ライフサイエンスコーパス: MEKK2

1 en-activated protein kinase kinase kinase 2 (MEKK2).

2 the human counterpart of the reported murine MEKK2.

3 not bind MEKK3, which is closely related to MEKK2.

4 -immunoprecipitated and PRK2 is activated by MEKK2.

5 BMK1)/ERK5 pathway, as a binding partner for MEKK2.

6 was performed to identify proteins that bind MEKK2.

7 sely related kinase PRK1, which did not bind MEKK2.

8 ll adapter protein, as a binding partner for MEKK2.

9 ylation and activation of a key MAP3 kinase, MEKK2.

10 lioblastoma, including PTEN, RB1, and MAP3K2/MEKK2.

11 LR) protein SUMM2 and the MAPK kinase kinase MEKK2.

12 at it heterodimerizes with the PB1 domain of MEKK2.

13 tors, Smads, transcription factors, RhoA and MEKK2.

14 promotes the ubiquitination and turnover of MEKK2.

15 nase 5, and AP-1 reporter gene activation by MEKK2.

16 s than the phosphorylated and, hence, active MEKK2.

17 complex with inactive and nonphosphorylated MEKK2.

18 Kinase-inactive MEKK1, but not MEKK2, 3 or 4, strongly inhibited EGF-stimulated ERK act

19 MEKK1, but not MEKK2, -3 or -4, is a caspase-3 substrate that when clea

20 tudy reveals a novel molecular mechanism for MEKK2/3 activation by the TLR and cellular stress pathwa

21 this serine to an alanine severely impaired MEKK2/3 activation.

22 We generated an anti-p-MEKK2/3 antibody and used this antibody to demonstrate t

23 at LSS induces Klf2 via activation of both a MEKK2/3-MEK5-ERK5 kinase module and mitochondrial metabo

24 1 in the ERK5 MAP kinase pathway upstream of MEKK2/3.

25 We show that MEK kinase 2 (MEKK2), a MAPK kinase kinase (MAP3K) that regulates the

26 ing adaptor protein that binds MEK kinase 2 (MEKK2), a mitogen-activated protein kinase (MAPK) kinase

27 d activates Rap1, a small GTPase, as well as MEKK2, a MEK5 kinase.

28 Activation of MEKK2, a mitogen-activated protein (MAP) kinase kinase k

29 Importantly, disrupted expression of MEKK2, a related MAPK kinase kinase, had no effect on uP

30 ssion of constitutively active MPK4 restored MEKK2 abundance to wild-type levels in mekk1 mutant plan

31 Compared with MEKK3, MEKK2 activated BMK1/ERK5 to a greater extent, which mig

32 Similarly, purified recombinant MEKK2 activated PRK2 in vitro.

33 We describe an alternative pathway by which MEKK2 activates MEK5 and big MAP kinase1/extracellular s

34 n the vascular and immune systems the MAP3K, MEKK2, activates different substrates, but the mechanism

35 In particular, Mip1 prevented MEKK2 activation by blocking MEKK2 dimer formation, whic

36 MEKK2 activation of PRK2 is independent of MEKK2 regulat

37 MEKK2 activation of PRK2 results in a bifurcation of sig

38 In this study, we demonstrated that MAP3K MEKK2 activation requires dimerization.

39 iescent MEKK2 preferentially binds MEK5, and MEKK2 activation results in ERK5 activation.

40 ion is an important regulatory mechanism for MEKK2 activation.

41 This mekk2 allele can rescue the mpk4 autoimmune phenotype in

42 MEKK2 also synergized with anti-CD3 antibody to activate

43 WNK1 phosphorylated both MEKK2 and -3 in vitro, and MEKK3 was activated by WNK1 i

44 MAPKKK/MEKK level protein kinases from mouse MEKK2 and -3, Drosophila melanogaster PK92B, Saccharomyc

45 In contrast to MEKK2 and 3, MEKK1 and 4 specifically associated with Ra

46 and in post-Golgi vesicular-like structures; MEKK2 and 4 were localized to distinct Golgi-associated

47 , it leads to accumulation of phosphorylated MEKK2 and activation of the downstream JNK signaling cas

48 e distinct MEK5 PB1 domain binding sites for MEKK2 and ERK5, with a C-terminal extension of the PB1 d

49 in inhibition of Src-dependent activation of MEKK2 and ERK5.

50 xpression and by blocking the interaction of MEKK2 and Lad.

