Basic Information

Symbol
SMR3B
RNA class
mRNA
Alias
Submaxillary Gland Androgen Regulated Protein 3B PRL3 PROL3 P-B Submaxillary Gland Androgen-Regulated Protein 3B Proline-Rich Peptide P-B Proline-Rich Protein 3 Proline Rich 3 PBII Submaxillary Gland Androgen Regulated Protein 3 Homolog B (Mouse) Submaxillary Gland Androgen Regulated Protein 3 Homolog B Salivary Proline-Rich Protein SMR1B
Location (GRCh38)
4:70370093-70390244
UCSC Genome Browser Search in Marker Scope
Forensic tag(s)
Tissue/body fluid identification
External database
HGNC NCBI Ensembl OMIM UniProt GTEx

MANE select

Transcript ID
NM_006685.4
Sequence length
732.0 nt
GC content
0.4740

Secondary Structure

Generated by RNAfold
Minimum free energy (MFE) structure:
Secondary structure that contributes a minimum of free energy.
Ensemble properties:
Thermodynamic properties of the Boltzmann ensemble.
Minimum free energy
-162.3 kcal/mol
Thermodynamic ensemble
Free energy: -177.71 kcal/mol
Frequency: 0.0000
Diversity: 159.44
MFE Structure Visualization
Structure Prediction
MFE Structure Prediction
..(((((((((((.((((((..(((((((((....))))).))))(((.........))).....(((.(((((.......)))).).)))..((((.((.......((..(((((((((((((....(((((((((((.((((...)))))).)))))))))...((((..((((.((.(((........))).)).))))..))))...........))))))))))))).)).......)).)))).........(((((((((((........))).............((.(((((..((((............................(((.............((((......)))).............))))))))))))))..........))))))))...((((((((((((((((((((........................(((((.................)))))..((((....))))........................(((.....))).......................................)))).))))))........((((.((((((((((..............))))))))))..))))...)))))))))).......))))))...((((...........)))).......((((......)))).))))..))))))).............
Thermodynamic Ensemble Prediction
..(((((((((((.((((((..(((((((((....))))).)))),{(,,,......|||,...,|||.,((((.......)))).,.}}}..(((({({.......{,..{(((((((((((({({.(((((((((((.((((...))))))},))))))))..}||||,,|{{({((,{{(,,,,...,|||{||,,}||..}}}}.....,,....))}}})))},,||..,.......}}.},,,.........||{,,,(((((..............}}}}}..,,}...,))||}|||||},,.,,,....................,}))}}},......,,,|||{......}|||{|......,}}}},,,,...,,....}......,,...,}))},,...{(((((((((((((((((((.....,..................(((((.................)))))..((((....}}})........,{..............||,.....,},.,................|............,.......)))).)))))),.......((((.((((((((((..............))))))))))..))))..,))))))))})..}}|..))))))..,((((,..........)))),......{{{{......}))).))))}.,)))))).............

Transcripts

ID Sequence Length GC content
NM_006685.4 NCBI
ACCUUUAUUUGCCGUCUUUCAACUGGCAAGAGUCAUUUUGACCAGCAGA… 732 nt 0.4740
Summary

Predicted to enable endopeptidase inhibitor activity. Predicted to be involved in cellular response to lipopolysaccharide; negative regulation of peptidase activity; and regulation of sensory perception of pain. Located in extracellular exosome. [provided by Alliance of Genome Resources, Jul 2025]

Forensic Context

A study in humans identified the SMR3B as a novel absolute specific mRNA marker for saliva through transcriptomic sequencing of forensic body fluids [Liu et al. DOI:10.1007/s00414-023-03131-w]. A separate human study using targeted high-resolution mass spectrometry validated the SMR3B protein as a particularly reliable and robust marker for saliva identification, detecting it in all 50 saliva samples tested, including in aged and diluted casework-type samples [Brown et al. DOI:10.1021/acs.jproteome.5c00711].