ライフサイエンスコーパス: geminin

1 ORCA associates with Cdt1 and its inhibitor, geminin.

2 GMNN, encoding the DNA replication inhibitor geminin.

3 C targets, including the mitotic cyclins and Geminin.

4 and MCM5 co-localization and the absence of geminin.

5 t1, but is independent of the Cdt1 repressor Geminin.

6 iferation-associated genes, such as CDC7 and GEMININ.

7 evels, protein turnover, and Cdt1 binding by geminin.

8 gesting that these are separate functions of geminin.

9 rereplication is enhanced in the absence of geminin.

10 iation is inhibited by the regulatory factor Geminin.

11 re responsible for RB-mediated repression of geminin.

12 (APC/C), and inhibition by a protein called geminin.

13 cell cycle indicator/late cell cycle marker geminin.

14 tability in cells lacking the CDT1 inhibitor Geminin.

15 the level of the subcellular localization of geminin.

16 t possess a functional p53 in the absence of geminin.

17 , one molecule of Cdt1, and two molecules of geminin.

18 Consistent with these results, geminin 5' regulatory sequences and endogenous Xgem resp

19 However, siRNA suppression of geminin (a specific inhibitor of CDT1) arrested prolifer

20 The loss of geminin, a DNA replication inhibitor, causes rereplicati

21 Geminin, a DNA replication inhibitor, plays an important

22 Here we assessed the role for Geminin, a nuclear protein expressed in embryonic cells,

23 sing was associated with the accumulation of geminin, a replication inhibitor.

24 Cs) accumulated in the fetal liver following geminin ablation, while committed progenitors were reduc

25 that overreplication caused by depletion of geminin activated both Chk1 and Chk2, which then phospho

26 These results show that inhibition of geminin activity could be used to selectively kill cance

27 and provide a possible mechanism to modulate Geminin activity.

28 Thus, geminin acts both like a component of the FGF4 signal tr

29 Therefore, here we used a conditional Geminin allele in combination with several Cre-driver li

30 Geminin also affects the development of several differen

31 Geminin also induced apoptosis in both these cell lines.

32 The levels of geminin, an inhibitor of DNA pre-RC, and Emi1, an inhibi

33 Inactivation of Geminin, an inhibitor of origin licensing, leads to re-r

34 Injection of Drosophila Geminin, an inhibitor of replication licensing, prevente

35 ted at an early time point after the loss of Geminin and contributes to checkpoint arrest essential f

36 o accumulate before the licensing inhibitors geminin and cyclin A which are also APC/C substrates.

37 noncancer cells required suppression of both geminin and cyclin A, another cell cycle regulator.

38 of APC/C that results in destabilization of geminin and cyclin A, two proteins shown here to play re

39 is inhibited in S-phase, both by binding to geminin and degradation by proteasomes.

40 ting expression of neural progenitor markers Geminin and Foxd4l1, thereby promoting differentiation.

41 of a bipartite interaction interface between geminin and its cellular targets.

42 xpressed in nascent neuroectoderm, including Geminin and members of the Zic transcription factor fami

43 e mitosis is prevented by the Cdt1 inhibitor geminin and mitotic cyclin activity.

44 trates that functional cooperativity between Geminin and Polycomb contributes to this process.

45 or expression of the neural plate specifiers Geminin and Sox2 and for neural plate formation.

46 etylation at neurodevelopmental genes, while Geminin and Zic1 bind a shared gene subset.

47 Accordingly, we found that Geminin and Zic1 could cooperatively activate the expres

48 Both Geminin and Zic1-associated peaks are enriched for Zic1

49 transcriptional repression, whereas those on geminin and zic2 involve transcriptional activation.

50 Increased FoxD5 induces geminin and zic2, weakly represses sox11 at early gastru

51 Expression levels of cyclin A, Geminin, and Cdt1 were increased in v-K-ras transfectant

52 curin, cyclin A, cyclin B, thymidine kinase, geminin, and many others.

53 , a protein related to the S-phase regulator geminin, and upstream of FOXJ1.

