Seroatlas · Human Serome Atlas

CHM

Rab proteins geranylgeranyltransferase component A 1

Also known as: DXS540, RAE1_HUMAN, REP-1, TCD

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

Protein identityUniProt · HPA

UniProt accession
P24386
Gene
CHM
Ensembl
ENSG00000188419
Chromosome
X
Canonical length
653 aa
Protein class
Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Cytosol

OverviewNCBI Gene

This gene encodes component A of the RAB geranylgeranyl transferase holoenzyme. In the dimeric holoenzyme, this subunit binds unprenylated Rab GTPases and then presents them to the catalytic Rab GGTase subunit for the geranylgeranyl transfer reaction. Rab GTPases need to be geranylgeranyled on either one or two cysteine residues in their C-terminus to localize to the correct intracellular membrane. Mutations in this gene are a cause of choroideremia; also known as tapetochoroidal dystrophy (TCD). This X-linked disease is characterized by progressive dystrophy of the choroid, retinal pigment epithelium and retina. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Mar 2016]

Canonical amino-acid sequenceUniProt

653 residues, UniProt reviewed canonical sequence.

>P24386|CHM
     1  MADTLPSEFD VIVIGTGLPE SIIAAACSRS GRRVLHVDSR SYYGGNWASF SFSGLLSWLK
    61  EYQENSDIVS DSPVWQDQIL ENEEAIALSR KDKTIQHVEV FCYASQDLHE DVEEAGALQK
   121  NHALVTSANS TEAADSAFLP TEDESLSTMS CEMLTEQTPS SDPENALEVN GAEVTGEKEN
   181  HCDDKTCVPS TSAEDMSENV PIAEDTTEQP KKNRITYSQI IKEGRRFNID LVSKLLYSRG
   241  LLIDLLIKSN VSRYAEFKNI TRILAFREGR VEQVPCSRAD VFNSKQLTMV EKRMLMKFLT
   301  FCMEYEKYPD EYKGYEEITF YEYLKTQKLT PNLQYIVMHS IAMTSETASS TIDGLKATKN
   361  FLHCLGRYGN TPFLFPLYGQ GELPQCFCRM CAVFGGIYCL RHSVQCLVVD KESRKCKAII
   421  DQFGQRIISE HFLVEDSYFP ENMCSRVQYR QISRAVLITD RSVLKTDSDQ QISILTVPAE
   481  EPGTFAVRVI ELCSSTMTCM KGTYLVHLTC TSSKTAREDL ESVVQKLFVP YTEMEIENEQ
   541  VEKPRILWAL YFNMRDSSDI SRSCYNDLPS NVYVCSGPDC GLGNDNAVKQ AETLFQEICP
   601  NEDFCPPPPN PEDIILDGDS LQPEASESSA IPEANSETFK ESTNLGNLEE SSE

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CHM 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)
0.34
Highest tissue expression
13 nTPM

Expression across tissuesHPA

Tissue

  • parathyroid gland: 13 nTPM
  • kidney: 11 nTPM
  • cerebral cortex: 11 nTPM
  • adrenal gland: 11 nTPM
  • fallopian tube: 10 nTPM
  • thyroid gland: 10 nTPM

Single-cell type

  • gonadotrophs: 202 nCPM
  • somatotrophs: 193 nCPM
  • lactotrophs: 161 nCPM
  • corticotrophs: 158 nCPM
  • thyrotrophs: 156 nCPM
  • ependymal cells: 146 nCPM

Immune cell

  • intermediate monocyte: 2.3 nTPM
  • basophil: 2.1 nTPM
  • naive B-cell: 2.1 nTPM
  • classical monocyte: 1.8 nTPM
  • memory B-cell: 1.8 nTPM
  • naive CD8 T-cell: 1.8 nTPM

Brain region

  • cerebral cortex: 24 nTPM
  • choroid plexus: 23 nTPM
  • hippocampal formation: 23 nTPM
  • basal ganglia: 22 nTPM
  • white matter: 21 nTPM
  • pons: 21 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CHM.

Disease | AllUniProt

Conditions CHM is implicated in, by any mechanism.

Disease | GeneticClinVar

320 pathogenic / likely-pathogenic of 1,056 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.19
gnomAD pLI
1
gnomAD missense Z
0.79
DepMap mean gene effect
-0.03
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

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

CHM 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 CHM as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CHM. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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