Regulation of LEF-1/TCF transcription factors by Wnt and other signals

Current Opinion in Cell Biology

Volumn 11, Issue 2, 1999, Pages 233-240

  Eastman, Quinn ^a   Grosschedl, Rudolf ^a  

^a UNIVERSITY OF CALIFORNIA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BETA CATENIN; CYCLIC AMP BINDING PROTEIN; LYMPHOID ENHANCER FACTOR 1; SECRETORY PROTEIN; TRANSCRIPTION FACTOR;

PRIORITY JOURNAL; PROTEIN PROTEIN INTERACTION; REVIEW; SIGNAL TRANSDUCTION; TRANSACTIVATION; TRANSCRIPTION REGULATION;

EID: 0032941717     PISSN: 09550674     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0955-0674(99)80031-3     Document Type: Article

References (102)

1. Willert K., Nusse R. β-catenin: a key mediator of Wnt signaling. Curr Opin Genet Dev. 8:1998;95-102.
2. Dale T. Signal transduction by the Wnt family of ligands. Biochem J. 329:1998;209-223.
3. Cox R., Peifer M. Wingless signalling: the inconvenient complexities of life. Curr Biol. 8:1998;R140-R144.
4. Cadigan K., Nusse R. Wnt signaling: a common theme in animal development. Genes Dev. 11:1997;3286-3305.
5. Brown J., Moon R. Wnt signalling: why is everything so negative? Curr Opin Cell Biol. 10:1998;182-187.
6. Bienz M. TCF: transcriptional activator or repressor? Curr Opin Cell Biol. 10:1998;366-372.
7. van de Wetering M., Oosterwegel M., Dooijes D., Clevers H. Identification and cloning of TCF-1, a T lymphocyte-specific transcription factor containing a sequence-specific HMG box. EMBO J. 10:1991;123-132.
8. Travis A., Amsterdam A., Belanger C., Grosschedl R. LEF-1, a gene encoding a lymphoid-specific protein with an HMG domain, regulates T-cell receptor alpha enhancer function. Genes Dev. 5:1991;880-894.
9. Waterman M., Fischer W., Jones K. A thymus-specific member of the HMG protein family regulates the human T cell receptor Cα enhancer. Genes Dev. 5:1991;656-669.
10. Korinek V., Barker N., Willert K., Molenaar M., Roose J., Wagenaar G., Markman M., Lamers W., Destree O., Clevers H. Two members of the Tcf family implicated in Wnt/β-catenin signaling during embryogenesis in the mouse. Mol Cell Biol. 18:1998;1248-1256.
11. Giese K., Cox J., Grosschedl R. The HMG domain of lymphoid enhancer factor 1 bends DNA and facilitates assembly of functional nucleoprotein structures. Cell. 69:1992;185-195.
12. Love J., Li X., Case D., Giese K., Grosschedl R., Wright P. Structural basis for DNA bending by the architectural transcription factor LEF-1. Nature. 376:1995;791-795.
13. van de Wetering M., Castrop J., Korinek V., Clevers H. Extensive alternative splicing and dual promoter usage generate Tcf-1 protein isoforms with differential transcription control properties. Mol Cell Biol. 16:1996;745-775.
14. Hsu S., Galceran J., Grosschedl R. Modulation of transcriptional regulation by LEF-1 in response to Wnt-1 signaling and association with β-catenin. Mol Cell Biol. 18:1998;4807-4818. The data presented pinpoints the amino acids in LEF-1 necessary for a transcriptional response to Wnt-1 signaling and identifies two transcriptional activation domains in β-catenin. In these experiments, LEF-1 expression and Wnt signaling are both necessary to promote the nuclear localization of β-catenin. This study also compares the β-catenin-independent regulation of transcription by LEF-1 in association with ALY and the β-catenin-dependent regulation in response to Wnt signaling.
15. Giese K., Kingsley C., Kirshner J., Grosschedl R. Assembly of a TCRα enhancer complex is dependent on LEF-1 induced DNA bending and multiple protein-protein interactions. Genes Dev. 9:1995;995-1008.