51 MEKK2 and Lad/RIBP colocalize at the T cell contact site

52 ting cells, demonstrating cotranslocation of MEKK2 and Lad/RIBP during T cell activation.

53 MEKK2 and MEK5 encode Phox/Bem1p (PB1) domains that hete

54 Furthermore, co-immunoprecipitation of MEKK2 and MEK5 from cell lysates shows that they form a

55 y complex through interactions involving the MEKK2 and MEK5 PB1 domains and a 34-amino-acid C-termina

56 The findings define how the MEKK2 and MEK5 PB1 domains are uniquely used for differe

57 Expression of dominant negative mutants of MEKK2 and MEKK3 also blocked activation of ERK5 by WNK1.

58 MEKK2 and MEKK3 are differentially associated with signa

59 MEKK2 and MEKK3 are MAPK kinase kinases that activate th

60 The kinase domains of MEKK2 and MEKK3 are nearly identical, although their N-t

61 MEKK2 and MEKK3 are two closely related mitogen-activate

62 The PB1 domains of MEKK2 and MEKK3 bind the PB1 domain of MEK5 but do not s

63 We now show that MEKK2 and MEKK3 can in vivo activate IKK-alpha and IKK-b

64 Moreover, both MEKK2 and MEKK3 coimmunoprecipitated with endogenous WNK

65 to identify mutations in the closely linked MEKK2 and MEKK3 loci.

66 g the specific and unique requirement of the MEKK2 and MEKK3 PB1 domain in regulating ERK5 activation

67 demonstrate that lipopolysaccharide induced MEKK2 and MEKK3 phosphorylation on their regulatory seri

68 t the PB1 domain mediates the association of MEKK2 and MEKK3 with MEK5 and that the respective PB1 do

69 gen-activated protein kinase kinase kinases, MEKK2 and MEKK3, and this interaction may in part be med

70 on site, serine 519 and serine 526, in MAP3K MEKK2 and MEKK3, respectively.

71 Unlike MEKK2 and MEKK3, the C-terminal kinase domain of MEKK1 d

72 er of a tandemly duplicated gene family with MEKK2 and MEKK3.

73 d diverse substrate targeting by the MAP3Ks, MEKK2 and MEKK3.

74 inhibiting both tumor growth and metastasis; MEKK2 and MLK3 represent untargeted kinases in tumor bio

75 Knockdown of MEKK2 and MLK3 resulted in increased apoptosis in orthot

76 The screen identified two MAP3Ks, MEKK2 and MLK3, whose shRNA knockdown caused significant

77 In cells, MEKK2 and PRK2 are co-immunoprecipitated and PRK2 is act

78 strate that Smurf1 physically interacts with MEKK2 and promotes the ubiquitination and turnover of ME

79 We obtained five mutations in MEKK2 and seven mutations in MEKK3, all located within 2

80 Activation of MEKK2 and the ERK5 pathway by EGF and stress stimuli is

81 amino acids 228 to 282 in the N terminus of MEKK2, and expression of this motif blocks Lad-MEKK2 int

82 lot analysis of FLS demonstrated that MEKK1, MEKK2, and TAK1 were readily detectable and were subsequ

83 tch is recruited to activated MEKK1, but not MEKK2, and this novel scaffolding interaction is depende

84 d protein kinase/ERK kinase kinase (MEKK) 1, MEKK2, apoptosis-signal regulating kinase-1, TGF-beta ac

85 In turn, the abundance of MEKK2 appears to be under cellular surveillance such tha

86 Lad and MEKK2 are in a complex in resting cells.

87 This study identifies Rap1 and MEKK2 as critical upstream signaling molecules mediating

88 Mechanistically, we found that MEKK2 associated with inactive MEKK2 in the absence of 1

89 required for ERK5 activation by Src, Lad and MEKK2 association is required for Src activation of ERK5

90 e ERK5, whereas inhibition of either Rap1 or MEKK2 attenuates BDNF activation of ERK5.

91 segment, that this surface is important for MEKK2 autophosphorylation and dimerization, and that thi

92 Expression of T283A MEKK2 within a MEKK2(-/-) background enhanced stress-activated c-Jun N-

93 The MEKK2 binding site maps to amino acids 637-660 in PRK2,

94 Activated MEKK2 binds and activates MKK7, leading to JNK activatio

95 -3-3 proteins also interacted with MEKK1 and MEKK2, but not MEKK4.

