Seroatlas · Human Serome Atlas

XKR6

XK-related protein 6

Also known as: C8orf21, C8orf5, C8orf7, XKR6_HUMAN

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

Protein identityUniProt · HPA

UniProt accession: Q5GH73
Gene: XKR6
Ensembl: ENSG00000171044
Chromosome: 8
Canonical length: 641 aa
Protein class: Predicted membrane proteins
Subcellular location: Actin filaments

OverviewNCBI Gene

Predicted to be involved in apoptotic process involved in development; engulfment of apoptotic cell; and phosphatidylserine exposure on apoptotic cell surface. Predicted to be located in membrane. Predicted to be active in plasma membrane. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

641 residues, UniProt reviewed canonical sequence.

>Q5GH73|XKR6
     1  MAAKSDGGGV GVGFAQLHNL DEAVGSGGEE DGEPGGGGCG GGGDGSEPGE SSSMHICHCC
    61  NTSSCYWGCR SACLRSLLGR KPRRSAAADG GDQPLQPPAA PGAGRQPPTP SAARPEPPPP
   121  QVERPWLDCL WIVLALLVFF GDVGTDLWLA LDYYRKGDYV YFGLTLFFVL VPSLLVQSLS
   181  FRWFVQDYTG GGLGAVEGLT SRGPPMMGAG YVHGAARGGP GVRVSPTPGA QRLCRLSVWI
   241  WQSVIHLLQM GQVWRYIRTM YLGIQSQRRK EHQRRFYWAM MYEYADVNML RLLETFLESA
   301  PQLVLQLYIM LQKNSAETLP CVSSVTSLMS LAWVLASYHK LLRDSRDDKK SMSYRGAIIQ
   361  VFWRLFTISS RVISFALFAS IFQLYFGIFV VVHWCAMAFW IIHGGTDFCM SKWEEILFNM
   421  VVGIVYIFCW FNVKEGRTRY RMFAYYTIVL TENAALTFLW YFYRDPETTD SYAVPALCCV
   481  FISFVAGIAM MLLYYGVLHP TGPRAKILAS SCCAELLWGI PLPPDVEPMA PEIPGYRGTQ
   541  VTPTRAVTEQ QEDLTADTCL PVFQVRPMGP PTPLGRPYLP EGPLIKIDMP RKRYPAWDAH
   601  FVDRRLRRTI NILQYVTPTA VGIRYRDGPL LYELLQYESS L

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against XKR6 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: Cell surface
Secreted: No
Transmembrane segments: 7
Mean surface accessibility (rSASA): 0.41
Highest tissue expression: 2.1 nTPM

Expression across tissuesHPA

Tissue

testis: 2.1 nTPM
pancreas: 1.3 nTPM
cerebellum: 0.9 nTPM
esophagus: 0.9 nTPM
salivary gland: 0.9 nTPM
skin: 0.8 nTPM

Single-cell type

brain excitatory neurons: 543 nCPM
brain inhibitory neurons: 518 nCPM
other brain neurons: 482 nCPM
distal convoluted tubule cells: 482 nCPM
podocytes: 409 nCPM
oligodendrocyte progenitor cells: 385 nCPM

Immune cell

memory B-cell: 0.1 nTPM
naive B-cell: 0.1 nTPM
NK-cell: 0.1 nTPM
basophil: 0 nTPM
classical monocyte: 0 nTPM
eosinophil: 0 nTPM

Brain region

cerebellum: 41 nTPM
hypothalamus: 24 nTPM
basal ganglia: 22 nTPM
cerebral cortex: 22 nTPM
hippocampal formation: 20 nTPM
pons: 19 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): 0.19
gnomAD pLI: 1
gnomAD missense Z: 2.01
DepMap mean gene effect: 0.05
DepMap dependency class: none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Cellular components

plasma membrane

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads XKR6 as an antibody target. Whether an autoantibody or antibody against XKR6 could matter depends on whether native XKR6 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

XKR6 is annotated at the cell surface, where native XKR6 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label XKR6 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Loading the interactive Seroatlas protein explorer...