16. Molenaar M., van der Wetering M., Oosterwegel M., Peterson-Maduro J., Godsave S., Korinek V., Roose J., Destree O., Clevers H. XTcf-3 transcription factor mediates β-catenin-axis formation in Xenopus embryos. Cell. 86:1996;391-399.
17. Behrens J., von Kries J., Kuhl M., Bruhn L., Wedlich D., Grosschedl R., Birchmeier W. Functional interaction of β-catenin with the transcription factor LEF-1. Nature. 382:1996;638-642.
18. Huber O., Korn R., McLaughlin J., Ohsugi M., Herrmann B., Kemler R. Nuclear localization of β-catenin by interaction with transcription factor LEF-1. Mech Dev. 59:1996;3-10.
19. ••] the authors describe the identification of the Drosophila TCF/Pangolin which is shown genetically to be downstream of Armadillo. By cooperation with Armadillo, dTCF can activate transcription from multimerized TCF binding sites; a truncated dTCF acts as a dominant-negative protein in transgenic flies.
20. Kengaku M., Capdevila J., Rodgriguez-Esteban C., De La Peña J., Johnson R., Belmonte J., Tabin C. Distinct Wnt pathways regulating AER formation and dorsoventral polarity in the chick limb bud. Science. 280:1998;1274-1277. Expression of Wnt3a, using retroviral vectors, initiates apical ectodermal ridge gene expression in the chick limb bud. Its effects can be mimicked by activated β-catenin and prevented by dominant-negative LEF-1 and evidence supports that transcription of LEF-1 itself is a Wnt target in this system. In contrast, the effects of Wnt7a in directing dorsoventral polarity are separate and not mediated by β-catenin or LEF-1.
21. Brannon M., Gomperts M., Sumoy L., Moon R., Kimelman D. A β-catenin/XTcf-3 complex binds to the siamois promoter to regulate dorsal axis specification in Xenopus. Genes Dev. 11:1997;2359-2370. Injection of Siamois promoter constructs into Xenopus embryos reveals a requirement for LEF-1/TCF binding sites for dorsal expression of Siamois. Interestingly, intact LEF-1/TCF binding sites are also necessary for ventral Siamois repression.
22. Dorsky R., Moon R., Raible D. Control of neural crest cell fate by the Wnt signaling pathway. Nature. 396:1998;370-373.
23. ••].
24. Oosterwegel M., van de Wetering M., Timmerman J., Kruisbeek A., Destree O., Meijlink F., Clevers H. Differential expression of the HMG box factors TCF-1 and LEF-1 during murine embryogenesis. Development. 118:1993;439-448.
25. Thomas K., Musci T., Neumann P., Capecchi M. Swaying is a mutant allele of the proto-oncogene Wnt-1. Cell. 67:1991;969-976.
26. Stark K., Vainio S., Vassileva G., McMahon A. Epithelial transformation of metanephric mesenchyme in the developing kidney regulated by Wnt-4. Nature. 372:1994;679-683.
27. Takada S., Stark K., Shea M., Vassileva G., McMahon J., McMahon A. Wnt3a regulates somite and tailbud formation in the mouse embryo. Genes Dev. 8:1994;174-189.
28. Monkley S., Delaney S., Pennisi D., Christiansen J., Wainwright B. Targeted disruption of the Wnt2 gene results in placentation defects. Development. 122:1996;3343-3353.
29. Parr B., McMahon A. Dorsalizing signal Wnt-7a required for normal polarity of D-V and A-P axes of mouse limb. Nature. 374:1995;350-353.
30. van Genderen C., Okamura R., Farinas I., Quo R., Parlow T., Bruhn L., Grosschedl R. Development of several organs that require inductive epithelial-mesenchymal interactions is impaired in LEF-1-deficient mice. Genes Dev. 8:1994;2691-2703.