54 Geminin- and Zic1-associated genes exhibit embryonic ner

55 omatin locations in embryonic stem cells and Geminin- and Zic1-associated locations during neural fat

56 In all of these contexts, geminin antagonized the ability of neural basic helix-lo

57 Crucially, geminin antagonizes the chromatin-remodeling protein Brg

58 e coiled-coil domain and a different part of geminin are also required for interaction with HoxA11.

59 Cyclin B1 and geminin are degraded simultaneously during metaphase, wh

60 we show that the protein levels of Cdt1 and geminin are persistently high during the rapid cell cycl

61 30 amino acids within the central domain of geminin are required for both nuclear exclusion and nucl

62 t, IMR90 primary fibroblasts over-expressing geminin arrested in G1 with reduced cyclin E levels and

63 Together, these data support a role for Geminin as a cell intrinsic regulator of neural fate acq

64 This work defines Geminin as an essential regulator of the embryonic trans

65 Here, we identified Geminin-associated chromatin locations in embryonic stem

66 We integrated these data to demonstrate that Geminin associates with and promotes histone acetylation

67 However, maintaining geminin at high levels was not sufficient to prevent ter

68 recombinant and endogenous forms of Xenopus geminin behave differently from one another, such that a

69 We conclude that Cdt1 is regulated both by Geminin binding and by degradation.

70 ccessfully compete with full-length Cdt1 for geminin binding.

71 Here we report that expressing a non-Geminin-binding Cdt1 mutant in Xenopus embryos exactly r

72 to select replication proteins, and map its geminin-binding domain.

73 ssion of the mammalian replication inhibitor geminin blocked replication of the plasmid containing th

74 of Geminin to cell signaling and found that Geminin broadly represses Activin-, FGF- and BMP-mediate

75 omatin is inhibited in extracts treated with geminin but not with p21(CIP1), suggesting that this ste

76 However, functional knockdown of geminin by DeltaCdt1_193-447, which lacks licensing acti

77 ntenance of genomic stability, we eliminated geminin by RNA interference in human cancer cells.

78 Silencing of geminin by RNAi in SD2 cells leads to the cessation of m

79 During the mitotic cell cycle, Geminin can act both as a promoter and inhibitor of init

80 evidence that extracellularly delivered SMoC-geminin can have an antiproliferative effect on human ca

81 We observed that the silencing of geminin causes rapid downregulation of Cdt1/Dup, which m

82 cycle- and stress-regulated proteins such as geminin, cdk2, cdk4, and cytochrome c became apparent at

83 d over-replication, which is counteracted by Geminin co-expression.

84 The properties of the Idas-Geminin complex suggest it as the functional form of Ida

85 Immunoprecipitation of Cdt1 and geminin complexes, together with their cell cycle spatio

86 Geminin contains a typical bipartite nuclear localizatio

87 found that the C-terminal residue Ser184 of Geminin could be phosphorylated by Casein kinase II, res

88 We determined how Geminin deficiency affected histone acetylation at gene

89 cyclin A deficiency is dominant over that of geminin deficiency for cell cycle arrest and overreplica

90 e to the observed partial overreplication in geminin-deficient cells.

91 All cells in geminin-deficient embryos commit to the trophoblast cell

92 Geminin-deficient embryos show a novel and unusual pheno

93 It is not known if the defects in Geminin-deficient organisms are due to overreplication o

94 e Cdt1 mutant in embryos also reproduces the Geminin-deficient phenotype.

95 nscription factors as being upregulated upon geminin deletion, revealing a gene network linked with g

96 Cdc6 degradation in geminin-depleted cells requires Huwe1, the ubiquitin lig

97 find that both Cdt1 and Cdc6 are degraded in geminin-depleted cells.

98 Furthermore, Geminin-depleted oocytes did not replicate their DNA aft

99 eplication in vivo and that the phenotype of Geminin-depleted Xenopus embryos is caused by abnormal C

100 We previously reported that Geminin depletion in Xenopus causes early embryonic leth

101 Geminin depletion or overexpression of Cdt1 or Cdc6 in h

102 exacerbate rereplication when combined with geminin depletion, and this enhanced rereplication occur

103 embryos exactly reproduces the phenotype of geminin depletion.

