Seroatlas · Human Serome Atlas

PRPSAP1

Phosphoribosyl pyrophosphate synthase-associated protein 1

Also known as: KPRA_HUMAN, PAP39

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession: Q14558
Gene: PRPSAP1
Ensembl: ENSG00000161542
Chromosome: 17
Canonical length: 356 aa
Protein class: Predicted intracellular proteins
Subcellular location: Cytosol

OverviewNCBI Gene

Enables identical protein binding activity. Predicted to be involved in 5-phosphoribose 1-diphosphate biosynthetic process and purine nucleotide biosynthetic process. Predicted to be active in cytoplasm. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

356 residues, UniProt reviewed canonical sequence.

>Q14558|PRPSAP1
     1  MNAARTGYRV FSANSTAACT ELAKRITERL GAELGKSVVY QETNGETRVE IKESVRGQDI
    61  FIIQTIPRDV NTAVMELLIM AYALKTACAR NIIGVIPYFP YSKQSKMRKR GSIVCKLLAS
   121  MLAKAGLTHI ITMDLHQKEI QGFFSFPVDN LRASPFLLQY IQEEIPNYRN AVIVAKSPDA
   181  AKRAQSYAER LRLGLAVIHG EAQCTELDMD DGRHSPPMVK NATVHPGLEL PLMMAKEKPP
   241  ITVVGDVGGR IAIIVDDIID DVESFVAAAE ILKERGAYKI YVMATHGILS AEAPRLIEES
   301  SVDEVVVTNT VPHEVQKLQC PKIKTVDISL ILSEAIRRIH NGESMAYLFR NITVDD

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against PRPSAP1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability: Intracellular
Secreted: No
Transmembrane segments: 0
Mean surface accessibility (rSASA): 0.28
Highest tissue expression: 65 nTPM

Expression across tissuesHPA

Tissue

liver: 65 nTPM
salivary gland: 62 nTPM
thyroid gland: 46 nTPM
parathyroid gland: 41 nTPM
testis: 34 nTPM
choroid plexus: 34 nTPM

Single-cell type

esophageal apical cells: 251 nCPM
müller glia: 212 nCPM
oocytes: 166 nCPM
late primary spermatocytes: 129 nCPM
differentiating spermatogonia: 124 nCPM
salivary myoepithelial cells: 121 nCPM

Immune cell

T-reg: 25 nTPM
eosinophil: 22 nTPM
NK-cell: 19 nTPM
basophil: 18 nTPM
MAIT T-cell: 17 nTPM
memory B-cell: 17 nTPM

Brain region

pons: 39 nTPM
thalamus: 34 nTPM
hypothalamus: 32 nTPM
medulla oblongata: 32 nTPM
midbrain: 32 nTPM
white matter: 30 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance): 1.29
gnomAD pLI: 0
gnomAD missense Z: 1.67
DepMap mean gene effect: -0.01
DepMap dependency class: selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 10% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

cytoplasm

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of PRPSAP1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads PRPSAP1 as an antibody target. Whether an autoantibody or antibody against PRPSAP1 could matter depends on whether native PRPSAP1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

PRPSAP1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label PRPSAP1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...