31. Verbeek S., Izon D., Hofhuis F., Robanus-Maandag E., te Riele H., van de Wetering M., Oosterwegel M., Wilson A., MacDonald H., Clevers H. An HMG-box-containing T-cell factor required for thymocyte differentiation. Nature. 374:1995;70-74.
32. -/- mice. Genes Dev. 13:1999;709-717. Analysis of mice deficient in both LEF-1 and TCF-1 revealed a severe deficiency in paraxial mesoderm differentiation and the formation of ectopic neural tubes, a phenotype virtually identical to that found in Wnt3a-deficient mice. This observation provides strong evidence that these transcription factors mediate Wnt signaling in the mouse. In addition, mice lacking LEF-1 and TCF-1 show an arrest in limb bud development which is defined by the absence of the apical ectodermal ridge and a lack of Fgf8 expression.
33. Gat U., DasGupta R., Degenstein L., Fuchs E. De novo hair follicle morphogenesis and hair tumors in mice expressing a truncated β-catenin in skin. Cell. 95:1998;605-614. A truncated form of β-catenin, mimicking Wnt activation, is expressed in transgenic mice under the control of a keratin promoter. Well after the initiation of transgene expression, the mice display postnatal formation of hair follicles and eventually epithelial cysts and hair tumors. The de novo hair follicles show aberrant polarity and sonic hedgehog expression.
34. Korinek V., Barker N., Moerer P., van Donselaar E., Huls G., Peters P., Clevers H. Depletion of epithelial stem-cell compartments in the small intestine of mice lacking Tcf-4. Nat Genet. 19:1998;379-383.
35. -/- colon carcinoma. Science. 275:1997;1784-1787.
36. Morin P., Sparks A., Korinek V., Barker N., Clevers H., Vogelstein B., Kinzler K. Activation of β-catenin-Tcf signaling in colon cancer by mutations in β-catenin or APC. Science. 275:1997;1787-1790. Mutations in APC have been identified that stabilize β-catenin in colon cancer cell lines. In tumors in which APC is not mutated, β-catenin itself is found to be mutated, with the same result: the stabilization of β-catenin and its activation of Tcf-4-mediated transcription.
37. Laurent M., Blitz I., Hashimoto C., Rothbacher U., Cho K. The Xenopus homeobox gene twin mediates Wnt induction of goosecoid in establishment of Spemann's organizer. Development. 124:1997;4905-4916. Includes an analysis of the promoter of the Xenopus homeobox gene twin. LEF-1/TCF binding sites in the Xtwn promoter are critical for responsiveness to Wnt signalling. Cortical rotation redistributes cytoplasmic elements that stimulate Xtwn expression in a LEF-1/TCF dependent fashion.
38. Fan M., Gruning W., Walz G., Sokol S. Wnt signaling and transcriptional control of Siamois in Xenopus embryos. Proc Natl Acad Sci USA. 95:1998;5626-5631.
39. Riese J., Yu X., Munnerlyn A., Eresh S., Hsu S., Grosschedl R., Bienz M. LEF-1, a nuclear factor coordinating signaling inputs from wingless and decapentaplegic. Cell. 88:1997;777-787. A LEF-1/TCF binding site in the Ubx enhancer is shown to be the element necessary for a response to Wg in the Drosophila gut. LEF-1 overexpression mimics hyperactivation through Wg or Armadillo. The LEF-1/TCF binding site is next to a dpp response element (CRE-binding site). Importantly, LEF-1/dTcf activity in the gut is found here to depend upon and synergize with dpp signaling.
40. McKendry R., Hsu S., Harland R., Grosschedl R. LEF-1/TCF proteins mediate wnt-inducible transcription from the Xenopus nodal-related 3 promoter. Dev Biol. 192:1997;420-431. Analysis of Xnr-3 promoter constructs by injection into Xenopus embryos and in vitro binding studies. LEF-1/TCF binding sites in the Xnr-3 promoter are important for Wnt responsiveness and dorsal activation. A proximal binding site for homeodomain proteins is also necessary for optimal response to Wnts.
