XK (protein)

Last updated
XK (protein)
Identifiers
SymbolXK
Alt. symbolsXKR1, Kx, X1k
NCBI gene 7504
HGNC 12811
OMIM 314850
PDB BAE48708
RefSeq NM_021083
UniProt P51811
Other data
Locus Chr. X p21.2-p21.1

XK (also known as Kell blood group precursor) is a protein found on human red blood cells and other tissues which is responsible for the Kx antigen which helps determine a person's blood type.

Contents

Clinical significance

The Kx antigen plays a role in matching blood for blood transfusions.[ citation needed ]

Mutation of XK protein may lead to McLeod syndrome, [1] a multi-system disorder characterized by hemolytic anemia, myopathy, acanthocytosis, and chorea. [2]

XK is located on the X chromosome (cytogenetic band Xp21.1) and absence of the XK protein is an X-linked disease. [3]

Function

XK is a membrane transport protein of unknown action. [4]

Related Research Articles

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McLeod syndrome Medical condition

McLeod syndrome is an X-linked recessive genetic disorder that may affect the blood, brain, peripheral nerves, muscle, and heart. It is caused by a variety of recessively inherited mutations in the XK gene on the X chromosome. The gene is responsible for producing the Kx protein, a secondary supportive protein for the Kell antigen on the red blood cell surface.

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The KX Blood-group Antigen (KXA) Family (TC# 2.A.112) consists of transport proteins that are part of the TOG superfamily. The KX gene codes for a novel protein with characteristics of membrane transporters that has been proposed to be a Na+ -dependent neutral amine and/or oligopeptide transporter. It is predicted to be 444 amino acyl residues in length and exhibits 10 putative transmembrane α-helical segments. The KX blood group antigen mRNA expression pattern correlates with McLeod syndrome.

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References

  1. Arnaud L, Salachas F, Lucien N, et al. (March 2009). "Identification and characterization of a novel XK splice site mutation in a patient with McLeod syndrome". Transfusion. 49 (3): 479–84. doi:10.1111/j.1537-2995.2008.02003.x. PMID   19040496. S2CID   27198922.
  2. Malandrini, A; Fabrizi, GM; Truschi, F; Di Pietro, G; Moschini, F; Bartalucci, P; Berti, G; Salvadori, C; et al. (1994). "Atypical McLeod syndrome manifested as X-linked chorea-acanthocytosis, neuromyopathy and dilated cardiomyopathy: report of a family". Journal of the Neurological Sciences. 124 (1): 89–94. doi:10.1016/0022-510X(94)90016-7. PMID   7931427. S2CID   27859436.
  3. Ho, MF; Monaco, AP; Blonden, LA; Van Ommen, GJ; Affara, NA; Ferguson-Smith, MA; Lehrach, H (1992). "Fine mapping of the McLeod locus (XK) to a 150-380-kb region in Xp21". American Journal of Human Genetics. 50 (2): 317–30. PMC   1682457 . PMID   1734714.
  4. Jung, HH; Russo, D; Redman, C; Brandner, S (2001). "Kell and XK immunohistochemistry in McLeod myopathy". Muscle & Nerve. 24 (10): 1346–51. doi:10.1002/mus.1154. PMID   11562915. S2CID   44749645.