ライフサイエンスコーパス: heterocyst

1 over the 24 h required to form a functional heterocyst.

2 downstream events required for a functional heterocyst.

3 cell of a filament to differentiation into a heterocyst.

4 o maintain a microaerobic environment in the heterocyst.

5 ament terminally differentiate to nongrowing heterocysts.

6 alcein transfer between vegetative cells and heterocysts.

7 ecialized cells for nitrogen fixation called heterocysts.

8 on but are not essential for upregulation in heterocysts.

9 in four mutant backgrounds that overproduce heterocysts.

10 ccurred primarily in cells that would become heterocysts.

11 a hetR mutant allows the differentiation of heterocysts.

12 erocysts but a decreased percentage of total heterocysts.

13 oming considerably faster than exchange with heterocysts.

14 the presence of cyanophycin polar nodules in heterocysts.

15 fferentiation only in cells that will become heterocysts.

16 y in vegetative cells, as well as developing heterocysts.

17 ereas N(2) fixation is confined to microoxic heterocysts.

18 e filament into nitrogen-fixing cells called heterocysts.

19 PCC 7120 differentiate into nitrogen-fixing heterocysts.

20 getative cells into specialized cells called heterocysts.

21 ssed only in the vegetative cells but not in heterocysts.

22 cells to become specialized nitrogen-fixing heterocysts.

23 e from oxygen in differentiated cells called heterocysts.

24 e N2 fixation in differentiated cells called heterocysts.

25 ular pattern of nitrogen-fixing cells called heterocysts.

26 d that this gene is expressed exclusively in heterocysts.

27 xation and maintaining a low oxygen level in heterocysts.

28 expressed specifically in proheterocysts and heterocysts.

29 the HetR protein specifically accumulates in heterocysts.

30 ed differentiation of N2-fixing cells called heterocysts.

31 y, vegetative cells transfer fixed carbon to heterocysts.

32 eat or EDTA, but was able to form functional heterocysts.

33 transport of sugar from vegetative cells to heterocysts.

34 ene expression is suggested to take place in heterocysts.

35 nic photosynthesis and the dinitrogen-fixing heterocysts.

36 n by inhibiting the formation of consecutive heterocysts.

37 ophycinase are present at high levels in the heterocysts.

38 tic vegetative cells and the nitrogen-fixing heterocysts.

39 pression in hormogonia, and no expression in heterocysts.

40 l envelope is not required for patterning of heterocysts.

41 ease in the vegetative cell interval between heterocysts.

42 a fixes nitrogen in specialized cells called heterocysts.

43 lled sigF) is upregulated in differentiating heterocysts 16 h after nitrogen step-down.

44 um Anabaena sp. strain PCC 7120 forms single heterocysts about every 10 to 15 vegetative cells along

45 N-fixing heterocysts accumulate an insoluble polymer containing a

46 d type, an asr1734 knockout mutant formed 5% heterocysts after a nitrogen shift from ammonium to nitr

47 ically in differentiating proheterocysts and heterocysts after nitrogen step-down.

48 along the filament but differentiate excess heterocysts after several days in the absence of combine

49 PatA is necessary for proper patterning of heterocysts along filaments.

50 nd even pattern formation, as the spacing of heterocysts along the filament is non-random.

51 s that regulate the frequency and pattern of heterocysts along vegetative cell filaments.

52 ually long vegetative cell intervals between heterocysts also contained intervals of normal length.

53 lance of cytosolic redox state in Deltaflv3B heterocysts also has a pronounced influence on the amoun

54 to be differentially transcribed during the heterocyst and hormogonium time courses, respectively, a

55 ift from ammonium to nitrate, and formed 15% heterocysts and a weak Mch phenotype after step-down to

56 Transcription of sigG increased in heterocysts and akinetes, and after EDTA treatment.

57 The xisC mutant forms heterocysts and grows diazotrophically, but unlike the w

58 A hetF deletion strain lacked heterocysts and had aberrant cell morphology.

59 are true multicellular prokaryotes, in which heterocysts and vegetative cells have complementary meta

60 The septa between heterocysts and vegetative cells, which are narrow in wi

61 utative metabolic exchange reactions between heterocysts and vegetative cells.

62 oglycan between vegetative cells and between heterocysts and vegetative cells.

63 xopolysaccharide and glycolipids specific to heterocysts, and nitrogenase activity was present under

64 hologies: motile hormogonia, nitrogen-fixing heterocysts, and spore-like akinetes.