104 Silencing geminin directly or by depleting the APC/C inhibitor Emi

105 te their DNA after meiosis I indicating that Geminin does not act as an inhibitor of initiation of DN

106 y G1, the surviving population of endogenous geminin does not associate with Cdt1/RLF-B and does not

107 Analysis of cyclin A and geminin double knockout suggests that the effect of cycl

108 driver lines to define an essential role for Geminin during mammalian neural tube (NT) formation and

109 ng on changing interactions between Cdt1 and geminin during the cell cycle, but not their degradation

110 that a significant proportion of endogenous geminin escapes proteolysis upon exit from metaphase.

111 Geminin excision at these stages resulted in strongly di

112 geminin expression is among the earliest markers of dors

113 signaling through the Vent sites restricted geminin expression to the prospective neurectoderm at mi

114 tion factors Cdc6 and Cdtl while suppressing geminin expression, a negative regulator of rereplicatio

115 ent degradation of the replication inhibitor geminin, followed by accumulation of Cdt1, which is requ

116 er, these data demonstrate a requirement for Geminin for NT patterning and neuronal differentiation d

117 Geminin forms a homodimer, with each dimer binding one m

118 Here we report that geminin forms a parallel coiled-coil homodimer with atyp

119 by which suppressed APC/C activity protects geminin from degradation in G1, allowing sustained expre

120 he re-replication is not due to titration of geminin from endogenous Cdt1 and is not accompanied by s

121 In contrast, deleting Geminin from spermatocytes does not disrupt meiosis or t

122 Deleting Geminin from spermatogonia causes complete sterility in

123 However, removal of geminin from Xenopus egg extracts is insufficient to cau

124 Here we show that during meiosis Geminin functions as a stabilizer of Cdt1 promoting its

125 Geminin (Gem) has been proposed to link cell cycle exit

126 and Development, Seo and coworkers show that geminin (Gem), a protein involved in cell cycle control,

127 tive in licensing inhibition compared with a Geminin-Geminin homodimer.

128 in heterodimer binds Cdt1 less strongly than Geminin-Geminin, still with high affinity ( approximatel

129 of Geminin in hematopoiesis by deleting the Geminin gene (Gmnn) from mouse bone marrow cells.

130 In one study, ablation of the geminin gene (Gmnn) in mouse preimplantation embryos res

131 ed two conditional mouse models in which the Geminin gene (Gmnn) is deleted from either spermatogonia

132 (DeltaPIP) expression and a 50% reduction in Geminin gene dose resulted in egg chamber degeneration.

133 utamates and aspartates in the C terminus of Geminin generate an overall charge pattern resembling th

134 mains required for a strong interaction with geminin generated a construct, whose licensing activity

135 The results indicate that geminin has an essential function and that loss of this

136 The biological function of geminin has been difficult to determine because it is no

137 This Idas-Geminin heterodimer binds Cdt1 less strongly than Gemini

138 In contrast to Idas-Geminin heterodimers, Idas homodimers are thermodynamica

139 technique (RNAi) to eliminate the Drosophila geminin homologue from Schneider D2 (SD2) cells.

140 A point mutation in the destruction box of geminin, however, results in a protein that is stabilize

141 Immunohistochemistry and immunoblotting for geminin, however, reveals that the protein is expressed

142 ation, transient overexpression of wild-type geminin in cancer cells in culture did not produce a cel

143 Despite a potential role for Geminin in cell cycle control, we found no evidence of p

144 novel molecular functions for both Cdc6 and geminin in controlling the association of Cdt1 with othe

145 dicating a tissue autonomous requirement for Geminin in developing neuroectoderm.

146 /C)-mediated proteasomal destruction removes geminin in G1.

147 ere, we set out to determine the function of Geminin in hematopoiesis by deleting the Geminin gene (G

148 ovel means of regulating the balance of Cdt1/geminin in human cells, at the level of the subcellular

149 te the stabilization of cyclin B1, cdc6, and geminin in infected cells, its capacity to upregulate th

150 reduce the levels of the mitotic cyclins and Geminin in order to facilitate the relicensing of DNA re

151 nd Cdt1, suggesting that increased levels of geminin in post-G(1) cells titrate Cdt1 away from ORCA.