41. He T., Sparks A., Rago C., Hermeking H., Zawel L., da Costa L., Morin P., Vogelstein B., Kinzler K. Identification of c-MYC as a target of the APC pathway. Science. 281:1998;1509-1512. A differential screening approach is used to find genes whose expression in colon cancer cell lines is repressed by functional APC. This paper identifies the proto-oncogene, c-Myc, as a APC-repressed gene and identifies LEF-1/TCF binding sites in its promoter.
42. He X., Saint Jeannet J., Wang Y., Nathans J., Dawid I., Varmus H. A member of the Frizzled protein family mediating axis induction by Wnt5a. Science. 275:1997;1652-1654.
43. Bhanot P., Brink M., Samos C., Hsieh J., Wang Y., Macke J., Andrew D., Nathans J., Nusse R. A new member of the Frizzled family from Drosophila functions as a Wingless receptor. Nature. 382:1996;225-230.
44. Papkoff J., Rubinfeld B., Schryver B., Polakis P. Wnt-1 regulates free pools of catenins and stabilizes APC-catenin complexes. Mol Cell Biol. 16:1996;2128-2134.
45. Rubinfeld B., Albert I., Porfiri E., Fiol C., Munemitsu S., Polakis P. Binding of GSK3β to the APC - catenin complex and regulation of complex assembly. Science. 272:1996;1023-1026.
46. Zeng L., Fagotto F., Zhang T., Hsu W., Vasicek T., Perry W., Lee J., Tilghman S., Gumbiner B., Costantini F. The mouse fused locus encodes Axin, an inhibitor of the Wnt signaling pathway that regulates embryonic axis formation. Cell. 90:1997;181-192. This study identifies Axin as a negative regulator of Wnt signaling. The mouse fused locus, which in mutant form results in axis duplications, is shown to encode Axin. Injection of Axin mRNA into Xenopus embryos inhibits dorsal axis formation by interfering with signaling through the Wnt pathway.
47. Behrens J., Jerchow B., Wurtele M., Grimm J., Asbrand C., Wirtz R., Kühl M., Wedlich D., Birchmeier W. Functional interaction of an Axin homolog, Conductin, with β-catenin, APC, and GSK3β Science. 280:1998;596-599. The association of β-catenin, APC, and GSK3β is demonstrated by co-immunoprecipitation. This study also shows that fragments of APC that contain a Conductin-binding domain blocks degradation of β-catenin.
48. Hart M., de los Santos R., Albert I., Rubinfeld B., Polakis P. Downregulation of β-catenin by human Axin and its association with the APC tumor suppressor, β-catenin and GSK3β Curr Biol. 8:1998;573-581.
49. Ikeda S., Kishida S., Yamamoto H., Murai H., Koyama S., Kikuchi A. Axin, a negative regulator of the Wnt signaling pathway, forms a complex with GSK-3β and β-catenin and promotes GSK-3β-dependent phosphorylation of β-catenin. EMBO J. 17:1998;1371-1384. This paper makes it more plausible that GSK3β directly phosphorylates β-catenin. Axin seems to have been the missing link. Numerous immunoprecipitations and glutathione-S-transferase (GST)-pulldown experiments show that Axin acts as a scaffold protein, interacting with APC, GSK3β, and β-catenin, and stimulates GSK3β-mediated phosphorylation of β-catenin.
50. Kishida S., Yamamoto H., Ikeda S., Kishida M., Sakamoto I., Koyama S., Kikuchi A. Axin, a negative regulator of the Wnt signaling pathway, directly interacts with adenomatous polyposis coli and regulates the stabilization of β-catenin. J Biol Chem. 273:1998;10823-10826.
51. Sakanaka C., Weiss J., Williams L. Bridging of β-catenin and glycogen synthase kinase-3β by axin and inhibition of β-catenin-mediated transcription. Proc Natl Acad Sci USA. 95:1998;3020-3023.
52. Yamamoto H., Kishida S., Uochi T., Ikeda S., Koyama S., Asashima M., Kikuchi A. Axil, a member of the Axin family, interacts with both glycogen synthase kinase 3β and β-catenin and inhibits axis formation of Xenopus embryos. Mol Cell Biol. 18:1998;2867-2875.
