The Synthetic Multivulva Genes Prevent Ras Pathway Activation by Tightly Repressing Global Ectopic Expression of EGF

English version České info

The Caenorhabditis elegans class A and B synthetic multivulva (synMuv) genes redundantly antagonize an EGF/Ras pathway to prevent ectopic vulval induction. We identify a class A synMuv mutation in the promoter of the lin-3 EGF gene, establishing that lin-3 is the key biological target of the class A synMuv genes in vulval development and that the repressive activities of the class A and B synMuv pathways are integrated at the level of lin-3 expression. Using FISH with single mRNA molecule resolution, we find that lin-3 EGF expression is tightly restricted to only a few tissues in wild-type animals, including the germline. In synMuv double mutants, lin-3 EGF is ectopically expressed at low levels throughout the animal. Our findings reveal that the widespread ectopic expression of a growth factor mRNA at concentrations much lower than that in the normal domain of expression can abnormally activate the Ras pathway and alter cell fates. These results suggest hypotheses for the mechanistic basis of the functional redundancy between the tumor-suppressor-like class A and B synMuv genes: the class A synMuv genes either directly or indirectly specifically repress ectopic lin-3 expression; while the class B synMuv genes might function similarly, but alternatively might act to repress lin-3 as a consequence of their role in preventing cells from adopting a germline-like fate. Analogous genes in mammals might function as tumor suppressors by preventing broad ectopic expression of EGF-like ligands.

Vyšlo v časopise: The Synthetic Multivulva Genes Prevent Ras Pathway Activation by Tightly Repressing Global Ectopic Expression of EGF. PLoS Genet 7(12): e32767. doi:10.1371/journal.pgen.1002418
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pgen.1002418

Souhrn

Zdroje

1. NormannoNDe LucaABiancoCStrizziLMancinoM 2006 Epidermal growth factor receptor (EGFR) signaling in cancer. Gene 366 2 16

2. MassagueJ 1990 Transforming growth factor-alpha. A model for membrane-anchored growth factors. J Biol Chem 265 21393 21396

3. YotsumotoFYagiHSuzukiSOOkiETsujiokaH 2008 Validation of HB-EGF and amphiregulin as targets for human cancer therapy. Biochem Biophys Res Commun 365 555 561

4. JhappanCStahleCHarkinsRNFaustoNSmithGH 1990 TGF alpha overexpression in transgenic mice induces liver neoplasia and abnormal development of the mammary gland and pancreas. Cell 61 1137 1146

5. SandgrenEPLuettekeNCPalmiterRDBrinsterRLLeeDC 1990 Overexpression of TGF alpha in transgenic mice: induction of epithelial hyperplasia, pancreatic metaplasia, and carcinoma of the breast. Cell 61 1121 1135

6. DownwardJ 2003 Targeting RAS signalling pathways in cancer therapy. Nat Rev Cancer 3 11 22

7. AroianRVKogaMMendelJEOhshimaYSternbergPW 1990 The let-23 gene necessary for Caenorhabditis elegans vulval induction encodes a tyrosine kinase of the EGF receptor subfamily. Nature 348 693 699

8. BeitelGJClarkSGHorvitzHR 1990 Caenorhabditis elegans ras gene let-60 acts as a switch in the pathway of vulval induction. Nature 348 503 509

9. HanMSternbergPW 1990 let-60, a gene that specifies cell fates during C. elegans vulval induction, encodes a ras protein. Cell 63 921 931

10. HillRJSternbergPW 1992 The gene lin-3 encodes an inductive signal for vulval development in C. elegans. Nature 358 470 476

11. SternbergPWHorvitzHR 1986 Pattern formation during vulval development in C. elegans. Cell 44 761 772

12. KimbleJ 1981 Alterations in cell lineage following laser ablation of cells in the somatic gonad of Caenorhabditis elegans. Dev Biol 87 286 300

