ライフサイエンスコーパス: eIF5

1 n of mRNA and that it binds to eIF2alpha and eIF5.

2 the minimal segments of eIF2beta, eIF3c, and eIF5.

3 hown previously for the C-terminal domain of eIF5.

4 t Ser-387 and Ser-388 near the C-terminus of eIF5.

5 rified bacterially expressed recombinant rat eIF5.

6 and hydrolysis of eIF2-bound GTP induced by eIF5.

7 bipartite motif in the carboxyl terminus of eIF5.

8 e tif5-7A mutation in the bipartite motif of eIF5.

9 3, ternary complex (eIF2-GTP-Met-tRNAi), and eIF5.

10 east and mammals, that stably interacts with eIF5.

11 notypes are mitigated by the SUI5 variant of eIF5.

12 previously, including eIF1A, eIF1, eIF2, and eIF5.

13 Overexpression of eIF5, 5MP1 and 5MP2, the second human paralog, promotes

14 In Saccharomyces cerevisiae, eIF5, a protein of 45346Da, is encoded by a single-copy

15 The C-terminal domain (CTD) of eIF5, a W2-type HEAT domain, mediates its interaction wi

16 tution mutagenesis at Ser-387 and Ser-388 of eIF5 abolishes phosphorylation by the purified kinase as

17 eIF5 also forms a complex with eIF2 by interacting with

18 The fifth Prt1p-associated protein was eIF5, an initiation factor not previously known to inter

19 carcinoma, we propose that overexpression of eIF5 and 5MP induces translation of ATF4 and potentially

20 is maintained through balanced expression of eIF5 and 5MP.

21 By modulating eIF5 and 5MP1 expression in combination with ribosome pr

22 mplex with Met-tRNA(i)(Met), eIF2, eIF3, and eIF5 and binds near the P-site.

23 To further characterize eIF5 and delineate its role in GCN4 translational contro

24 with phosphorylated eIF2, eIF2B outcompetes eIF5 and destabilizes TC.

25 y, rnp1 also reduces the levels of 40S-bound eIF5 and eIF1 and increases leaky scanning at the GCN4 u

26 interaction with the AUG recognition factors eIF5 and eIF1.

27 no terminus of NIP1 can bind concurrently to eIF5 and eIF1.

28 43 S complex triggers an interaction between eIF5 and eIF1A, resulting in a shift in the equilibrium

29 Native wheat eIF5 and eIF2alpha were found to have phosphorylation si

30 eIF2beta mediate the binding of eIF2 to both eIF5 and eIF2B.

31 Thus, eIF5 and eIF2Bepsilon employ the same sequence motif to

32 nus abolishes its in vitro interactions with eIF5 and eIF2beta but not that with eIF3c.

33 on 17-21 suppresses the Sui(-) phenotypes of eIF5 and eIF2beta mutations and increases leaky scanning

34 his, both mutations diminished 40S-bound TC, eIF5 and eIF3 in vivo, and deltaC impaired TC recruitmen

35 that a specific physical interaction between eIF5 and eIF3 may play an important role in the function

36 Alternative model that eIF5 and eIF5B cause 43S pre-initiation complex rearrang

37 Here we show that eIF5 and eIF5B together stimulate 48S IC formation influ

38 NIP1/eIF3c interacts directly with eIF1 and eIF5 and indirectly through eIF5 with the eIF2-GTP-Met-t

39 y, Sui1p also interacts with Nip1p, and both eIF5 and Sui1p have been implicated in accurate recognit

40 Thus, eIF5 and Sui1p may be recruited to the 40S ribosomes thr

41 ression increases the abundance of both eIF2/eIF5 and TC/eIF5 complexes, thereby impeding eIF2B react

42 ion of energetic interactions between eIF1A, eIF5 and the AUG codon in an in vitro reconstituted yeas

43 ggests that the specific interaction between eIF5 and the beta subunit of eIF2 may be critical for th

44 c residues are conserved at the C-termini of eIF5 and the catalytic (epsilon) subunit of eIF2B.