53. Rubinfeld B., Robbins P., El-Gami M., Albert I., Porfiri E., Polakis P. Stabilization of β-catenin by genetic defects in melanoma cell lines. Science. 275:1997;1790-1792. This study shows that an upregulation of β-catenin in human melanomas is linked to mutations in either β-catenin or APC. In APC-deficient cells, expression of wild-type APC restored normal levels of β-catenin. By immunoprecipitations, constituative LEF-1-β-catenin complexes are detected in the melanoma cells. This study implies a role of β-catenin in cell proliferation.
54. Orford K., Crockett C., Jensen J., Weissman A., Beyers S. Serine phosphorylation-regulated ubiquitination and degradation of β-catenin. J Biol Chem. 272:1997;24735-24738.
55. Aberle H., Bauer A., Stappert J., Kispert A., Kemler R. β-catenin is a target for the ubiquitin-proteasome pathway. EMBO J. 16:1997;3797-3804.
56. Marikawa Y., Elinson R. β-TrCP is a negative regulator of Wnt/β-catenin signaling pathway and dorsal axis formation in Xenopus embryos. Mech Dev. 77:1998;75-80.
57. Jiang J., Struhl G. Regulation of the hedgehog and wingless signalling pathways by the F-box/WD40-repeat protein Slimb. Nature. 391:1998;493-496. This paper and [56] together begin to explore the machinery that targets β-catenin for degradation once it has been phosphorylated by the Axin/APC/GSK3β group of proteins. β-TrCP and Slimb are similar in sequence to Cdc4p, a protein in yeast that recognizes phosphorylated proteins and conveys them to ubiquitin-conjugating enzymes. The authors of [56] show that truncated TrCP can interfere with β-catenin degradation.
58. Papkoff J. Regulation of complexed and free catenin pools by distinct mechanisms: differential effects of Wnt-1 and v-Src. J Biol Chem. 272:1997;4536-4543.
59. Young C., Kitamura M., Hardy S., Kitajewski J. Wnt-1 induces growth, cytosolic β-catenin, and Tcf/Lef transcriptional activation in Rat-1 fibroblasts. Mol Cell Biol. 18:1998;2474-2485.
60. Yanagawa S., van Leeuwen F., Wodarz A., Klingensmith J., Nusse R. The dishevelled protein is modified by wingless signaling in Drosophila. Genes Dev. 9:1995;1087-1097.
61. Orsulic S., Peifer M. An in vivo structure-function study of armadillo, the β-catenin homologue, reveals both separate and overlapping regions of the protein required for cell adhesion and for wingless signaling. J Cell Biol. 134:1996;1283-1300.
62. Fagotto F., Gluck U., Gumbiner B. Nuclear localization signal-independent and importin/karyopherin-independent nuclear import of β-catenin. Curr Biol. 8:1998;181-190. This paper shows that β-catenin can bind directly to the nuclear pore machinery. Cytosolic factors, which may be a target for Wnt signaling, inhibit the GTP-dependent constitutive (in the absence of cytosol) nuclear import of β-catenin.
63. Cavallo R., Cox R., Moline M., Roose J., Polevoy G., Clevers H., Peifer M., Bejsovec A. Drosophila Tcf and Groucho interact to repress Wingless signalling activity. Nature. 395:1998;604-608. Genetic studies that further substantiate the idea that dTcf represses Wg target genes in the absence of Wg signaling. Groucho dosage affects the ability of dTcf to repress.
64. Roose J., Molenaar M., Peterson J., Hurenkamp J., Brantjes H., Moerer P., van der Wetering M., Destree O., Clevers H. The Xenopus Wnt effector XTcf3 interacts with Groucho-related transcriptional repressors. Nature. 395:1998;608-612. The two-hybrid system in yeast allows mapping of the Groucho-binding domain in TCF proteins. Experiments in Xenopus embryos and in mammalian cells show that Groucho-Tcf binding represses the effects of Wnt signaling and transcription from a multimerized LEF-1/TCF reporter.