96 DA-approved inhibitors with activity against MEKK2 can ameliorate NF1 skeletal pathology.

97 The human MEKK2 cDNA encoded a polypeptide of 619 amino acids and

98 onance energy transfer [FRET]) measuring YFP-MEKK2/CFP-MEK5 and CFP-MEK5/YFP-ERK5 interactions define

99 rthermore, we found that the endogenous Mip1-MEKK2 complex was dissociated transiently following epid

100 K2 has a high degree of homology with MEKK3, MEKK2-DD, unlike MEKK3-DD, also fails to restore TNF-alp

101 d to proceed similarly in the bone marrow of Mekk2-deficient and wild-type mice.

102 ajor subsets of thymic and spleen T cells in Mekk2-deficient mice were indistinguishable from those i

103 vity and response to BMP through controlling MEKK2 degradation.

104 that MEKK2 dimer formation in vivo augmented MEKK2-dependent JNK activation and JNK/AP-1 reporter gen

105 ization system, we further demonstrated that MEKK2 dimer formation in vivo augmented MEKK2-dependent

106 Moreover, prevention of MEKK2 dimer formation inhibited MEKK2-mediated JNK activ

107 Mip1 prevented MEKK2 activation by blocking MEKK2 dimer formation, which in turn blocked JNKK2, c-Ju

108 the NH2-terminal region is not required for MEKK2 dimer formation.

109 K2-interacting protein, Mip1, that regulates MEKK2 dimerization and activation by forming a complex w

110 We mapped the MEKK2 dimerization motif in its catalytic domain and sho

111 We find that MEKK2 dimerizes by a surface centered on the alphaG heli

112 each displaying skeletal defects, Nf1(fl/fl);Mekk2(-/-);Dmp1-Cre mice show an amelioration of NF1-ass

113 mature osteoblasts (Nf1(fl/fl);Dmp1-Cre) and Mekk2(-/-) each displaying skeletal defects, Nf1(fl/fl);

114 Here we showed that the MAPK kinase kinases MEKK2 (encoded by Map3k2) and MEKK3 (encoded by Map3k3)

115 MEKK2(-/-) ESMC also lost receptor-mediated stimulation

116 IgE or c-Kit ligand was markedly reduced in MEKK2(-/-) ESMC relative to wild-type ESMC.

117 EGF is similarly inhibited by loss of Lad or MEKK2 expression and by blocking the interaction of MEKK

118 ired for ERK5 activation in response to EGF, MEKK2 expression is required for ERK5 activation by Src,

119 d expression and targeted gene disruption of MEKK2 expression results in loss of epidermal growth fac

120 MEKK2 expression stimulates BMK1/ERK5 activity, the down

121 ufficient because activation of JNK using an MEKK2 expression vector did not mimic the sensitizing ef

122 Biochemical activation of MEKK2 follows TCR stimulation, and expression of a domin

123 found that the inactive, non-phosphorylated MEKK2 formed significantly more dimers than the phosphor

124 Thus, MEKK2 functions as a MAP3K in the ERK pathway in osteobl

125 inhibited by MAP/ERK kinase (MEK) kinase 2 (MEKK2) gene disruption.

126 Although MEKK2 has a high degree of homology with MEKK3, MEKK2-DD

127 MEKK2 has its kinase domain in the COOH-terminal moiety

128 The NH(2)-terminal moiety of MEKK2 has no signature motif that would suggest a define

129 Furthermore, MEKK2 immunoprecipitates activated c-Jun in an IL-1 depe

130 In vitro kinase assays using MEKK2 immunoprecipitates demonstrated that IL-1 increase

131 CrRLK1L, and acts genetically downstream of MEKK2 in regulating SUMM2 activation.

132 -type ESMC, demonstrating the specificity of MEKK2 in signaling cytokine gene regulation.

133 we found that MEKK2 associated with inactive MEKK2 in the absence of 14-3-3 binding, which led to tra

134 at MEK5 is a specific downstream effector of MEKK2 in the BMK1/ERK5 pathway.

