Seroatlas · Human Serome Atlas

RNPEP

Aminopeptidase B

Also known as: AMPB_HUMAN, APB

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

Protein identityUniProt · HPA

UniProt accession: Q9H4A4
Gene: RNPEP
Ensembl: ENSG00000176393
Chromosome: 1
Canonical length: 650 aa
Protein class: Enzymes, Metabolic proteins, Plasma proteins, Predicted intracellular proteins, Predicted secreted proteins
Subcellular location: Golgi apparatus,Principal piece,End piece
Secretome location: Secreted - unknown location

OverviewNCBI Gene

Predicted to enable metalloaminopeptidase activity. Predicted to be involved in proteolysis. Located in extracellular exosome. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

650 residues, UniProt reviewed canonical sequence.

>Q9H4A4|RNPEP
     1  MASGEHSPGS GAARRPLHSA QAVDVASASN FRAFELLHLH LDLRAEFGPP GPGAGSRGLS
    61  GTAVLDLRCL EPEGAAELRL DSHPCLEVTA AALRRERPGS EEPPAEPVSF YTQPFSHYGQ
   121  ALCVSFPQPC RAAERLQVLL TYRVGEGPGV CWLAPEQTAG KKKPFVYTQG QAVLNRAFFP
   181  CFDTPAVKYK YSALIEVPDG FTAVMSASTW EKRGPNKFFF QMCQPIPSYL IALAIGDLVS
   241  AEVGPRSRVW AEPCLIDAAK EEYNGVIEEF LATGEKLFGP YVWGRYDLLF MPPSFPFGGM
   301  ENPCLTFVTP CLLAGDRSLA DVIIHEISHS WFGNLVTNAN WGEFWLNEGF TMYAQRRIST
   361  ILFGAAYTCL EAATGRALLR QHMDITGEEN PLNKLRVKIE PGVDPDDTYN ETPYEKGFCF
   421  VSYLAHLVGD QDQFDSFLKA YVHEFKFRSI LADDFLDFYL EYFPELKKKR VDIIPGFEFD
   481  RWLNTPGWPP YLPDLSPGDS LMKPAEELAQ LWAAEELDMK AIEAVAISPW KTYQLVYFLD
   541  KILQKSPLPP GNVKKLGDTY PSISNARNAE LRLRWGQIVL KNDHQEDFWK VKEFLHNQGK
   601  QKYTLPLYHA MMGGSEVAQT LAKETFASTA SQLHSNVVNY VQQIVAPKGS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against RNPEP 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: Secreted
Secreted: Yes
Transmembrane segments: 0
Mean surface accessibility (rSASA): 0.22
Highest tissue expression: 64 nTPM

Expression across tissuesHPA

Tissue

duodenum: 64 nTPM
small intestine: 55 nTPM
rectum: 54 nTPM
esophagus: 51 nTPM
colon: 50 nTPM
fallopian tube: 38 nTPM

Single-cell type

enterocytes: 208 nCPM
esophageal apical cells: 201 nCPM
cytotrophoblasts: 151 nCPM
esophageal suprabasal cells: 139 nCPM
colonocytes: 130 nCPM
migrating cytotrophoblasts: 129 nCPM

Immune cell

non-classical monocyte: 30 nTPM
intermediate monocyte: 26 nTPM
basophil: 23 nTPM
eosinophil: 22 nTPM
myeloid DC: 20 nTPM
classical monocyte: 15 nTPM

Brain region

choroid plexus: 32 nTPM
white matter: 23 nTPM
thalamus: 22 nTPM
medulla oblongata: 19 nTPM
midbrain: 18 nTPM
spinal cord: 18 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): 1.26
gnomAD pLI: 0
gnomAD missense Z: 0.69
DepMap mean gene effect: -0.11
DepMap dependency class: selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 11% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

proteolysis

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

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

RNPEP is annotated as secreted, so native RNPEP circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

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

Loading the interactive Seroatlas protein explorer...