65. Fisher A., Caudy M. Groucho proteins: transcriptional corepressors for specific subsets of DNA-binding transcription factors in vertebrates and invertebrates. Genes Dev. 12:1998;1931-1940.
66. ••] this was not demonstrated. The discrepancy may be explained by postulating different LEF-1 binding affinities among the different Groucho/TLE proteins.
67. Palaparti A., Baratz A., Stifani S. The Groucho/transducin-like enhancer of split transcriptional repressors interact with the genetically defined amino-terminal silencing domain of histone H3. J Biol Chem. 272:1997;26604-26610.
68. Shikama N., Lyon J., La Thangue N. The p300/CBP family: integrating signals with transcription factors and chromatin. Trends Cell Bio. 7:1997;230-237.
69. Waltzer L., Bienz M. Drosophila CBP represses the transcription factor TCF to antagonize Wingless signalling. Nature. 395:1998;521-525. Here, CBP mutations are shown to derepress Wg target genes. dCBP binds to dTcf and acetylates its β-catenin-binding domain. Acetylation by CBP is shown to be a negative influence on dTcf in vivo.
70. Munshi N., Merika M., Yie J., Senger K., Chen G., Thanos D. Acetylation of HMG I(Y) by CBP turns off IFNβ expression by disrupting the enhanceosome. Mol Cell. 2:1998;457-467.
71. Moon R., Kimelman D. From cortical rotation to organizer gene expression: toward a molecular explanation of axis specification in Xenopus. Bioessays. 20:1998;536-545. This review takes a close look at how cortical rotation leads to axis formation in Xenopus embryos. It describes the evidence for Wnt-independent but β-catenin mediated control of crucial organizer genes like Siamois and twin.
72. Cui Y., Brown J., Moon R., Christian J. Xwnt8b: a maternally expressed Xenopus Wnt gene with a potential role in establishing the dorso-ventral axis. Development. 121:1995;2177-2186.
73. Sokol S. Analysis of Dishevelled signaling pathways during Xenopus development. Curr Biol. 6:1996;1456-1467.
74. Hoppler S., Brown J., Moon R. Expression of a dominant negative Wnt blocks induction of MyoD in Xenopus embryos. Genes Dev. 10:1996;2805-2817.
75. •]).
76. Novak A., Hsu S., Leung-Hagesteijn C., Radeva G., Papkoff J., Montesano R., Roskelley C., Grosschedl R., Dedhar S. Cell adhesion and the integrin-linked kinase regulate the LEF-1 and β-catenin signaling pathways. Proc Natl Acad Sci USA. 95:1998;4374-4379. Overexpression of ILK in an epithelial cell line leads to the stabilization of β-catenin and activation of a LEF-1/TCF reporter. In addition, both ILK overexpression and the loss of cell adhesion upregulate LEF-1 protein expression. Both sides of the β-catenin/LEF-1 interaction are thus linked to responses to changes in cell adhesion. See also (other ILK articles).
77. Wu C., Keightley S., Leung-Hagesteijn C., Radeva G., Coppolino M., Goicoechea S., McDonald J., Dedhar S. Integrin-linked protein kinase regulates fibronectin matrix assembly, E-cadherin expression, and tumorigenicity. J Biol Chem. 273:1998;528-536.
78. Radeva G., Petrocelli T., Behrend E., Leung-Hagesteijn C., Filmus J., Slingerland J., Dedhar S. Overexpression of the integrin-linked kinase promotes anchorage-independent cell cycle progression. J Biol Chem. 272:1997;13937-13944.
79. Hannigan G., Leung-Hagesteijn C., Fitz-Gibbon L., Coppolino M., Radeva G., Filmus J., Bell J., Dedhar S. Regulation of cell adhesion and anchorage-dependent growth by a new β1-integrin-linked protein kinase. Nature. 379:1996;91-96.
