title: Ceramide synthases 2, 5, and 6 confer distinct roles in radiation-induced apoptosis in HeLa cells.
abstract: The role of ceramide neo-genesis in cellular stress response signaling is gaining increasing attention with recent progress in elucidating the novel roles and biochemical properties of the ceramide synthase (CerS) enzymes. Selective tissue and subcellular distribution of the six mammalian CerS isoforms, combined with distinct fatty acyl chain length substrate preferences, implicate differential functions of specific ceramide species in cellular signaling. We report here that ionizing radiation (IR) induces de novo synthesis of ceramide to influence HeLa cell apoptosis by specifically activating CerS isoforms 2, 5, and 6 that generate opposing anti- and pro-apoptotic ceramides in mitochondrial membranes. Overexpression of CerS2 resulted in partial protection from IR-induced apoptosis whereas overexpression of CerS5 increased apoptosis in HeLa cells. Knockdown studies determined that CerS2 is responsible for all observable IR-induced C(24:0) CerS activity, and while CerS5 and CerS6 each confer approximately 50% of the C(16:0) CerS baseline synthetic activity, both are required for IR-induced activity. Additionally, co-immunoprecipitation studies suggest that CerS2, 5, and 6 might exist as heterocomplexes in HeLa cells, providing further insight into the regulation of CerS proteins. These data add to the growing body of evidence demonstrating interplay among the CerS proteins in a stress stimulus-, cell type- and subcellular compartment-specific manner.
authors.affiliation: Laboratory of Signal Transduction, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
authors.forename: Judith
authors.initials: J
authors.lastname: Mesicek
authors.forename: Hyunmi
authors.initials: H
authors.lastname: Lee
authors.forename: Taya
authors.initials: T
authors.lastname: Feldman
authors.forename: Xuejun
authors.initials: X
authors.lastname: Jiang
authors.forename: Anastasia
authors.initials: A
authors.lastname: Skobeleva
authors.forename: Evgeny V
authors.initials: EV
authors.lastname: Berdyshev
authors.forename: Adriana
authors.initials: A
authors.lastname: Haimovitz-Friedman
authors.forename: Zvi
authors.initials: Z
authors.lastname: Fuks
authors.forename: Richard
authors.initials: R
authors.lastname: Kolesnick
mesh_terms: D000214:Acyl Coenzyme A / Q000378:metabolism; D017209:Apoptosis; D002518:Ceramides / Q000096:biosynthesis; D006367:HeLa Cells; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism* / Q000502:physiology; D008928:Mitochondria / Q000378:metabolism / Q000528:radiation effects; D010171:Palmitoyl Coenzyme A / Q000378:metabolism; D011839:Radiation, Ionizing; D051049:Sphingosine N-Acyltransferase / Q000378:metabolism* / Q000502:physiology; D025521:Tumor Suppressor Proteins / Q000378:metabolism* / Q000502:physiology
chemical_list: D000214:Acyl Coenzyme A; D002518:Ceramides; D007527:Isoenzymes; D008565:Membrane Proteins; D025521:Tumor Suppressor Proteins; D010171:Palmitoyl Coenzyme A; C018582:lignoceroyl-coenzyme A; C438311:CERS2 protein, human; C505722:CERS5 protein, human; C506123:CERS6 protein, human; D051049:Sphingosine N-Acyltransferase
references.citation: J Immunol. 2004 Oct 1;173(7):4425-32
references.pmid: 15383573
references.citation: Biochim Biophys Acta. 2002 Dec 30;1585(2-3):114-25
references.pmid: 12531544
references.citation: J Biol Chem. 2002 Nov 8;277(45):42572-8
references.pmid: 12200446
references.citation: Biochem J. 2004 Sep 1;382(Pt 2):527-33
references.pmid: 15144238
references.citation: Methods Enzymol. 2000;322:373-8
references.pmid: 10914031
references.citation: Science. 1993 Mar 19;259(5102):1769-71
references.pmid: 8456305
references.citation: J Biol Chem. 2009 Feb 27;284(9):5467-77
references.pmid: 19119142
references.citation: Proc Natl Acad Sci U S A. 2004 Dec 28;101(52):18030-5
references.pmid: 15596714
references.citation: J Biol Chem. 2005 Jul 15;280(28):26425-34
references.pmid: 15849201
references.citation: J Biol Chem. 2003 Oct 31;278(44):43452-9