152 with Cdt1 during mitosis and G(1), and with geminin in post-G(1) cells.

153 ent binding sites regulates transcription of geminin in prospective neurectoderm during gastrulation.

154 e investigated the role of the nucleoprotein geminin in regulating neurogenesis at a mechanistic leve

155 y RNAi leads to the appearance of endogenous geminin in the cytoplasm.

156 We have specifically ablated geminin in the developing murine hematopoietic system an

157 To investigate the role of human geminin in the maintenance of genomic stability, we elim

158 Here, we show that genetic ablation of geminin in the mouse prevents formation of inner cell ma

159 Genetic ablation of geminin in the mouse results in preimplantation embryoni

160 of over-expressing a non-degradable form of geminin in various cell lines.

161 Depletion of Geminin in Xenopus immature oocytes leads to a decrease

162 ation after depletion of the Cdt1 inhibitor, geminin, in an untransformed fibroblast cell line is und

163 n of the DNA replication licensing repressor geminin, in vitro, providing evidence that extracellular

164 red once per cell cycle and was inhibited by Geminin, indicating that the plasmid was properly licens

165 for the cell division cycle and suggest that Geminin inhibition can restrain Dup(DeltaPIP) activity i

166 ensing activity was partially insensitive to geminin inhibition.

167 Geminin inhibits a second round of DNA synthesis during

168 Lastly, Geminin inhibits HBO1 acetylase activity in the context

169 uired for licensing and regions required for geminin interaction.

170 Geminin interacts with a DNA replication initiation fact

171 Geminin interacts with the licensing factor Cdt1 to prev

172 Nondegradable mutants of geminin interfere with DNA replication in succeeding cel

173 Injection of exogenous recombinant Geminin into the depleted oocytes rescues Cdt1 levels de

174 Geminin is a cellular protein that associates with Cdt1

175 Therefore, Geminin is a master regulator of cell-cycle progression

176 Geminin is a nucleoprotein that can directly bind chroma

177 Geminin is a protein involved in both DNA replication an

178 We conclude that Geminin is absolutely required for mitotic proliferation

179 Geminin is also down-regulated in TGCs of wild-type blas

180 Geminin is also required for entry into mitosis, either

181 Geminin is an essential cell-cycle protein that is only

182 Geminin is an important regulator of proliferation and d

183 Geminin is an unstable regulatory protein that affects b

184 Geminin is an unstable regulatory protein that regulates

185 We demonstrate that in human K562 cells geminin is associated with HOXA9 regulatory elements and

186 atin acetylation and accessibility even when Geminin is combined with nuclear extract and chromatin i

187 ts the amount of rereplication observed when Geminin is depleted.

188 We further showed that the interaction with Geminin is homeodomain subclass-selective and Hox paralo

189 Following nuclear assembly, geminin is imported into nuclei and becomes reactivated

190 Our data suggest that geminin is indispensable for fetal hematopoiesis and reg

191 Geminin is known to inhibit Cdt1 function; its depletion

192 Geminin is known to inhibit the replication initiation f

193 Consistently, in Xenopus egg extracts, Idas-Geminin is less active in licensing inhibition compared

194 dt1, and negative regulation of licensing by Geminin is likely to involve inhibition of HBO1 histone

195 In females, Geminin is not required for meiosis, oocyte differentiat

196 ediated degradation, suggesting that loss of geminin is part of the mechanism regulating endoreduplic

197 Geminin is present during the S, G2, and M phases of the

198 Here we show that geminin is present in G1 phase of mouse pluripotent cell

199 Here we show that geminin is regulated transcriptionally by the retinoblas

200 From these results, we conclude that geminin is required for suppressing overreplication in h

201 fibroblast growth factor-4 (FGF4), and that geminin is required to maintain endocycles.

202 blast proliferation and differentiation, and geminin is required to maintain endocycles.