80. Delcommenne M., Tan C., Gray V., Rue L., Woodgett J., Dedhar S. Phosphoinositide-3-OH kinase-dependent regulation of glycogen synthase kinase and protein kinase B/AKT by the integrin-linked kinase. Proc Natl Acad Sci USA. 95:1998;11211-11216. This paper describes ILK as an upstream regulator of both GSK3β and PKB. Signaling by both insulin and fibronectin are proposed to regulate ILK, in a PI3 kinase dependent fashion.
81. Eldar-Finkelman H., Seger R., Vandenheede J., Krebs E. Inactivation of glycogen synthase kinase-3 by epidermal growth factor is mediated by mitogen-activated protein kinase/p90 ribosomal protein S6 kinase signaling pathway in NIH/3T3 cells. J Biol Chem. 270:1995;987-990.
82. Cross D., Alessi D., Cohen P., Andjelkovich M., Hemmings B. Inhibition of glycogen synthase kinase-3 by insulin mediated by protein kinase B. Nature. 378:1995;785-789.
83. Papkoff J., Aikawa M. WNT-1 and HGF regulate GSK3β activity and β-catenin signaling in mammary epithelial cells. Biochem Biophys Res Commun. 247:1998;851-858. This paper shows that both Wnt-1, as expected, and HGF, which acts through the receptor tyrosine kinase Met, can increase β-catenin stability and LEF-1/TCF reporter activation. The mechanism by which Met regulates GSK3β activity and β-catenin stability remains to be determined.
84. Fagotto F., Funayama N., Gluck U., Gumbiner B. Binding to cadherins antagonizes the signaling activity of β-catenin during axis formation in Xenopus. J Cell Biol. 132:1996;1105-1114.
85. Sanson B., White P., Vincent J. Uncoupling cadherin-based adhesion from wingless signalling in Drosophila. Nature. 383:1996;627-630.
86. Heasman J., Crawford A., Goldstone K., Garner-Hamrick P., Gumbiner B., McCrea P., Kintner C., Noro Y., Wylie C. Overexpression of cadherins and underexpression of β-catenin inhibit dorsal mesoderm induction in early Xenopus embryos. Cell. 79:1994;791-803.
87. Cox R., Kirkpatrick C., Peifer M. Armadillo is required for adherens junction assembly, cell polarity, and morphogenesis during Drosophila embryogenesis. J Cell Biol. 134:1996;133-148.
88. Rosato R., Veltmaat J., Groffen J., Heisterkamp N. Involvement of the tyrosine kinase Fer in cell adhesion. Mol Cell Biol. 18:1998;5762-5770. The nonreceptor tyrosine kinase Fer interacts with β-catenin. Overexpression of Fer interferes with cell adhesion, dissociating α- and β-catenin from E-cadherin.
89. Hazan R., Norton L. The epidermal growth factor receptor modulates the interaction of E-cadherin with the actin cytoskeleton. J Biol Chem. 273:1998;9078-9084. In the cell line studied, which does not express α-catenin, epidermal growth factor signaling does not affect the E-cadherin-β-catenin interaction, but instead dissociates vinculin from the catenin-cadherin complex.
90. Murayama M., Tanaka S., Palacino J., Murayama O., Honda T., Sun X., Yasutake K., Nihonmatsu N., Wolozin B., Takashima A. Direct association of presenilin-1 with β-catenin. FEBS Lett. 433:1998;73-77.
91. Yu G., Chen F., Levesque G., Nishimura M., Zhang D., Levesque L., Rogaeva E., Xu D., Liang Y., Duthie M.et al. The presenilin 1 protein is a component of a high molecular weight intracellular complex that contains β-catenin. J Biol Chem. 273:1998;16470-16475. These two papers show that β-catenin associates with proteolytically processed PS1 protein fragments in a 250 kDa complex. The components of this complex (1:1:1) do not add up to 250 kDa - other components need to be identified and the relationship with cytoplasmic or cadherin-bound β-catenin needs to be clarified.