45 eIF5 and the eIF2Bvarepsilon catalytic subunit possess a

46 as its isolated G domain, binds directly to eIF5 and the epsilon subunit of eIF2B, and we map the in

47 model in which the GTPase-activating factor eIF5 and the guanine-nucleotide exchange factor eIF2B mo

48 have critical functions in 40S binding, with eIF5 and the TIF32-CTD performing redundant functions.

49 The eIF2, eIF5, and eIF1 all have been implicated in stringent sel

50 tion factors in vitro, including eIF3, eIF1, eIF5, and eIF1A.

51 otic translation initiation factor 3 (eIF3), eIF5, and eIF2, but not with other translation initiatio

52 phorylate eIF2alpha, eIF2beta, eIF3c, eIF4B, eIF5, and histone deacetylase 2B but did not phosphoryla

53 e multifactor complex containing eIF1, eIF3, eIF5, and TC, showing that eIF1 promotes PIC assembly in

54 -NTD and TIF32-CTD) that interact with eIF1, eIF5, and the eIF2/GTP/Met-tRNA(i)(Met) ternary complex.

55 initiation factor 1 (eIF1), eIF1A, eIF3, and eIF5, and the resulting preinitiation complex (PIC) join

56 nd Arabidopsis thaliana eIF2alpha, eIF2beta, eIF5, and wheat eIF3c.

57 We also show that eIF5 antagonizes binding of eIF1 to the complex and that

58 Thus, the bipartite motif in eIF5 appears to be multifunctional, stimulating its recr

59 on, we have used 32P-labeled recombinant rat eIF5 as a probe in filter overlay assay to identify eIF5

60 In vivo, tif5-7A eliminated eIF5 as a stable component of the pre-initiation complex

61 eletion mutants identified the C terminus of eIF5 as the eIF2beta-binding region.

62 n cells suggesting that CK II phosphorylates eIF5 at these two serine residues in vivo as well.

63 Furthermore, both yeast and mammalian eIF5 bind to the beta subunit of either mammalian or yea

64 etween amino acids 68 and 89, as the primary eIF5-binding region of eIF2beta.

65 First, eIF5 binds eIF2/GTP/Met-tRNA(i)(Met) ternary complex (TC

66 We show that eIF5 binds to the extreme c/Nip1-NTD (residues 1-45) and

67 The eIF5 bipartite motif is also important for its interacti

68 ely 40% of the total eIF2 is associated with eIF5 but lacks tRNA(i)(Met).

69 First, the eIF4G-RS1 interaction with the eIF5 C-terminal domain (eIF5-CTD) directly links eIF4G t

70 ever, the binding sites for these factors on eIF5-C-terminal domain (CTD) have not been known.

71 We show that yeast eIF5 can bridge interaction in vitro between eIF3 and eI

72 Additionally, we show that rat eIF5 can functionally substitute yeast eIF5 in translati

73 hen TC is formed with unphosphorylated eIF2, eIF5 can out-compete eIF2B to stabilize TC/eIF5 complexe

74 d by eIF2 phosphorylation and the novel eIF2/eIF5 complex lacking tRNA(i)(Met).

75 We propose that the eIF2/eIF5 complex represents a cytoplasmic reservoir for eIF2

76 et) ternary complex (TC) binds the eIF3/eIF1/eIF5 complex to form the multifactor complex (MFC), wher

77 ernary complex (TC) interacts with eIF3-eIF1-eIF5 complex to form the multifactor complex (MFC), whil

78 eases the abundance of both eIF2/eIF5 and TC/eIF5 complexes, thereby impeding eIF2B reaction and MFC

79 , eIF5 can out-compete eIF2B to stabilize TC/eIF5 complexes.

80 y altering the off-rate of GDP from eIF2*GDP/eIF5 complexes.

