GPAA1 explained

Glycosylphosphatidylinositol anchor attachment 1 protein is a protein that in humans is encoded by the GPAA1 gene.^{[1] [2]}

Posttranslational glycosylphosphatidylinositol (GPI) anchor attachment serves as a general mechanism for linking proteins to the cell surface membrane. The protein encoded by this gene presumably functions in GPI anchoring at the GPI transfer step. The mRNA transcript is ubiquitously expressed in both fetal and adult tissues. The anchor attachment protein 1 contains an N-terminal signal sequence, 1 cAMP- and cGMP-dependent protein kinase phosphorylation site, 1 leucine zipper pattern, 2 potential N-glycosylation sites, and 8 putative transmembrane domains.

Interactions

GPAA1 has been shown to interact with PIGT^{[3] [4]} and PIGK.^{[4] [5]}

Further reading

• Hiroi Y, Komuro I, Chen R, Hosoda T, Mizuno T, Kudoh S, Georgescu SP, Medof ME, Yazaki Y . 6 . Molecular cloning of human homolog of yeast GAA1 which is required for attachment of glycosylphosphatidylinositols to proteins . FEBS Letters . 421 . 3 . 252–8 . January 1998 . 9468317 . 10.1016/S0014-5793(97)01576-7 . 30327972 .
• Inoue N, Ohishi K, Endo Y, Fujita T, Takeda J, Kinoshita T . Human and mouse GPAA1 (Glycosylphosphatidylinositol anchor attachment 1) genes: genomic structures, chromosome loci and the presence of a minor class intron . Cytogenetics and Cell Genetics . 84 . 3–4 . 199–205 . 1999 . 10393431 . 10.1159/000015258 . 23878595 .
• Ohishi K, Inoue N, Maeda Y, Takeda J, Riezman H, Kinoshita T . Gaa1p and gpi8p are components of a glycosylphosphatidylinositol (GPI) transamidase that mediates attachment of GPI to proteins . Molecular Biology of the Cell . 11 . 5 . 1523–33 . May 2000 . 10793132 . 14864 . 10.1091/mbc.11.5.1523 .
• Ohishi K, Inoue N, Kinoshita T . PIG-S and PIG-T, essential for GPI anchor attachment to proteins, form a complex with GAA1 and GPI8 . The EMBO Journal . 20 . 15 . 4088–98 . August 2001 . 11483512 . 149153 . 10.1093/emboj/20.15.4088 .
• Vainauskas S, Maeda Y, Kurniawan H, Kinoshita T, Menon AK . Structural requirements for the recruitment of Gaa1 into a functional glycosylphosphatidylinositol transamidase complex . The Journal of Biological Chemistry . 277 . 34 . 30535–42 . August 2002 . 12052837 . 10.1074/jbc.M205402200 . free .
• Ohishi K, Nagamune K, Maeda Y, Kinoshita T . Two subunits of glycosylphosphatidylinositol transamidase, GPI8 and PIG-T, form a functionally important intermolecular disulfide bridge . The Journal of Biological Chemistry . 278 . 16 . 13959–67 . April 2003 . 12582175 . 10.1074/jbc.M300586200 . free .
• Hong Y, Ohishi K, Kang JY, Tanaka S, Inoue N, Nishimura J, Maeda Y, Kinoshita T . 6 . Human PIG-U and yeast Cdc91p are the fifth subunit of GPI transamidase that attaches GPI-anchors to proteins . Molecular Biology of the Cell . 14 . 5 . 1780–9 . May 2003 . 12802054 . 165076 . 10.1091/mbc.E02-12-0794 .
• Vainauskas S, Menon AK . A conserved proline in the last transmembrane segment of Gaa1 is required for glycosylphosphatidylinositol (GPI) recognition by GPI transamidase . The Journal of Biological Chemistry . 279 . 8 . 6540–5 . February 2004 . 14660601 . 10.1074/jbc.M312191200 . free .
• Vainauskas S, Menon AK . Endoplasmic reticulum localization of Gaa1 and PIG-T, subunits of the glycosylphosphatidylinositol transamidase complex . The Journal of Biological Chemistry . 280 . 16 . 16402–9 . April 2005 . 15713669 . 10.1074/jbc.M414253200 . free .
• Ho JC, Cheung ST, Patil M, Chen X, Fan ST . Increased expression of glycosyl-phosphatidylinositol anchor attachment protein 1 (GPAA1) is associated with gene amplification in hepatocellular carcinoma . International Journal of Cancer . 119 . 6 . 1330–7 . September 2006 . 16642471 . 10.1002/ijc.22005 . 33616131 . free .

Notes and References

1. Hiroi Y, Komuro I, Matsushita I, Aburatani H, Hosoda T, Nakahori Y, Medof ME, Yazaki Y . 6 . Assignment of the human GPAA1 gene, which encodes a product required for the attachment of glycosylphosphatidylinositols to proteins, at 8q24 . Genomics . 54 . 2 . 354–5 . December 1998 . 9828142 . 10.1006/geno.1998.5490 .
2. Web site: Entrez Gene: GPAA1 glycosylphosphatidylinositol anchor attachment protein 1 homolog (yeast).
3. Ohishi K, Inoue N, Kinoshita T . PIG-S and PIG-T, essential for GPI anchor attachment to proteins, form a complex with GAA1 and GPI8 . The EMBO Journal . 20 . 15 . 4088–98 . August 2001 . 11483512 . 149153 . 10.1093/emboj/20.15.4088 .
4. Vainauskas S, Maeda Y, Kurniawan H, Kinoshita T, Menon AK . Structural requirements for the recruitment of Gaa1 into a functional glycosylphosphatidylinositol transamidase complex . The Journal of Biological Chemistry . 277 . 34 . 30535–42 . August 2002 . 12052837 . 10.1074/jbc.M205402200 . free .
5. Ohishi K, Inoue N, Maeda Y, Takeda J, Riezman H, Kinoshita T . Gaa1p and gpi8p are components of a glycosylphosphatidylinositol (GPI) transamidase that mediates attachment of GPI to proteins . Molecular Biology of the Cell . 11 . 5 . 1523–33 . May 2000 . 10793132 . 14864 . 10.1091/mbc.11.5.1523 .