13. KatzWSLesaGMYannoukakosDClandininTRSchlessingerJ 1996 A point mutation in the extracellular domain activates LET-23, the Caenorhabditis elegans epidermal growth factor receptor homolog. Mol Cell Biol 16 529 537

14. FergusonELHorvitzHR 1989 The multivulva phenotype of certain Caenorhabditis elegans mutants results from defects in two functionally redundant pathways. Genetics 123 109 121

15. AndersenECSafferAMHorvitzHR 2008 Multiple levels of redundant processes inhibit Caenorhabditis elegans vulval cell fates. Genetics 179 2001 2012

16. LuXHorvitzHR 1998 lin-35 and lin-53, two genes that antagonize a C. elegans Ras pathway, encode proteins similar to Rb and its binding protein RbAp48. Cell 95 981 991

17. CeolCJHorvitzHR 2001 dpl-1 DP and efl-1 E2F act with lin-35 Rb to antagonize Ras signaling in C. elegans vulval development. Mol Cell 7 461 473

18. SolariFAhringerJ 2000 NURD-complex genes antagonise Ras-induced vulval development in Caenorhabditis elegans. Curr Biol 10 223 226

19. UnhavaithayaYShinTHMiliarasNLeeJOyamaT 2002 MEP-1 and a homolog of the NURD complex component Mi-2 act together to maintain germline-soma distinctions in C. elegans. Cell 111 991 1002

20. AndersenECHorvitzHR 2007 Two C. elegans histone methyltransferases repress lin-3 EGF transcription to inhibit vulval development. Development 134 2991 2999

21. PoulinGDongYFraserAGHopperNAAhringerJ 2005 Chromatin regulation and sumoylation in the inhibition of Ras-induced vulval development in Caenorhabditis elegans. Embo J 24 2613 2623

22. CouteauFGuerryFMullerFPalladinoF 2002 A heterochromatin protein 1 homologue in Caenorhabditis elegans acts in germline and vulval development. EMBO Rep 3 235 241

23. HuangLSTzouPSternbergPW 1994 The lin-15 locus encodes two negative regulators of Caenorhabditis elegans vulval development. Mol Biol Cell 5 395 411

24. ClarkSGLuXHorvitzHR 1994 The Caenorhabditis elegans locus lin-15, a negative regulator of a tyrosine kinase signaling pathway, encodes two different proteins. Genetics 137 987 997

25. DavisonEMSafferAMHuangLSDemodenaJSternbergPW 2011 The LIN-15A and LIN-56 Transcriptional Regulators Interact to Negatively Regulate EGF/Ras Signaling in Caenorhabditis elegans Vulval Cell-Fate Determination. Genetics 187 803 815

26. DavisonEMHarrisonMMWalhoutAJVidalMHorvitzHR 2005 lin-8, which antagonizes Caenorhabditis elegans Ras-mediated vulval induction, encodes a novel nuclear protein that interacts with the LIN-35 Rb protein. Genetics 171 1017 1031

27. CuiMChenJMyersTRHwangBJSternbergPW 2006 SynMuv genes redundantly inhibit lin-3/EGF expression to prevent inappropriate vulval induction in C. elegans. Dev Cell 10 667 672

28. FergusonELSternbergPWHorvitzHR 1987 A genetic pathway for the specification of the vulval cell lineages of Caenorhabditis elegans. Nature 326 259 267

29. HedgecockEMHermanRK 1995 The ncl-1 gene and genetic mosaics of Caenorhabditis elegans. Genetics 141 989 1006

30. HermanRKHedgecockEM 1990 Limitation of the size of the vulval primordium of Caenorhabditis elegans by lin-15 expression in surrounding hypodermis. Nature 348 169 171

31. MyersTRGreenwaldI 2005 lin-35 Rb acts in the major hypodermis to oppose ras-mediated vulval induction in C. elegans. Dev Cell 8 117 123

