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Gene Review

Piga  -  phosphatidylinositol glycan anchor...

Mus musculus

Synonyms: AI194334, GlcNAc-PI synthesis protein, N-acetylglucosaminyl-phosphatidylinositol biosynthetic protein, PIG-A, Phosphatidylinositol-glycan biosynthesis class A protein, ...
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Disease relevance of Piga

  • GATA1-Cre mediates Piga gene inactivation in the erythroid/megakaryocytic lineage and leads to circulating red cells with a partial deficiency in glycosyl phosphatidylinositol-linked proteins (paroxysmal nocturnal hemoglobinuria type II cells) [1].
  • Finally, since the dual abnormalities in the lamellar body secretory system and filaggrin processing resemble two key features of human Harlequin ichthyosis, Pig-a null mice could provide an appropriate analog for further studies of this disease [2].
  • Female embryos in which one Pig-a allele was disrupted by Cre such that only half of the cells in the embryo proper did not express GPI-anchored proteins due to random X inactivation developed until 19 days post coitum (dpc), but showed abnormal phenotypes such as insufficient closure of neural tube and cleft palate [3].
  • Currently there is no experimental animal model for studying paroxysmal nocturnal hemoglobinuria (PNH), an acquired hemolytic anemia linked to mutations of the PIG-A gene [4].
  • Direct evidence for the involvement of GPI or GPI-anchored proteins in the HgCl2-mediated signaling is provided by the loss of signaling in a mutant thymoma cell line defective in the phosphatidylinositol glycan-class A gene (PIG-A), and its restoration in a transfectant with PIG-A [5].

High impact information on Piga


Biological context of Piga


Anatomical context of Piga


Associations of Piga with chemical compounds

  • Mice with targeted Piga gene inactivation genetically mimic the human disease and have phosphatidylinositol glycan class A-negative (PIGA-) RBCs with a reduced half-life in circulation [16].
  • All patients with PNH studied so far have a somatic mutation of phosphatidyl inositol glycan complementation group A (PIG-A), an X-linked gene involved initially in the biosynthesis of the glycosyl phosphatidylinositol (GPI) molecule, which serves as an anchor for many cell surface proteins [17].

Other interactions of Piga

  • In contrast to Piga, both human and mouse Pigf and Pigh genes map to autosomes [9].
  • In summary, GATA1-Cre causes high-efficiency Piga gene inactivation in a GATA-1-specific pattern [1].
  • Here we analyzed keratinocytes of the female K5-Cre: Pig-a flox/+ mice with heterozygous knockout of Pig-a. These cells exhibited the mosaic pattern of GPI-anchor positive and negative expression typical of random inactivation of the X chromosome [18].

Analytical, diagnostic and therapeutic context of Piga

  • We therefore treated mice that have a proportion of blood cells deficient in GPI-anchor molecules (PIGA-) with HD CY, and monitored their peripheral blood counts during and after treatment [12].
  • We therefore used site-directed mutagenesis to create conservative mutations in the Pig-a protein, then performed structural and functional analysis [19].
  • DNA chip analysis of multiple paired normal and PIG-A mutant cell lines and lymphoblastoid cells do not show any consistent differences in levels of gene expression [20].