81 Like other GTPase-activating proteins, eIF5 contains an invariant arginine residue (Arg-15) at

82 gion of basic residues, and that eIF4G binds eIF5-CTD at an interface overlapping with the acidic are

83 Here we present a homology model for eIF5-CTD based on the HEAT domain of eIF2Bepsilon.

84 ered event involving specific enhancement of eIF5-CTD binding to eIF3 on its binding to eIF2beta.

85 Interestingly, eIF5-CTD bound simultaneously to the eIF4G subunit of th

86 ture-sensitive phenotype of tif5-7A altering eIF5-CTD by increasing interaction of the mutant eIF5 wi

87 In addition, stronger restriction of eIF5-CTD function at an elevated temperature led to fail

88 permissive temperature, directly implicating eIF5-CTD in the eIF2/GTP/Met-tRNA(i)Met ternary complex

89 This latter result directly implicates eIF5-CTD in the process of accurate scanning for, or rec

90 We propose that the primary function of eIF5-CTD is to serve as an assembly guide by rapidly pro

91 Taken together, our results indicate that eIF5-CTD plays a critical role in both the assembly of t

92 rearrangement of interactions involving the eIF5-CTD promotes mRNA recruitment through mRNA binding

93 ns altering eIF4G-RS1, eIF2beta-K-boxes, and eIF5-CTD restore the accuracy of start codon selection i

94 We propose that eIF5-CTD stimulates binding of Met-tRNA(i)(Met) and mRNA

95 evidence indicating that the association of eIF5-CTD with eIF2beta strongly enhances its binding to

96 Met-tRNA(i)(Met), and its C-terminal domain (eIF5-CTD) bridges interaction between eIF2 and eIF3/eIF1

97 interaction with the eIF5 C-terminal domain (eIF5-CTD) directly links eIF4G to the preinitiation comp

98 The carboxyl-terminal domain (CTD) of eIF5 (eIF5-CTD) has been identified as a potential nucleation

99 The nine point mutations clustered in the eIF5-CTD, which contains two conserved aromatic/acidic b

100 The tif5-7A mutation in eIF5-CTD, which destabilizes the multifactor complex in

101 subunit in vitro in a manner reversed by the eIF5-CTD.

102 ionally, alanine substitution mutagenesis of eIF5 defined Lys-33 and Lys-55 as also critical for eIF5

103 Binding analyses with recombinant rat eIF5 deletion mutants identified the C terminus of eIF5

104 detect 43 S initiation complex formation and eIF5-dependent GTP hydrolysis revealed no differences be

105 hese mutants were also severely defective in eIF5-dependent GTP hydrolysis, in 80S initiation complex

106 terminal region of eIF5 is also required for eIF5-dependent GTP hydrolysis.

107 ciently joined 60 S ribosomal subunits in an eIF5-dependent reaction to form a functional 80 S initia

108 ciently joined 60 S ribosomal subunits in an eIF5-dependent reaction to form a functional 80 S initia

109 lity to stimulate translation of mRNAs in an eIF5-dependent yeast cell-free translation system.

110 Analysis of the polysome profiles of eIF5-depleted cells showed greatly diminished polysomes

111 40S-bound mRNA strongly accumulated in eIF5-depleted cells, even though MFC binding to 40S subu

112 h MFC binding to 40S subunits was reduced by eIF5 depletion.

113 f the chromosomal copy of the TIF5 gene, the eIF5 double-point mutants allowed only slow growth of th

114 ay play an important role in the function of eIF5 during translation initiation in eukaryotic cells.

115 eIF5, eIF1 and HCR1 co-purified with this subcomplex, bu

116 xes) of eIF2beta bind three common partners, eIF5, eIF1, and mRNA.

117 ation: it binds to, and stabilizes, the eIF3-eIF5- eIF1-eIF2 multifactor complex and is required for

118 ct of an eIF5 mutation that weakens the NIP1-eIF5-eIF2 connection.

119 Overexpressing the NIP1-NTD sequestered eIF1-eIF5-eIF2 in a defective subcomplex that derepressed GCN

120 in the yeast multifactor complex (eIF1-eIF3-eIF5-eIF2-GTP-Met-tRNA(i)(Met)).