32. SchottSRamosFCousthamVPalladinoF 2009 HPL-2/HP1 prevents inappropriate vulval induction in Caenorhabditis elegans by acting in both HYP7 and vulval precursor cells. Genetics 181 797 801

33. CeolCJHorvitzHR 2004 A new class of C. elegans synMuv genes implicates a Tip60/NuA4-like HAT complex as a negative regulator of Ras signaling. Dev Cell 6 563 576

34. SiegfriedKRKiddAR3rdChesneyMAKimbleJ 2004 The sys-1 and sys-3 genes cooperate with Wnt signaling to establish the proximal-distal axis of the Caenorhabditis elegans gonad. Genetics 166 171 186

35. HanMAroianRVSternbergPW 1990 The let-60 locus controls the switch between vulval and nonvulval cell fates in Caenorhabditis elegans. Genetics 126 899 913

36. FergusonELHorvitzHR 1985 Identification and characterization of 22 genes that affect the vulval cell lineages of the nematode Caenorhabditis elegans. Genetics 110 17 72

37. LiuJTzouPHillRJSternbergPW 1999 Structural requirements for the tissue-specific and tissue-general functions of the Caenorhabditis elegans epidermal growth factor LIN-3. Genetics 153 1257 1269

38. KatzWSHillRJClandininTRSternbergPW 1995 Different levels of the C. elegans growth factor LIN-3 promote distinct vulval precursor fates. Cell 82 297 307

39. ChangCNewmanAPSternbergPW 1999 Reciprocal EGF signaling back to the uterus from the induced C. elegans vulva coordinates morphogenesis of epithelia. Curr Biol 9 237 246

40. HwangBJSternbergPW 2004 A cell-specific enhancer that specifies lin-3 expression in the C. elegans anchor cell for vulval development. Development 131 143 151

41. HsiehJLiuJKostasSAChangCSternbergPW 1999 The RING finger/B-box factor TAM-1 and a retinoblastoma-like protein LIN-35 modulate context-dependent gene silencing in Caenorhabditis elegans. Genes Dev 13 2958 2970

42. RajAvan den BogaardPRifkinSAvan OudenaardenATyagiS 2008 Imaging individual mRNA molecules using multiple singly labeled probes. Nat Methods 5 877 879

43. ThompsonBELamontLBKimbleJ 2006 Germ-line induction of the Caenorhabditis elegans vulva. Proc Natl Acad Sci U S A 103 620 625

44. WangDKennedySConteDJrKimJKGabelHW 2005 Somatic misexpression of germline P granules and enhanced RNA interference in retinoblastoma pathway mutants. Nature 436 593 597

45. PetrellaLNWangWSpikeCARechtsteinerAReinkeV 2011 synMuv B proteins antagonize germline fate in the intestine and ensure C. elegans survival. Development 138 1069 1079

46. KellyWGXuSMontgomeryMKFireA 1997 Distinct requirements for somatic and germline expression of a generally expressed Caernorhabditis elegans gene. Genetics 146 227 238

47. JiangLISternbergPW 1998 Interactions of EGF, Wnt and HOM-C genes specify the P12 neuroectoblast fate in C. elegans. Development 125 2337 2347

48. ThomasJHSternMJHorvitzHR 1990 Cell interactions coordinate the development of the C. elegans egg-laying system. Cell 62 1041 1052

49. HuMPolyakK 2008 Microenvironmental regulation of cancer development. Curr Opin Genet Dev 18 27 34

50. BrennerS 1974 The genetics of Caenorhabditis elegans. Genetics 77 71 94

51. WicksSRYehRTGishWRWaterstonRHPlasterkRH 2001 Rapid gene mapping in Caenorhabditis elegans using a high density polymorphism map. Nat Genet 28 160 164

52. SchmittgenTDLivakKJ 2008 Analyzing real-time PCR data by the comparative C(T) method. Nat Protoc 3 1101 1108