F8A1 explained

40-kDa huntingtin-associated protein also known as (Coagulation factor VIII associated 1) is a protein that in humans is encoded by the F8A1, F8A2, and F8A3 genes.^{[1] [2] [3] [4]}

F8A1 is contained entirely within intron 22 of the factor VIII gene; spans less than 2 kb, and is transcribed in the direction opposite of factor VIII. A portion of intron 22 (int22h), containing F8A1, is repeated twice extragenically closer to the Xq telomere (genes F8A2, F8A3). Although its function is unknown, the observation that this gene is conserved in the mouse implies it has some function. Unlike factor VIII, this gene is transcribed abundantly in a wide variety of cell types.

Further reading

• Levinson B . Evidence for a third transcript from the human factor VIII gene . Genomics . 14 . 3 . 585–9 . 1992 . 1427887 . 10.1016/S0888-7543(05)80155-7 . Kenwrick S . Gamel P . Fisher . Karen . Gitschier . Jane .
• Levinson B . Sequence of the human factor VIII-associated gene is conserved in mouse . Genomics . 13 . 3 . 862–5 . 1992 . 1639415 . 10.1016/0888-7543(92)90170-W . Bermingham JR . Metzenberg A . Kenwrick . Susan . Chapman . Verne . Gitschier . Jane .
• Naylor JA . Investigation of the factor VIII intron 22 repeated region (int22h) and the associated inversion junctions . Hum. Mol. Genet. . 4 . 7 . 1217–24 . 1996 . 8528212 . 10.1093/hmg/4.7.1217 . Buck D . Green P . Williamson . Helen . Bentley . David . Gianneill . Francesco .
• Peters MF, Ross CA . Isolation of a 40-kDa Huntingtin-associated protein . J. Biol. Chem. . 276 . 5 . 3188–94 . 2001 . 11035034 . 10.1074/jbc.M008099200 . free .
• Hartley JL, Temple GF, Brasch MA . DNA cloning using in vitro site-specific recombination . Genome Res. . 10 . 11 . 1788–95 . 2001 . 11076863 . 10.1101/gr.143000 . 310948 .
• Simpson JC . Systematic subcellular localization of novel proteins identified by large-scale cDNA sequencing . EMBO Rep. . 1 . 3 . 287–92 . 2001 . 11256614 . 10.1093/embo-reports/kvd058 . 1083732 . Wellenreuther R . Poustka A . Pepperkok . R . Wiemann . S .
• Strausberg RL . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences . Proc. Natl. Acad. Sci. U.S.A. . 99 . 26 . 16899–903 . 2003 . 12477932 . 10.1073/pnas.242603899 . 139241 . Feingold EA . Grouse LH . Derge . JG . Klausner . RD . Collins . FS . Wagner . L . Shenmen . CM . Schuler . GD . 2002PNAS...9916899M . free .
• Jenkins PV, Dill JL, Zhou Q, Fay PJ . Clustered basic residues within segment 484-510 of the factor VIIIa A2 subunit contribute to the catalytic efficiency for factor Xa generation . J. Thromb. Haemost. . 2 . 3 . 452–8 . 2004 . 15009463 . 10.1111/j.1538-7933.2004.00625.x . factor Xa . 32607321 .
• Gerhard DS . The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC) . Genome Res. . 14 . 10B . 2121–7 . 2004 . 15489334 . 10.1101/gr.2596504 . 528928 . Wagner L . Feingold EA . Shenmen . CM . Grouse . LH . Schuler . G . Klein . SL . Old . S . Rasooly . R .
• Wiemann S . From ORFeome to biology: a functional genomics pipeline . Genome Res. . 14 . 10B . 2136–44 . 2004 . 15489336 . 10.1101/gr.2576704 . 528930 . Arlt D . Huber W . Wellenreuther . R . Schleeger . S . Mehrle . A . Bechtel . S . Sauermann . M . Korf . U .
• Bagnall RD, Ayres KL, Green PM, Giannelli F . Gene conversion and evolution of Xq28 duplicons involved in recurring inversions causing severe hemophilia A . Genome Res. . 15 . 2 . 214–23 . 2005 . 15687285 . 10.1101/gr.2946205 . 546521 .
• Mehrle A . The LIFEdb database in 2006 . Nucleic Acids Res. . 34 . Database issue . D415–8 . 2006 . 16381901 . 10.1093/nar/gkj139 . 1347501 . Rosenfelder H . Schupp I . Del Val . C . Arlt . D . Hahne . F . Bechtel . S . Simpson . J . Hofmann . O .
• Brown V . Binding specificity of Toll-like receptor cytoplasmic domains . Eur. J. Immunol. . 36 . 3 . 742–53 . 2006 . 16482509 . 10.1002/eji.200535158 . 2762736 . Brown RA . Ozinsky A . Hesselberth . Jay R. . Fields . Stanley .
• Parker ET, Doering CB, Lollar P . A1 subunit-mediated regulation of thrombin-activated factor VIII A2 subunit dissociation . J. Biol. Chem. . 281 . 20 . 13922–30 . 2006 . 16513639 . 10.1074/jbc.M513124200 . free .

Notes and References

1. Levinson B, Kenwrick S, Lakich D, ((Hammonds G Jr)), Gitschier J . A transcribed gene in an intron of the human factor VIII gene . Genomics . 7 . 1 . 1–11 . Jun 1990 . 2110545 . 10.1016/0888-7543(90)90512-S .
2. Web site: F8A1 coagulation factor VIII associated 1 [Homo sapiens (human) ]].
3. Web site: F8A2 coagulation factor VIII associated 2 [Homo sapiens (human) ]].
4. Web site: F8A3 coagulation factor VIII associated 3 [Homo sapiens (human) ]].