references.pmid: 12912983
references.citation: J Biol Chem. 2005 Jun 17;280(24):23262-72
references.pmid: 15837784
references.citation: Science. 2008 Oct 3;322(5898):110-5
references.pmid: 18832646
references.citation: J Biol Chem. 2001 Jun 29;276(26):23954-61
references.pmid: 11287428
references.citation: J Biol Chem. 2004 Oct 22;279(43):44311-9
references.pmid: 15317812
references.citation: J Pharmacol Exp Ther. 2008 Oct;327(1):45-57
references.pmid: 18612046
references.citation: Trends Cell Biol. 2009 Feb;19(2):81-8
references.pmid: 19144519
references.citation: J Biol Chem. 2008 Feb 29;283(9):5677-84
references.pmid: 18165233
references.citation: J Biol Chem. 2009 Mar 13;284(11):6946-54
references.pmid: 19121999
references.citation: Cell. 1995 Aug 11;82(3):405-14
references.pmid: 7634330
references.citation: J Biol Chem. 1990 May 5;265(13):7248-56
references.pmid: 2332429
references.citation: Science. 2003 May 16;300(5622):1155-9
references.pmid: 12750523
references.citation: J Pharmacol Exp Ther. 2008 Feb;324(2):548-57
references.pmid: 18042827
references.citation: Curr Opin Cell Biol. 2004 Dec;16(6):647-52
references.pmid: 15530776
references.citation: J Lipid Res. 2008 Mar;49(3):625-34
references.pmid: 18073406
references.citation: Trends Cell Biol. 1996 Jun;6(6):218-23
references.pmid: 15157459
references.citation: Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2005 Sep;100(3):321-9
references.pmid: 16122660
references.citation: J Biol Chem. 2005 Nov 18;280(46):38271-5
references.pmid: 16172118
references.citation: Rapid Commun Mass Spectrom. 2004;18(14):1569-74
references.pmid: 15282781
references.citation: Science. 1995 Mar 10;267(5203):1506-10
references.pmid: 7878471
references.citation: Cell Signal. 2006 Oct;18(10):1779-92
references.pmid: 16529909
references.citation: Rapid Commun Mass Spectrom. 2003;17(11):1203-11
references.pmid: 12772277
references.citation: J Proteome Res. 2009 Oct;8(10):4810-22
references.pmid: 19705920
references.citation: Nat Rev Mol Cell Biol. 2008 Feb;9(2):139-50
references.pmid: 18216770
references.citation: Nat Med. 2005 May;11(5):491-8
references.pmid: 15852018
references.citation: J Biol Chem. 1999 Jun 18;274(25):17908-17
references.pmid: 10364237
references.citation: FASEB J. 2010 Jan;24(1):296-308
references.pmid: 19723703
references.citation: J Biol Chem. 2007 Aug 31;282(35):25940-9
references.pmid: 17609208
references.citation: Int J Biochem Cell Biol. 2009 Oct;41(10):1884-9
references.pmid: 19439192
references.citation: J Lipid Res. 2008 Nov;49(11):2356-64
references.pmid: 18541923
references.citation: J Biol Chem. 2010 Apr 2;285(14):10911-23
references.pmid: 20110366
references.citation: J Biol Chem. 2010 Apr 2;285(14):10902-10
references.pmid: 20110363
references.citation: EMBO J. 2005 Feb 23;24(4):730-41
references.pmid: 15692566
references.citation: Biochem J. 2006 Sep 15;398(3):531-8
references.pmid: 16753040
references.citation: J Biol Chem. 1992 Jun 5;267(16):11144-8
references.pmid: 1317856
references.citation: Biochem Soc Trans. 1997 May;25(2):557-61
references.pmid: 9191155
references.citation: J Biol Chem. 2002 Sep 20;277(38):35642-9
references.pmid: 12105227
references.citation: Oncogene. 2009 Feb 26;28(8):1132-41
references.pmid: 19137010
references.citation: Biochim Biophys Acta. 2006 Dec;1758(12):2027-36
references.pmid: 17161984
references.citation: Biochem J. 2005 Aug 15;390(Pt 1):263-71
references.pmid: 15823095
references.citation: Biochem J. 1993 Mar 15;290 ( Pt 3):751-7
references.pmid: 8457204
references.citation: Nat Med. 2005 May;11(5):484-90
references.pmid: 15864314
references.citation: Science. 2004 Jul 30;305(5684):626-9
references.pmid: 15286356
references.citation: FEBS Lett. 2007 Nov 13;581(27):5289-94
references.pmid: 17977534
references.citation: Biochem J. 2009 Nov 11;424(2):273-83
references.pmid: 19728861
references.citation: Genes Dev. 1999 Aug 1;13(15):1899-911
references.pmid: 10444588
references.citation: J Pharmacol Exp Ther. 2003 Apr;305(1):232-9
references.pmid: 12649374