135 ation, and expression of a dominant-negative MEKK2 inhibits TCR-mediated conjugate stabilization and

136 MEKK2 integrates stress and mitogenic signals to the act

137 In this study, we identified a novel MEKK2-interacting protein, Mip1, that regulates MEKK2 di

138 KK2, and expression of this motif blocks Lad-MEKK2 interaction, resulting in inhibition of Src-depend

139 aken together, our results showed that human MEKK2 is a key signaling molecule for T-cell receptor/CD

140 MEKK2 is a member of the mitogen-activated protein kinas

141 am of NF1 loss in the skeleton, finding that MEKK2 is a novel component of a noncanonical ERK pathway

142 These data indicate that MEKK2 is a potent activator of the JNK pathway in FLS an

143 on of rapid activation of NF-kappaB, whereas MEKK2 is important in controlling the delayed activation

144 Furthermore, BDNF stimulation of MEKK2 is regulated by Rap1.

145 We have found that MEKK2 is regulated through a phosphorylation-dependent a

146 e to UV irradiation was normal, showing that MEKK2 is required for receptor signaling but not for cel

147 Follow-up genetic analyses indicated that MEKK2 is required for the mekk1, mkk1 mkk2, and mpk4 aut

148 Our data indicate that activation of Rap1 or MEKK2 is sufficient to stimulate ERK5, whereas inhibitio

149 MEKK2 is the first MAP3K shown to be required for mast c

150 MEK kinase 2 (MEKK2) is a 70-kDa protein serine/threonine kinase that

151 maging demonstrate that T cell MEK kinase 2 (MEKK2) is translocated to the T cell/antigen-presenting

152 h it does not reduce the basal expression of MEKK2, it does prevent the upregulation of MEKK2 that is

153 precipitation of, respectively, MEKK2-JNKK2, MEKK2-JNK1, and JNKK2-JNK1, indicating that the interact

154 KK2-JNK1, indicating that the interaction of MEKK2, JNKK2, and JNK1 is synergistic.

155 mation of a tripartite complex consisting of MEKK2, JNKK2, and JNK1.

156 mented the coprecipitation of, respectively, MEKK2-JNKK2, MEKK2-JNK1, and JNKK2-JNK1, indicating that

157 e JNK1 was activated more efficiently in the MEKK2-JNKK2-JNK1 complex than was the JNK1 excluded from

158 a MAPKKK, a MAPKK, and a MAPK molecule like MEKK2-JNKK2-JNK1 is likely to be responsible for the eff

159 No scaffold protein was required for the MEKK2-JNKK2-JNK1 tripartite-complex formation.

160 ne the 2.4 angstrom crystal structure of the MEKK2 kinase domain in complex with the small molecule i

161 ted mice carrying a targeted mutation in the Mekk2 locus.

162 MEKK2 (MAP/ERK kinase kinase-2) is a serine/threonine ki

163 n did the wild-type T cells, suggesting that MEKK2 may be involved in controlling the strength of T-c

164 In conclusion, we found that MEKK2 may be required for controlling the strength of TC

165 revention of MEKK2 dimer formation inhibited MEKK2-mediated JNK activation.

166 wn of Mip1 expression by siRNA augmented the MEKK2-mediated JNK and AP-1 reporter activation.

167 recipitates demonstrated that IL-1 increased MEKK2-mediated phosphorylation of the key MAPKKs that ac

168 MEKK2, MEK5, and extracellular signal-regulated kinase 5

169 MEKK2, MEK5, and extracellular signal-related kinase 5 (

170 r mutation of the MEKK2 PB1 domain abolishes MEKK2-MEK5 complexes, demonstrating that the PB1 domain

171 which might correlate with a higher affinity MEKK2-MEK5 interaction.

172 t the PB1 domain interaction is required for MEKK2-MEK5 interactions.

173 that also binds ERK5, functionally forming a MEKK2-MEK5-ERK5 complex.

174 s regulated in part by the signaling complex MEKK2-MEK5-ERK5.

175 ain residues critical for the interaction of MEKK2/MEK5 and MEK5/ERK5 required for activation of the

176 discovery that root growth in a triple mekk1 mekk2 mekk3 mutant (mekk1/2/3), defective in a set of th

177 t, arsenite-mediated JNK activation requires MEKK2, MEKK3 and MEKK4.

178 Herein, we analyze the functional role of MEKK2, MEKK3, and MEK5 PB1 domains in the ERK5 activatio

179 is encoded within the N-terminal portion of MEKK2, MEKK3, and MEK5.

180 Mekk2(-/-) mice are viable and fertile.

181 y in FLS and that signal complexes including MEKK2, MKK4, MKK7, and/or JNK are potential therapeutic

182 by antigen cross-linking is dependent on the MEKK2-MKK7 pathway, and cytokine production in mast cell

183 , we showed that MEKK2 protein levels mirror MEKK2 mRNA levels.