203 ere, we demonstrate that the nuclear protein Geminin is required to restrain commitment and spatially

204 We conclude that Geminin is required to suppress a second round of DNA re

205 Geminin is thought to be involved in licensing replicati

206 The unstable regulatory protein Geminin is thought to be one of the factors that determi

207 The protein Geminin is thought to prevent a second round of DNA repl

208 In comparison to a geminin knockdown 4pX-1 cell line used as DNA re-replica

209 n, pX-expressing 4pX-1 cells, similar to the geminin knockdown 4pX-1 cells, continue to incorporate B

210 Whereas Geminin knockdown does not affect the ability of ES cell

211 Conversely, Geminin knockdown enhances commitment responses to growt

212 Geminin knockout mouse embryos are preimplantation letha

213 Depletion of geminin led to overreplication and the formation of gian

214 n of Cdt1 in mitosis, because decreasing the Geminin levels prevents Cdt1 accumulation and impairs DN

215 embryonic cell cycles nor affects endogenous geminin levels; apparent embryonic lethality is observed

216 Here, we show that geminin, like cyclin B1 and securin, is a bona fide targ

217 stic basis of this phenomenon and found that Geminin maintains a hyperacetylated and open chromatin c

218 Our results suggest that Geminin maintains replication fidelity during the mitoti

219 To examine how Geminin might regulate spermatogenesis, we developed two

220 Comparisons of gene expression in the NT of Geminin mutant versus wild-type siblings at embryonic da

221 (PCNA) or with cyclin-Cdk2 and inhibited by geminin once cells are in S-phase, presumably to prevent

222 Two regions of Cdt1 interact with geminin: one at the N-terminus, and one in the centre of

223 reventing DNA replication by the addition of geminin or aphidicolin disturbs the formation of topo II

224 e-RC assembly, either by addition of Xenopus geminin or by depletion of XlMcm proteins, augmented ORC

225 For example, we did not identify geminin or RNASEH1 genes in plants.

226 ' sequence domains were also conserved among geminin orthologs.

227 Geminin overexpression during embryonic development indu

228 Conversely, Geminin overexpression promotes neural gene expression,

229 used microarray analyses to demonstrate that Geminin overexpression represses many genes associated w

230 Geminin plays a crucial role in inhibiting licensing in

231 A small protein called geminin plays an important role in this down-regulation

232 We show that Geminin preferentially forms stable coiled-coil heterodi

233 As an inhibitor, Geminin prevents Cdt1 from loading the mini-chromosome m

234 bryos resulted in apoptosis, suggesting that geminin prevents DNA re-replication, whereas in another

235 In multicellular eukaryotes, geminin prevents overreplication of DNA in proliferating

236 Furthermore, geminin promoted a bivalent chromatin state, characteriz

237 itical regulatory cis-acting elements in the geminin promoter indicated that intragenic E2F sites dow

238 The direct analysis of the endogenous geminin promoter revealed that these intragenic E2F site

239 orter constructs containing fragments of the geminin promoter were generated.

240 ite rapid Cdt1 protein turnover in G2 phase, Geminin promotes Cdt1 accumulation by increasing its RNA

241 irected at mesodermal genes demonstrate that Geminin promotes Polycomb binding and Polycomb-mediated

242 herefore, these data support a model whereby geminin promotes the neuronal precursor cell state by mo

243 Interestingly, recombinant Geminin protein also rapidly alters chromatin acetylatio

244 The geminin protein is a critical regulator of DNA replicati

245 Geminin protein levels, which are low in G(0)/G(1) and i

246 Cdt1 activity is inhibited by the geminin protein, and we provide evidence that the mechan

247 the structural and functional domains of the geminin protein, we generated over 40 missense and delet

248 truction box sequence near the 5' end of the geminin protein.

249 during S phase and inhibition of Cdt1 by the geminin protein.

250 This reactivated geminin provides the major nucleoplasmic inhibitor of or

251 ty is regulated by periodic interaction with geminin rather than its proteolysis.

