APOM explained

Symbol:	ApoM
ApoM
Pfam:	PF11032
Pfam Clan:	CL0116
Interpro:	IPR022734

Apolipoprotein M is an apolipoprotein and member of the lipocalin protein family that in humans is encoded by the APOM gene.^{[1] [2] [3]} It is found associated with high density lipoproteins and to a lesser extent with low density lipoproteins and triglyceride-rich lipoproteins. The encoded protein is secreted through the plasma membrane but remains membrane-bound, where it is involved in lipid transport. Two transcript variants encoding two different isoforms have been found for this gene, but only one of them has been fully characterized. It lacks an external amphipathic motif and is uniquely secreted to plasma without cleavage of its terminal signal peptide.^[4] The average molecular weight is 21253 Da, and the monoisotopic molecular weight is 21239 Da.

Further reading

• Albertella MR, Jones H, Thomson W, Olavesen MG, Campbell RD . Localization of eight additional genes in the human major histocompatibility complex, including the gene encoding the casein kinase II beta subunit (CSNK2B) . Genomics . 36 . 2 . 240–251 . September 1996 . 8812450 . 10.1006/geno.1996.0459 .
• Xu N, Zhang XY, Dong X, Ekström U, Ye Q, Nilsson-Ehle P . Effects of platelet-activating factor, tumor necrosis factor, and interleukin-1alpha on the expression of apolipoprotein M in HepG2 cells . Biochemical and Biophysical Research Communications . 292 . 4 . 944–950 . April 2002 . 11944906 . 10.1006/bbrc.2002.6755 .
• Strausberg RL, Feingold EA, Grouse LH, Derge JG, Klausner RD, Collins FS, Wagner L, Shenmen CM, Schuler GD, Altschul SF, Zeeberg B, Buetow KH, Schaefer CF, Bhat NK, Hopkins RF, Jordan H, Moore T, Max SI, Wang J, Hsieh F, Diatchenko L, Marusina K, Farmer AA, Rubin GM, Hong L, Stapleton M, Soares MB, Bonaldo MF, Casavant TL, Scheetz TE, Brownstein MJ, Usdin TB, Toshiyuki S, Carninci P, Prange C, Raha SS, Loquellano NA, Peters GJ, Abramson RD, Mullahy SJ, Bosak SA, McEwan PJ, McKernan KJ, Malek JA, Gunaratne PH, Richards S, Worley KC, Hale S, Garcia AM, Gay LJ, Hulyk SW, Villalon DK, Muzny DM, Sodergren EJ, Lu X, Gibbs RA, Fahey J, Helton E, Ketteman M, Madan A, Rodrigues S, Sanchez A, Whiting M, Madan A, Young AC, Shevchenko Y, Bouffard GG, Blakesley RW, Touchman JW, Green ED, Dickson MC, Rodriguez AC, Grimwood J, Schmutz J, Myers RM, Butterfield YS, Krzywinski MI, Skalska U, Smailus DE, Schnerch A, Schein JE, Jones SJ, Marra MA . 6 . Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences . Proceedings of the National Academy of Sciences of the United States of America . 99 . 26 . 16899–16903 . December 2002 . 12477932 . 139241 . 10.1073/pnas.242603899 . free . 2002PNAS...9916899M .
• Zhang XY, Dong X, Zheng L, Luo GH, Liu YH, Ekström U, Nilsson-Ehle P, Ye Q, Xu N . 6 . Specific tissue expression and cellular localization of human apolipoprotein M as determined by in situ hybridization . Acta Histochemica . 105 . 1 . 67–72 . 2003 . 12666989 . 10.1078/0065-1281-00687 .
• Richter S, Shih DQ, Pearson ER, Wolfrum C, Fajans SS, Hattersley AT, Stoffel M . Regulation of apolipoprotein M gene expression by MODY3 gene hepatocyte nuclear factor-1alpha: haploinsufficiency is associated with reduced serum apolipoprotein M levels . Diabetes . 52 . 12 . 2989–2995 . December 2003 . 14633861 . 10.2337/diabetes.52.12.2989 . free .
• Xie T, Rowen L, Aguado B, Ahearn ME, Madan A, Qin S, Campbell RD, Hood L . 6 . Analysis of the gene-dense major histocompatibility complex class III region and its comparison to mouse . Genome Research . 13 . 12 . 2621–2636 . December 2003 . 14656967 . 403804 . 10.1101/gr.1736803 .