  1. GATA1-Cre mediates Piga gene inactivation in the erythroid/megakaryocytic lineage and leads to circulating red cells with a partial deficiency in glycosyl phosphatidylinositol-linked proteins (paroxysmal nocturnal hemoglobinuria type II cells). Jasinski, M., Keller, P., Fujiwara, Y., Orkin, S.H., Bessler, M. Blood (2001) [Pubmed]
  2. Epidermal-specific defect of GPI anchor in Pig-a null mice results in Harlequin ichthyosis-like features. Hara-Chikuma, M., Takeda, J., Tarutani, M., Uchida, Y., Holleran, W.M., Endo, Y., Elias, P.M., Inoue, S. J. Invest. Dermatol. (2004) [Pubmed]
  3. Developmental abnormalities of glycosylphosphatidylinositol-anchor-deficient embryos revealed by Cre/loxP system. Nozaki, M., Ohishi, K., Yamada, N., Kinoshita, T., Nagy, A., Takeda, J. Lab. Invest. (1999) [Pubmed]
  4. Cloning and characterization of the mouse PIG-A gene. Yu, J., Nagarajan, S., Liu, J., Young, N., Medof, M.E. Biochim. Biophys. Acta (1995) [Pubmed]
  5. Direct evidence of involvement of glycosylphosphatidylinositol-anchored proteins in the heavy metal-mediated signal delivery into T lymphocytes. Pu, M., Ma, L., Ohkusu, K., Isobe, K., Taguchi, R., Ikezawa, H., Hamaguchi, M., Nakashima, I. FEBS Lett. (1995) [Pubmed]
  6. Deficiency of the GPI anchor caused by a somatic mutation of the PIG-A gene in paroxysmal nocturnal hemoglobinuria. Takeda, J., Miyata, T., Kawagoe, K., Iida, Y., Endo, Y., Fujita, T., Takahashi, M., Kitani, T., Kinoshita, T. Cell (1993) [Pubmed]
  7. FES-Cre targets phosphatidylinositol glycan class A (PIGA) inactivation to hematopoietic stem cells in the bone marrow. Keller, P., Payne, J.L., Tremml, G., Greer, P.A., Gaboli, M., Pandolfi, P.P., Bessler, M. J. Exp. Med. (2001) [Pubmed]
  8. Murine embryonic stem cells without pig-a gene activity are competent for hematopoiesis with the PNH phenotype but not for clonal expansion. Rosti, V., Tremml, G., Soares, V., Pandolfi, P.P., Luzzatto, L., Bessler, M. J. Clin. Invest. (1997) [Pubmed]
  9. Chromosomal assignment of genes involved in glycosylphosphatidylinositol anchor biosynthesis: implications for the pathogenesis of paroxysmal nocturnal hemoglobinuria. Ware, R.E., Howard, T.A., Kamitani, T., Change, H.M., Yeh, E.T., Seldin, M.F. Blood (1994) [Pubmed]
  10. X inactivation and somatic cell selection rescue female mice carrying a Piga-null mutation. Keller, P., Tremml, G., Rosti, V., Bessler, M. Proc. Natl. Acad. Sci. U.S.A. (1999) [Pubmed]
  11. The effect of GPI-anchor deficiency on apoptosis in mice carrying a Piga gene mutation in hematopoietic cells. Kulkarni, S., Bessler, M. J. Leukoc. Biol. (2002) [Pubmed]
  12. High-dose cyclophosphamide does not eradicate paroxysmal nocturnal haemoglobinuria haematopoiesis in mice carrying a Piga gene mutation. Schaefer, A., Jasinski, M., Bessler, M. Br. J. Haematol. (2003) [Pubmed]
  13. Tissue-specific knockout of the mouse Pig-a gene reveals important roles for GPI-anchored proteins in skin development. Tarutani, M., Itami, S., Okabe, M., Ikawa, M., Tezuka, T., Yoshikawa, K., Kinoshita, T., Takeda, J. Proc. Natl. Acad. Sci. U.S.A. (1997) [Pubmed]
  14. Increased sensitivity to complement and a decreased red blood cell life span in mice mosaic for a nonfunctional Piga gene. Tremml, G., Dominguez, C., Rosti, V., Zhang, Z., Pandolfi, P.P., Keller, P., Bessler, M. Blood (1999) [Pubmed]
  15. Different roles of glycosylphosphatidylinositol in various hematopoietic cells as revealed by a mouse model of paroxysmal nocturnal hemoglobinuria. Murakami, Y., Kinoshita, T., Maeda, Y., Nakano, T., Kosaka, H., Takeda, J. Blood (1999) [Pubmed]
  16. A novel mechanism of complement-independent clearance of red cells deficient in glycosyl phosphatidylinositol-linked proteins. Jasinski, M., Pantazopoulos, P., Rother, R.P., van Rooijen, N., Song, W.C., Molina, H., Bessler, M. Blood (2004) [Pubmed]
  17. Murine models of paroxysmal nocturnal hemoglobinuria. Rosti, V. Ann. N. Y. Acad. Sci. (2002) [Pubmed]
  18. Rapid compensation for glycosylphosphatidylinositol anchor deficient keratinocytes after birth: visualization of glycosylphosphatidylinositol-anchored proteins in situ. Gao, X.H., Kondoh, G., Tarutani, M., Hara, M., Inoue, S., Nakanishi, T., Okabe, M., Yamaguchi, Y., Yoshikawa, K., Itami, S., Takeda, J. J. Invest. Dermatol. (2002) [Pubmed]
  19. Structural and functional analysis of the Pig-a protein that is mutated in paroxysmal nocturnal hemoglobinuria. Norris, E.R., Howard, T.A., Marcus, S.J., Ware, R.E. Blood Cells Mol. Dis. (1997) [Pubmed]
  20. The relationship of aplastic anemia and PNH. Young, N.S., Maciejewski, J.P., Sloand, E., Chen, G., Zeng, W., Risitano, A., Miyazato, A. Int. J. Hematol. (2002) [Pubmed]
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