252 used as DNA re-replication control, the Cdt1/geminin ratio is greater in 4pX-1 cells expressing pX, i

253 Moreover, silencing geminin reduced recruitment of the PRC2 component SUZ12

254 Geminin regulates the extent of DNA replication and is t

255 These data led us to postulate that Geminin regulates the relative production of erythrocyte

256 phoblast giant cells (TGCs), suggesting that geminin regulates trophoblast specification and differen

257 fibroblasts have enhanced the expression of geminin relative to wild type mouse embryonic fibroblast

258 s that had similar activities and found that Geminin represses commitment independent of Oct 4 orthol

259 Overexpression of geminin results in the loss of interaction between ORCA

260 of Rb in mouse adult fibroblasts deregulated geminin RNA and protein levels.

261 These data demonstrate that Geminin's activity contributes to mammalian neural cell

262 We identified several missense mutations in geminin's Cdt1 binding domain that were deficient in the

263 Geminin's Cdt1-binding domain lies immediately adjacent

264 e 32-cell stage, precluding in vivo study of Geminin's role in neural development.

265 We find that geminin self-associates through the coiled-coil domain t

266 tazoans, both Cdt1 and its natural inhibitor geminin show reciprocal fluctuations in their protein le

267 the homology regions of Idas in complex with Geminin showed a tight head-to-head heterodimeric coiled

268 iate to erythrocytes and megakaryocytes upon geminin silencing.

269 Overexpression of ectopic geminin slows down, but neither arrests early embryonic

270 foxD5's effects on geminin, sox11 and zic2 occur at the onset of gastrulati

271 geminin, sox11 and zic2, each of which is up-regulated d

272 Xiro1-3 at the onset of gastrulation, and of geminin, sox3 and zic2, which are maternally expressed,

273 As a promoter, Geminin stabilizes Cdt1 and facilitates its accumulation

274 cytes rescues Cdt1 levels demonstrating that Geminin stabilizes Cdt1 during meiosis and after fertili

275 letion, revealing a gene network linked with geminin that controls fetal hematopoiesis.

276 Recombinant geminin that is added to Xenopus egg extracts is efficie

277 Only the central region binds geminin tightly enough to successfully compete with full

278 Moreover, FGF4 deprivation of TSCs reduces geminin to a basal level that is required for maintainin

279 We characterized the relationship of Geminin to cell signaling and found that Geminin broadly

280 targets Cdt1 and that acts redundantly with geminin to inactivate Cdt1 in S phase.

281 ycle progression, but also functions through geminin to prevent DHFR amplification and protect genomi

282 erphase to stabilize the mitotic cyclins and geminin to promote mitosis and prevent rereplication.

283 tain mechanistic insight into the ability of geminin to regulate transcription, we examined Hoxa9 as

284 Cdt1 overexpression targets geminin to the nucleus, while reducing Cdt1 levels by RN

285 Together, these data link the expression of geminin to the RB/E2F pathway and represent the first pr

286 he activation of RB led to the repression of geminin transcription.

287 tigens (eg, cyclins D2 and E2, cdc2/p34, and geminin), transcription factors (eg, homeobox B7 and isl

288 When Geminin was deleted specifically in the spinal NT, both

289 In this study, geminin was eliminated from developing Xenopus embryos b

290 e observed, but neither defect occurred when Geminin was excised in paraxial mesenchyme, indicating a

291 Uptake of SMoC-geminin was inhibited at 4 degrees C and by chlorpromazi

292 Geminin was required in the NT within a critical develop

293 Geminin was sufficient to prevent the occurrence of mult

294 One inhibitor of pre-RC assembly, geminin, was discovered in Xenopus, and it binds and ina

295 We show here that human geminin, when expressed in human cells in culture under

296 y regulating the level of CDT1 activity with geminin, whereas noncancer cells contain additional safe

297 The addition of geminin, which blocks pre-RC formation, prevents the loa

298 The N-terminal 30 amino acids of geminin, which contain its destruction box, are essentia

299 in in complex with the cell-cycle regulator, Geminin, which inhibits Hox transcriptional activity and

300 characterized the functional relationship of Geminin with transcription factors that had similar acti