121 dings suggest the occurrence of an eIF3/eIF1/eIF5/eIF2 multifactor complex, which was observed in cel

122 1:eIF2 complex, nearly comparable to that of eIF5:eIF2 complex produced by eIF5 overexpression.

123 agreement with this, archaea appear to lack eIF5, eIF2B and the lysine-rich binding domain for these

124 al approach to investigate the importance of eIF5-eIF2beta interaction in eIF5 function.

125 These findings suggest that eIF5-eIF2beta interaction plays an essential role in eIF

126 The carboxyl-terminal domain (CTD) of eIF5 (eIF5-CTD) has been identified as a potential nucle

127 yotic initiation factor 4AI (eIF4AI), eIF4G, eIF5, eIF6, eukaryotic elongation factor 1A-1 (eEF1A-1),

128 F5 were dependent on exogenously added yeast eIF5 for efficient translation of mRNAs in vitro.

129 e data uncover competition between eIF2B and eIF5 for TC and identify that phosphorylated eIF2-GTP tr

130 ement with effective competition of 5MP with eIF5 for the main substrate, eIF2.

131 resses non-AUG translation by competing with eIF5 for the Met-tRNAi-binding factor eIF2.

132 stem that was dependent on exogenously added eIF5 for translation of mRNAs in vitro.

133 Met-tRNAf.eIF2.GTP ternary complex, and (b) eIF5 forms a specific complex with eIF2 suggests that th

134 Eukaryotic translation initiation factor 5 (eIF5) forms a complex with eIF2 by interacting with the

135 st that prior to AUG recognition it prevents eIF5 from binding to a key site in the PIC required for

136 ted in dissociation of TIF32, NIP1, HCR1 and eIF5 from eIF3 in vivo, and destroyed 40S ribosome bindi

137 Depletion of eIF5 from this mutant yeast strain resulted in inhibitio

138 2beta interaction plays an essential role in eIF5 function in eukaryotic cells.

139 fined Lys-33 and Lys-55 as also critical for eIF5 function in vitro and in vivo.

140 erize the molecular interactions involved in eIF5 function, we have used 32P-labeled recombinant rat

141 e importance of eIF5-eIF2beta interaction in eIF5 function.

142 esidues in a bipartite motif as critical for eIF5 function.

143 scussed and provide additional evidence that eIF5 functions as a GTPase-activating protein.

144 To identify eIF5 functions crucial for accurate initiation, we inves

145 eIF5 functions in start site selection as a GTPase accel

146 functional but a rapidly degradable form of eIF5 fusion protein was synthesized from the repressible

147 eIF5-G31R altered regulation of Pi release, accelerating

148 (-) phenotypes produced by the eIF1-D83G and eIF5-G31R mutations.

149 henotype) and was lethal in cells expressing eIF5-G31R that is hyperactive in stimulating GTP hydroly

150 on, as was the Sui(-) phenotype conferred by eIF5-G31R.

151 eIF2 GDP/GTP status is regulated by eIF5 (GAP and GDI functions) and eIF2B (GEF and GDF acti

152 ndings provide support for the importance of eIF5 GDI activity in vivo and demonstrate that eIF2beta

153 uppressor mutation in eIF2beta that prevents eIF5 GDI and alters cellular responses to reduced eIF2B

154 e kinetics of eIF2 release from the eIF2*GDP/eIF5 GDI complex and determine the effect of eIF2B on th

155 GDF) that can recruit eIF2 from the eIF2*GDP/eIF5 GDI complex prior to GEF action.

156 we show that the eIF2beta mutation prevents eIF5 GDI stabilizing nucleotide binding to eIF2, thereby

157 Finally, eIF5 GDP dissociation inhibition (GDI) activity can anta

158 aining temperature-sensitive mutation in the eIF5 gene allowed us to construct a cell-free translatio

159 Two proteins regulate its G-protein cycle: eIF5 has both GTPase-accelerating protein (GAP) and GDP

160 - and C-terminal domains of TIF32/eIF3a, and eIF5 have critical functions in 40S binding, with eIF5 a