65 s responsible for light-induced O2 uptake in heterocysts, and that the absence of the Flv3B protein s

66 percentage of cells that differentiate into heterocysts appears to be a function of time when a sour

67 Nitrogen-fixing heterocysts are arranged in a periodic pattern on filame

68 cyanobacterium Anabaena sp. strain PCC 7120, heterocysts are formed in the absence of combined nitrog

69 Heterocysts are metabolically and structurally specializ

70 Heterocysts are specialized cells required for aerobic f

71 Heterocysts are terminally differentiated cells that fix

72 The preponderance of even intervals between heterocysts arises naturally as a result of the interpla

73 cyanobacteria differentiate nitrogen-fixing heterocysts at regular intervals along unbranched filame

74 to gas exchange: N(2) and O(2) diffuse into heterocysts at similar rates, which ensures that concent

75 these genes should enhance understanding of heterocyst biology.

76 n produced an increased number of contiguous heterocysts but a decreased percentage of total heterocy

77 e are expressed in both vegetative cells and heterocysts but do not seem to have an essential role in

78 mutant forms morphologically distinguishable heterocysts but is Fox(-), incapable of nitrogen fixatio

79 ly displayed the wild-type pattern of single heterocysts but, 48 h after the induction of heterocyst

80 odic pattern of nitrogen-fixing cells called heterocysts by the filamentous cyanobacterium Anabaena s

81 erentiation of nitrogen-fixing cells, called heterocysts, by the cyanobacterium Anabaena sp. strain P

82 These heterocysts can fix nitrogen under anaerobic conditions

83 rain PCC 7120 differentiates nitrogen-fixing heterocyst cells in a periodic pattern.

84 Heterocysts, cells specialized for nitrogen fixation in

85 ripheries and in the polar regions of mature heterocysts, coinciding with the location of the thylako

86 that share a functional domain and modulate heterocyst commitment: hetP (alr2818), asl1930, alr2902,

87 Heterocysts conspicuously accumulate polar granules made

88 A steady-state N(2)-grown (heterocyst-containing) culture showed differential trans

89 A hetL-null mutant showed normal heterocyst development and diazotrophic growth, which co

90 The devH gene is induced during heterocyst development and encodes a product with charac

91 ow that the sigE gene is required for normal heterocyst development and normal expression levels of s

92 hetR and hetC mutations that block heterocyst development are epistatic to hetL overexpress

93 ble petE promoter did not completely inhibit heterocyst development but caused a 24-h delay in hetero

94 ightly reduced expression after induction of heterocyst development by nitrogen stepdown.

95 etR and patS, two critical regulators of the heterocyst development cascade, are normal for patB muta

96 indicating that the RGSGR motif can inhibit heterocyst development in a variety of contexts.

97 etL overexpression allowed the initiation of heterocyst development in an ntcA-null mutant, but diffe

98 HetR is an essential regulator of heterocyst development in cyanobacteria.

99 HetR is an essential regulator of heterocyst development in cyanobacteria.

100 Overexpression of asr1734 inhibited heterocyst development in several strains including the

101 er gene to determine their expression during heterocyst development in the cyanobacterium Anabaena (N

102 egulation of eight sigma factor genes during heterocyst development in the cyanobacterium Anabaena sp

103 gene, hetF, was identified as essential for heterocyst development in the filamentous cyanobacterium

104 n of pknE from its native promoter inhibited heterocyst development in the wild type and in four muta

105 Recent progress in understanding heterocyst development in these simple multicellular org

106 Heterocyst development is controlled by the availability

107 baena (Nostoc) sp. strain PCC 7120 inhibited heterocyst development when present in extra copies.

108 Overexpression of sigE caused accelerated heterocyst development, an increased heterocyst frequenc

109 bly of transcription components critical for heterocyst development.

110 one of these genes, all2874, caused abnormal heterocyst development.

111 sion may be inhibited by products related to heterocyst development.

112 ognized as a key player in the regulation of heterocyst development.

113 , and there was little overlap with putative heterocyst developmental genes.

114 attern in the hetRR223W mutant revealed that heterocysts differentiate essentially randomly along fil

115 ocyst development but caused a 24-h delay in heterocyst differentiation and cell bleaching 4 to 5 day

116 gulated genes were predicted from studies of heterocyst differentiation and N(2) fixation; other gene

117 delayed and reduced transcript levels during heterocyst differentiation in a sigE mutant background.

118 biochemical regulation of the progression of heterocyst differentiation in Anabaena sp. strain PCC 71

119 HetR is the master regulator of heterocyst differentiation in the filamentous cyanobacte

120 Heterocyst differentiation involves extensive biochemica

121 How heterocyst differentiation is regulated, once particular

122 - phenotype, were found to have no effect on heterocyst differentiation or patterning when the corres

123 t reduced the proportion of cells undergoing heterocyst differentiation to less than 2%.

124 R increases heterocyst frequency and induces heterocyst differentiation under fully repressing condit

125 ive oxidoreductase that is known to suppress heterocyst differentiation when present on a multicopy p

126 ions that dramatically reduced the amount of heterocyst differentiation when the mutant allele was pr

127 rogress both in understanding the control of heterocyst differentiation, and also in understanding th

128 ty, normal intercellular molecular exchange, heterocyst differentiation, and diazotrophic growth.