92. Zhang Z., Hartmann H., Do V., Abramowski D., Sturchler-Pierrat C., Staufenbiel M., Sommer B., van de Wetering M., Clevers H., Saftig P.et al. Destabilization of β-catenin by mutations in presenilin-1 potentiates neuronal apoptosis. Nature. 395:1998;698-702. This paper makes two links: one between mutations in presenilin and a decrease in β-catenin stability in neurons and the other between lowered β-catenin levels and susceptibility of neurons to apoptosis. Because the effect of presenilin mutations can be mimicked by a dominant negative TCF, the existence of transcriptional targets for LEF-1/TCF that mediate cell survival is implied.
93. Levitan D., Greenwald I. Effects of SEL-12 presenilin on LIN-12 localization and function in C. elegans. Development. 125:1998;3599-3606. Mutations in the presenilin homolog in C. elegans, SEL-12, reduce the levels of LIN-12, a Notch homologue, at the plasma membrane. SEL-12 is proposed to specifically enhance the trafficking or proteolytic processing of LIN-12.
94. Okamura R.M., Sigvardsson M., Galceran J., Verbeek S., Clevers H., Grosschedl R. Redundant regulation of T cell differentiation and TCR α expression by the transcription factors LEF-1 and TCF-1. Immunity. 8:1998;11-20.
95. Bruhn L., Munnerlyn A., Grosschedl R. ALY, a context-dependent coactivator of LEF-1 and AML-1, is required for TCRα enhancer function. Genes Dev. 11:1997;640-653. Identification and characterization of ALY as a co-activator of LEF-1, which interacts with the context-dependent activation domains of LEF-1 and AML-1. Transcription factors occupy adjacent sites in the TCRα enhancer.
96. Prieve M., Guttridge K., Munguia J., Waterman M. Differential importin-α recognition and nuclear transport by nuclear localization signals within the high-mobility-group DNA binding domains of lymphoid enhancer factor 1 and T-cell factor 1. Mol Cell Biol. 18:1998;4819-4832.
97. Slusarski D., Corces V., Moon R. Interaction of Wnt and a Frizzled homologue triggers G-protein-linked phosphatidylinositol signalling. Nature. 390:1997;410-413.
98. Moon R., Campbell R., Christian J., McGrew L., Shih J., Fraser S. Xwnt-5A: a maternal Wnt that affects morphogenetic movements after overexpression in embryos of Xenopus laevis. Development. 119:1993;97-111.
99. Axelrod J., Miller J., Shulman J., Moon R., Periimon N. Differential recruitment of Dishevelled provides signaling specificity in the planar cell polarity and Wingless signaling pathways. Genes Dev. 12:1998;2610-2622.
100. Boutros M., Paricio N., Strutt D., Mlodzik M. Dishevelled activates JNK and discriminates between JNK pathways in planar polarity and wingless signalling. Cell. 94:1998;109-118. The domains of the Drosophila protein Dishevelled that are responsible for cell polarity and Wg signaling are distinguished. Cell polarity signaling depends upon recruitment of Dsh to the plasma membrane, while Wg signaling does not. Boutros et al. show that cell polarity signaling by Dsh involves the activation of small GTPases and JNK kinases.
101. Rocheleau C., Downs W., Lin R., Wittmann C., Bei Y., Cha Y., Ali M., Priess J., Mello C. Wnt signaling and an APC-Related gene specify endoderm in early C. elegans embryos. Cell. 90:1997;707-716. In C. elegans, signaling from P2 to the EMS blastomere affects both endoderm specification and cell polarity. Downstream of the initial signaling events mediated by a Wnt-Fz pair (mom-2 and mom-5), a pathway involving homologs of β-catenin (wrm-1), APC (apr-1), and LEF-1/TCF (pop-1) influences endoderm formation. The pathway influencing cell polarity is also downstream of mom-2 and mom-5 but does not make use of wrm-1 or pop-1.
102. Kratochwil K., Dull M., Farinas I., Galceran J., Grosschedl R. Lef1 expression is activated by BMP-4 and regulates inductive tissue interactions in tooth and hair development. Genes Dev. 10:1996;1382-1394.