161 These results indicate that the eIF5 HEAT domain is a critical nucleation core for prein

162 5 to eIF2beta but not to eIF3-Nip1p, while a eIF5 hexamutant (E345A,E346A, E347A,E384A,E385A,E386A) s

163 th of this DeltaTIF5 yeast strain, while the eIF5 hexamutant was unable to support cell growth and vi

164 nternal deletion of residues 50-100 of yeast eIF5 impairs the interaction with recombinant eIF2gamma-

165 that hydrolysis of eIF2-bound GTP induced by eIF5 in 48S complexes is necessary but not sufficient fo

166 which can functionally substitute for yeast eIF5 in complementing in vivo a genetic disruption of th

167 st eIF1, here we locate the binding site for eIF5 in its N-terminal tail and at a basic/hydrophobic s

168 nied by the movement of the eIF1A CTT toward eIF5 in order to trigger release of phosphate from eIF2,

169 Subsequent work implicated eIF5 in rearrangement of the preinitiation complex (PIC)

170 Here we define new regulatory functions of eIF5 in the recycling of eIF2 from its inactive eIF2.GDP

171 ydrolysis of eIF2-bound GTP is stimulated by eIF5 in the scanning PIC, but completion of the reaction

172 t rat eIF5 can functionally substitute yeast eIF5 in translation of mRNAs in vitro as well as in comp

173 To understand the function of eIF5 in vivo, we constructed a conditional mutant yeast

174 tro, is likely the rate-limiting function of eIF5 in vivo.

175 rgeted at TIF5, the structural gene encoding eIF5 in yeast (Saccharomyces cerevisiae).

176 Nip1p bound to eIF5 in yeast two-hybrid and in vitro protein binding as

177 Consistently, eIF5 increases, whereas 5MP decreases translation of NAT

178 from transfected cell lysates contains bound eIF5 indicating that a specific physical interaction bet

179 tream of 48S complex formation, in promoting eIF5-induced GTP hydrolysis and eIF2/GDP release from th

180 w they were assembled, that are required for eIF5-induced hydrolysis of eIF2-bound GTP and/or subunit

181 We report that eIF5-induced hydrolysis of eIF2-bound GTP in 48S complex

182 eIF5-induced hydrolysis of eIF2-bound GTP is essential f

183 the stage of ribosomal subunit joining after eIF5-induced hydrolysis of eIF2-bound GTP.

184 Removal of CK2 phosphorylation sites from eIF5 inhibits the CK2-mediated increase in eIF5 interact

185 a probe in filter overlay assay to identify eIF5-interacting proteins in crude initiation factor pre

186 m eIF5 inhibits the CK2-mediated increase in eIF5 interaction with eIF1 and eIF3c in pulldown assays

187 Bvarepsilon with eIF2 normally disrupts eIF2/eIF5 interaction.

188 Eukaryotic translation initiation factor 5 (eIF5) interacts in vitro with the 40 S initiation comple

189 Eukaryotic translation initiation factor 5 (eIF5) interacts with the 40 S initiation complex (40 S.m

190 Eukaryotic translation initiation factor 5 (eIF5) interacts with the 40S initiation complex (40S*eIF

191 Eukaryotic translation initiation factor 5 (eIF5) interacts with the 40S initiation complex (40S-eIF

192 Eukaryotic translation initiation factor 5 (eIF5) interacts with the 40S ribosomal initiation comple

193 at 5MP1 is a partial mimic and competitor of eIF5, interfering with the key steps by which eIF5 regul

194 mimicked by eIF5 overexpression, which turns eIF5 into translational inhibitor, thereby promoting tra