• Zhang XY, Jiao GQ, Hurtig M, Dong X, Zheng L, Luo GH, Nilsson-Ehle P, Ye Q, Xu N . 6 . Expression pattern of apolipoprotein M during mouse and human embryogenesis . Acta Histochemica . 106 . 2 . 123–128 . 2005 . 15147633 . 10.1016/j.acthis.2003.11.004 .
• Kabbara A, Payet N, Cottel D, Frigard B, Amouyel P, Lambert JC . Exclusion of CYP46 and APOM as candidate genes for Alzheimer's disease in a French population . Neuroscience Letters . 363 . 2 . 139–143 . June 2004 . 15172102 . 10.1016/j.neulet.2004.03.066 . 27752858 .
• Xu N, Nilsson-Ehle P, Ahrén B . Correlation of apolipoprotein M with leptin and cholesterol in normal and obese subjects . The Journal of Nutritional Biochemistry . 15 . 10 . 579–582 . October 2004 . 15542348 . 10.1016/j.jnutbio.2004.03.001 .
• Luo G, Hurtig M, Zhang X, Nilsson-Ehle P, Xu N . Leptin inhibits apolipoprotein M transcription and secretion in human hepatoma cell line, HepG2 cells . Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids . 1734 . 2 . 198–202 . May 2005 . 15904876 . 10.1016/j.bbalip.2005.02.005 .
• Liu T, Qian WJ, Gritsenko MA, Camp DG, Monroe ME, Moore RJ, Smith RD . Human plasma N-glycoproteome analysis by immunoaffinity subtraction, hydrazide chemistry, and mass spectrometry . Journal of Proteome Research . 4 . 6 . 2070–2080 . 2006 . 16335952 . 1850943 . 10.1021/pr0502065 .
• Niu N, Zhu X, Liu Y, Du T, Wang X, Chen D, Sun B, Gu HF, Liu Y . 6 . Single nucleotide polymorphisms in the proximal promoter region of apolipoprotein M gene (apoM) confer the susceptibility to development of type 2 diabetes in Han Chinese . Diabetes/Metabolism Research and Reviews . 23 . 1 . 21–25 . January 2007 . 16572495 . 10.1002/dmrr.641 . 21156244 .
• Christoffersen C, Nielsen LB, Axler O, Andersson A, Johnsen AH, Dahlbäck B . Isolation and characterization of human apolipoprotein M-containing lipoproteins . Journal of Lipid Research . 47 . 8 . 1833–1843 . August 2006 . 16682745 . 10.1194/jlr.M600055-JLR200 . free .
• Karlsson H, Lindqvist H, Tagesson C, Lindahl M . Characterization of apolipoprotein M isoforms in low-density lipoprotein . Journal of Proteome Research . 5 . 10 . 2685–2690 . October 2006 . 17022639 . 10.1021/pr060180x .
• Xu X, Ye Q, Xu N, He X, Luo G, Zhang X, Zhu J, Zhang Y, Nilsson-Ehle P . 6 . Effects of ischemia-reperfusion injury on apolipoprotein M expression in the liver . Transplantation Proceedings . 38 . 9 . 2769–2773 . November 2006 . 17112825 . 10.1016/j.transproceed.2006.08.133 .
• Ahnström J, Faber K, Axler O, Dahlbäck B . Hydrophobic ligand binding properties of the human lipocalin apolipoprotein M . Journal of Lipid Research . 48 . 8 . 1754–1762 . August 2007 . 17525477 . 10.1194/jlr.M700103-JLR200 . free .

External links

• Applied Research on apoM

Notes and References

1. Xu N, Dahlbäck B . A novel human apolipoprotein (apoM) . The Journal of Biological Chemistry . 274 . 44 . 31286–31290 . October 1999 . 10531326 . 10.1074/jbc.274.44.31286 . free .
2. Duan J, Dahlbäck B, Villoutreix BO . Proposed lipocalin fold for apolipoprotein M based on bioinformatics and site-directed mutagenesis . FEBS Letters . 499 . 1–2 . 127–132 . June 2001 . 11418126 . 10.1016/S0014-5793(01)02544-3 . 28493816 . free .
3. Web site: Entrez Gene: APOM apolipoprotein M.
4. Christoffersen C, Ahnström J, Axler O, Christensen EI, Dahlbäck B, Nielsen LB . The signal peptide anchors apolipoprotein M in plasma lipoproteins and prevents rapid clearance of apolipoprotein M from plasma . The Journal of Biological Chemistry . 283 . 27 . 18765–18772 . July 2008 . 18460466 . 10.1074/jbc.M800695200 . free .