184 e A23187, was inhibited by dominant negative MEKK2 mutants.

185 ells was also inhibited by dominant negative MEKK2 mutants.

186 Neither MEKK2 nor MLK3 have been previously shown to regulate tu

187 Targeted disruption of the MEKK2 or MEKK1 gene was used to abolish expression of th

188 The free PB1 domain of MEKK2 or MEKK3 functions effectively to inhibit the ERK5

189 Expression in cells of the MEKK2 or MEKK3 PB1 domain inhibits ERK5 activation, wher

190 beta abolish NF-kappaB activation induced by MEKK2 or MEKK3, thereby providing evidence that these IK

191 IkappaBalpha:NF-kappaB/IKK complex, whereas MEKK2 participates in assembling the IkappaBbeta:NF-kapp

192 Deletion or mutation of the MEKK2 PB1 domain abolishes MEKK2-MEK5 complexes, demonst

193 ter of basic amino acids in the front of the MEKK2 PB1 domain binding to the back-end acidic clusters

194 moiety, including the acidic cluster of the MEKK2 PB1 domain, is not required for MEK5 binding and b

195 Quiescent MEKK2 preferentially binds MEK5, and MEKK2 activation re

196 C-related kinase 2 (PRK2) was found to bind MEKK2; PRK2 has been previously shown to bind RhoA and t

197 We next analyzed a T-DNA insertion in the MEKK2 promoter region and found that although it does no

198 se brain by decreasing PTEN, RB1, and MAP3K2/MEKK2 protein expression, thereby increasing AKT activat

199 lly, using mass spectrometry, we showed that MEKK2 protein levels mirror MEKK2 mRNA levels.

200 In contrast, MEKK2 recruitment of MEK5 is dependent on PB1 domain int

201 JNK1 activation, whereas the related kinase MEKK2 regulates ERK5 activation.

202 results suggest a novel mechanism underlying MEKK2 regulation and activation.

203 Together, our data suggest a novel model for MEKK2 regulation and activation.

204 MEKK2 activation of PRK2 is independent of MEKK2 regulation of the c-Jun NH(2)-terminal kinase path

205 activated MPK4 is responsible for regulating MEKK2 RNA abundance.

206 promoter activity requires a functional Lad-MEKK2 signaling complex.

207 f multiple downstream targets, including the MEKK2 signaling pathway, inducing osteoblast differentia

208 Expression of JNK1, JNKK2, and MEKK2 significantly augmented the coprecipitation of, re

209 n was not blocked but moderately enhanced in Mekk2(-/-) T cells.

210 nase nor p38 MAPK activation was affected in Mekk2(-/-) T cells.

211 However, Mekk2(-/-) T-cell proliferation was augmented in respons

212 rn blot analysis demonstrated immunoreactive MEKK2, TAK1, and trace amounts of MEKK3 but not MEKK1 or

213 f MEKK2, it does prevent the upregulation of MEKK2 that is observed in mpk4 plants.

214 Consistently, Mekk2(-/-) thymocytes were more susceptible than wild-ty

215 MEKK2 translocation occurs more rapidly as the antigen c

216 d stimulation of T cells led to induction of MEKK2 tyrosine phosphorylation.

217 5 activation, whereas expression of a mutant MEKK2 unable to bind the MEK5 PB1 domain or expression o

218 In T cells, MEKK2 was found to be a strong activator of JNK but not

219 that strong and specific JNK1 activation by MEKK2 was mediated by the MAPKK JNK kinase 2 (JNKK2) rat

220 We found that MEKK2 was phosphorylated at Thr-283, which resulted in d

221 MEKK2 was required for epidermal growth factor receptor

222 Northern blot analysis showed that MEKK2 was ubiquitously expressed, with the highest level

223 kinase (JNK) subgroup of MAPK by the MAPKKK MEKK2, we found that strong and specific JNK1 activation

224 To elucidate the in vivo function of MEKK2, we generated mice carrying a targeted mutation in

225 Endogenous 14-3-3 protein and MEKK1 and MEKK2 were similarly distributed in the cell, consistent

226 MEK5 blocked the activation of BMK1/ERK5 by MEKK2, whereas activation of c-Jun N-terminal kinase (JN

227 Expression of T283A MEKK2 within a MEKK2(-/-) background enhanced stress-act