195 Second we show that eIF5 is a critical component of the eIF2(alphaP) regulat

196 C terminus of eIF5, the N-terminal region of eIF5 is also required for eIF5-dependent GTP hydrolysis.

197 Thus, eIF5 is an excellent candidate for the direct partner of

198 The translation factor eIF5 is an important partner of eIF2, directly modulatin

199 In Saccharomyces cerevisiae, eIF5 is encoded by a single copy essential gene, TIF5, t

200 However when TC/eIF5 is formed with phosphorylated eIF2, eIF2B outcompet

201 binding of the eIF4G HEAT domain to eIF1 and eIF5 is important for maintaining the integrity of the s

202 ongly that the interaction between eIF1A and eIF5 is involved in maintaining the fidelity of start co

203 nally, we show that the C-terminal domain of eIF5 is responsible for the factor's activity in antagon

204 eIF5 is the GTPase activating protein (GAP) for the eIF2

205 y half of cellular eIF2 forms a complex with eIF5 lacking Met-tRNA(i)(Met), and here we investigate i

206 nalysis of maximally in vitro phosphorylated eIF5 localized the major phosphorylation sites at Ser-38

207 and eIF3c in pulldown assays and reduces the eIF5-mediated stimulation of translation initiation in v

208 Furthermore, regulatory protein termed eIF5-mimic protein (5MP) can bind eIF2 and inhibit gener

209 AUG initiation is controlled in part, by the eIF5-mimic protein (5MP).

210 , previously termed BZW2 and renamed here as eIF5-mimic protein 1 (5MP1).

211 ession of a translational inhibitor protein, eIF5-mimic protein 1 (5MP1, also known as BZW2) in mamma

212 plex (40S.Met-tRNA(i).eIF2.GTP), promoted by eIF5, must occur only when the complex has selected the

213 IF2Bvarepsilon segment similarly exacerbates eIF5 mutant phenotypes, supporting the ability of eIF2Bv

214 Previous work suggested that the eIF5 mutation G31R/SUI5 elevates initiation at UUG codon

215 IF32 exacerbated the initiation defect of an eIF5 mutation that weakens the NIP1-eIF5-eIF2 connection

216 he direct interaction at eIF1-KH also places eIF5 near the decoding site of the 40 S subunit.

217 along with our earlier observations that (a) eIF5 neither binds nor hydrolyzes free GTP or GTP bound

218 main within translation initiation factor 5 (eIF5); no members of this family of proteins have been s

219 gamma, has been reported to directly bind to eIF5 or eIF2B.

220 No interaction with recombinant eIF5 or the initiation site RNA GCCACAAUGGCA was detecte

221 xamined the effects of depleting eIF2, eIF3, eIF5, or eIF4G in Saccharomyces cerevisiae cells on bind

222 erestingly, the TC increase is suppressed by eIF5 overexpression and Gcn2p expression.

223 Moreover, we show that eIF5 overexpression does not generate aberrant MFC lacki

224 eIF5 overexpression increases the abundance of both eIF2

225 t of eIF2 phosphorylation can be mimicked by eIF5 overexpression, which turns eIF5 into translational

226 ble to that of eIF5:eIF2 complex produced by eIF5 overexpression.

227 account for nearly 90% of the total in vitro eIF5 phosphorylation.

228 shown that the translation initiation factor eIF5 plays an important role in the selection of the AUG

229 However, the mechanism that prevents the eIF5-promoted GTP hydrolysis, prior to AUG selection by

230 This interaction is essential for eIF5-promoted hydrolysis of GTP bound to the 40 S initia

231 ructure of mRNA are necessary for preventing eIF5-promoted hydrolysis of GTP in the 40S preinitiation

232 he absence of Fun12p (eIF5B), or a defect in eIF5, proteins involved in 60S ribosomal subunit joining

233 Depleting eIF2, eIF3, or eIF5 reduced 40S binding of all constituents of the mult

234 IF5, interfering with the key steps by which eIF5 regulates eIF2 function.

235 In vivo, co-overexpression of eIF1 or eIF5 reverses the genetic suppression of an eIF4G HEAT d

236 We conclude that both of eIF5's functions, regulating Pi release and stabilizing

237 Further characterization of mutant eIF5 showed that the mutant protein, expressed in Escher

238 omplex (MFC) comprising eIF1, eIF2, eIF3 and eIF5, similar to the MFC reported in yeast and plants.

