the NIH Genetic Testing Registry (GTR)

Review eQTL and phenotype association data in this region using PheGenI

See variants in ClinVar

See studies and variants in dbVar

See Variation Viewer (GRCh37.p13)

See Variation Viewer (GRCh38)

Products Interactant Other Gene Complex Source Pubs Description

Markers

Homology

Gene Ontology Provided by GOA

Component Evidence Code Pubs
located_in extracellular region IEA
Inferred from Electronic Annotation
more info
  
located_in extracellular region NAS
Non-traceable Author Statement
more info
 PubMed 
Preferred Names
basic salivary proline-rich protein 4
Names
BstNI type basic salivary proline-rich protein 4
parotid o protein
salivary proline-rich protein II-1
salivary proline-rich protein Po

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RefSeqs maintained independently of Annotated Genomes

These reference sequences exist independently of genome builds. Explain

These reference sequences are curated independently of the genome annotation cycle, so their versions may not match the RefSeq versions in the current genome build. Identify version mismatches by comparing the version of the RefSeq in this section to the one reported in Genomic regions, transcripts, and products above.

mRNA and Protein(s)

  1. NM_001261399.3 → NP_001248328.1  basic salivary proline-rich protein 4 isoform 2 preproprotein

    Status: REVIEWED

    Description
    Transcript Variant: This variant (2) lacks an alternate in-frame segment, compared to variant 1. The resulting isoform (2) has the same N- and C-termini but is shorter, compared to isoform 1. This isoform (2) may undergo proteolytic processing similar to isoform 1.
    Source sequence(s)
    AC010176
    Consensus CDS
    CCDS58208.1
    UniProtKB/TrEMBL
    A2VCL9, E7EXA8
    Related
    ENSP00000481695.1, ENST00000621732.4
    Conserved Domains (1) summary
    pfam15240
    Location:89 → 176
    Pro-rich; Proline-rich

  2. NM_002723.6 → NP_002714.2  basic salivary proline-rich protein 4 isoform 1 preproprotein

    See identical proteins and their annotated locations for NP_002714.2

    Status: REVIEWED

    Description
    Transcript Variant: This variant (1) represents the longer transcript and encodes the longer isoform (1).
    Source sequence(s)
    AC010176
    Consensus CDS
    CCDS8641.1
    UniProtKB/TrEMBL
    E9PAL0
    Related
    ENSP00000279575.1, ENST00000279575.7
    Conserved Domains (1) summary
    pfam15240
    Location:68 → 170
    Pro-rich; Proline-rich

RefSeqs of Annotated Genomes: GCF_000001405.40-RS_2024_08

The following sections contain reference sequences that belong to a specific genome build. Explain

Reference GRCh38.p14 Primary Assembly

Genomic

  1. NC_000012.12 Reference GRCh38.p14 Primary Assembly

    Range
    11307077..11310436 complement
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Reference GRCh38.p14 ALT_REF_LOCI_2

Genomic

  1. NT_187658.1 Reference GRCh38.p14 ALT_REF_LOCI_2

    Range
    502040..505399 complement
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060936.1 Alternate T2T-CHM13v2.0

    Range
    11176189..11179610 complement
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)
Nucleotide Protein
Heading Accession and Version
Protein Accession Links
GenPept Link UniProtKB Link
P10163.4 GenPept UniProtKB/Swiss-Prot:P10163

Gene LinkOut

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