239 We observed that eIF5 specifically interacted with the beta subunit of in

240 First we show that eIF5 stabilizes the binding of GDP to eIF2 and is theref

241 In the absence of eIF1, eIF5-stimulated hydrolysis of eIF2-bound GTP occurred at

242 The eIF5 stimulates GTP hydrolysis by the eIF2/GTP/Met-tRNA(

243 eIF5 stimulates hydrolysis of eIF2-bound GTP and eIF2 is

244 The factor eIF5 stimulates hydrolysis of GTP by eIF2 upon AUG codon

245 eIF5 stimulates the GTPase activity of eIF2 bound to Met

246 initiation phase of eukaryotic translation, eIF5 stimulates the hydrolysis of GTP bound to eIF2 in t

247 Mutations in these distinct eIF5 surface areas impair GCN4 translational control by

248 ction and identify conserved residues within eIF5 that are necessary for this role.

249 Mutations in both eIF1A and eIF5 that increase initiation at non-AUG codons in vivo

250 coordinates an interaction between eIF1 and eIF5 that inhibits GTP hydrolysis at non-AUG codons.

251 ltifactor complex (MFC) with eIF1, eIF2, and eIF5 that stimulates Met-tRNA(i)(Met) binding to 40S rib

252 e N-terminal domain (NTD) of NIP1 bridged by eIF5, the C-terminal domain (CTD) of TIF32 binds eIF2 di

253 IF2 beta-binding region at the C terminus of eIF5, the N-terminal region of eIF5 is also required for

254 ty of eIF2 are translation factors eIF2B and eIF5, thought to primarily function with eIF2-GDP and TC

255 ations, enhance the ability of overexpressed eIF5 to compete for eIF2, indicating that interaction of

256 ach caused a severe defect in the binding of eIF5 to eIF2beta but not to eIF3-Nip1p, while a eIF5 hex

257 g equivalent to the published value of human eIF5 to eIF2beta, in agreement with effective competitio

258 er, its most important function is to anchor eIF5 to other components of the 48S complex in a manner

259 monstrate that eIF2beta acts in concert with eIF5 to prevent premature release of GDP from eIF2gamma

260 ine caused a severe defect in the ability of eIF5 to promote GTP hydrolysis from the 40 S initiation

261 as evaluated by site-directed mutagenesis of eIF5 to remove CK2 phosphorylation sites.

262 2gamma-G domain and abolishes the ability of eIF5 to stimulate eIF2 GTPase activity in translation in

263 iple segments reduced the binding of eIF1 or eIF5 to the NIP1-NTD.

264 nit, which mediates eIF3 binding to eIF1 and eIF5, to semirandom mutagenesis to investigate the molec

265 of the GEF catalytic subunit eIF2Bepsilon or eIF5, using yeast as a model.

266 ltifactor complex (MFC) with eIF2, eIF3, and eIF5 via multiple interactions with the MFC constituents

267 The importance of CK2 phosphorylation of eIF5 was evaluated by site-directed mutagenesis of eIF5

268 Furthermore, lysates of cells depleted of eIF5 were dependent on exogenously added yeast eIF5 for

269 on, moves closer to the N-terminal domain of eIF5 when the PIC encounters an AUG codon.

270 me mutations also abolish phosphorylation of eIF5 when transfected into mammalian cells suggesting th

271 eal aIF2beta and the eukaryotic eIF2beta and eIF5, when combined with the structural results in the w

272 Furthermore, unlike wild-type rat eIF5, which can functionally substitute for yeast eIF5 i

273 re three times as abundant as eIF1, eIF2 and eIF5, while eIF3 is half as abundant as the latter three

274 -CTD by increasing interaction of the mutant eIF5 with eIF2 by mass action and restoring its defectiv

275 ly with eIF1 and eIF5 and indirectly through eIF5 with the eIF2-GTP-Met-tRNA(i)(Met) ternary complex