129 competency of a vegetative cell to initiate heterocyst differentiation, and the cellular concentrati

130 The master regulator of heterocyst differentiation, HetR, is necessary for both

131 by cyanobacteria relies on two inhibitors of heterocyst differentiation, PatS and HetN, in a manner c

132 Patterning requires two inhibitors of heterocyst differentiation, PatS and HetN, which work at

133 During the late stages of heterocyst differentiation, three DNA elements, each emb

134 patA, which encodes a positive effector of heterocyst differentiation, was up-regulated in all muta

135 acts in the regulatory cascade that controls heterocyst differentiation, we replaced the native chrom

136 tR in the regulatory network responsible for heterocyst differentiation.

137 which is considered the master regulator of heterocyst differentiation.

138 own to partially bypass the need for hetR in heterocyst differentiation.

139 rcellular transfer of regulatory signals for heterocyst differentiation.

140 ced >20-fold in the middle to late stages of heterocyst differentiation.

141 and is an integral part of the induction of heterocyst differentiation.

142 oc punctiforme are required for synthesis of heterocyst envelope glycolipids.

143 evelopmental regulation of biosynthesis of a heterocyst envelope polysaccharide.

144 a gene that plays a role in the synthesis of heterocyst envelope polysaccharide.

145 h the absence of the glycolipid layer of the heterocyst envelope.

146 Heterocyst envelopes of mutants affected in any of those

147 These heterocysts form a quasiregular pattern in the filament,

148 ns resulted in a Het- phenotype, compared to heterocyst formation among approximately 25% of cells wi

149 An H69Y substitution resulted in heterocyst formation among less than 0.1% of cells, and

150 fferentiation processes such as sporulation, heterocyst formation and fruiting body development.

151 P(rbcL) promoters, patS5 to patS8 inhibited heterocyst formation but patS4 did not.

152 formation in the wild type, did not suppress heterocyst formation in a hetL overexpression strain, in

153 Extracopy hetL allowed heterocyst formation in a patS overexpression strain.

154 last 5 amino acids of PatS, which suppresses heterocyst formation in the wild type, did not suppress

155 Heterocyst formation is subject to complex regulation, w

156 heterocysts but, 48 h after the induction of heterocyst formation, a pattern of multiple contiguous h

157 r the control of the petE promoter inhibited heterocyst formation, indicating that the RGSGR motif ca

158 ession of the hetY gene partially suppressed heterocyst formation, resulting in an abnormal heterocys

159 od of nitrogen deprivation, which results in heterocyst formation.

160 ith a C-terminal hexahistidine tag inhibited heterocyst formation.

161 protein GFP-PatS-5 fusion protein inhibited heterocyst formation.

162 but do not seem to have an essential role in heterocyst formation.

163 lator NtcA is required for the initiation of heterocyst formation.

164 Overexpression of the patS gene suppresses heterocyst formation.

165 Within the heterocyst-forming clades, some strains, such as the Nos

166 Filamentous heterocyst-forming cyanobacteria are a beautiful example

167 Heterocyst-forming cyanobacteria are multicellular organ

168 Filamentous, N2 -fixing, heterocyst-forming cyanobacteria grow as chains of cells

169 Photoreduction of dinitrogen by heterocyst-forming cyanobacteria is of great importance

170 a feature that is conserved among all known heterocyst-forming cyanobacteria sequenced to date.

171 nces shows that TS-821 is closely related to heterocyst-forming cyanobacteria, some of which also hav

172 ique multicellular system represented by the heterocyst-forming cyanobacteria.

173 ros) is more similar to those of free-living heterocyst-forming cyanobacteria.

174 e TolC-like protein HgdD of the filamentous, heterocyst-forming cyanobacterium Anabaena sp. PCC 7120

175 the TolC-like homologue of the filamentous, heterocyst-forming cyanobacterium Anabaena sp. PCC 7120,

176 The genome of the heterocyst-forming cyanobacterium Anabaena sp. strain PC

177 The filamentous, heterocyst-forming cyanobacterium Anabaena sp. strain PC

178 ncoding isoaspartyl dipeptidase in the model heterocyst-forming cyanobacterium Anabaena sp. strain PC

179 Heterocyst-forming filamentous cyanobacteria are true mu

180 ATCC 29133 leads to a threefold increase in heterocyst frequency and a fourfold decrease in the vege

181 ow that ectopic expression of hetR increases heterocyst frequency and induces heterocyst differentiat

182 er high-light growth conditions, the initial heterocyst frequency and pattern for the all2874 mutant

183 2874 mutant showed a pronounced reduction in heterocyst frequency during diazotrophic growth and redu

184 porter, which indicates that the decrease in heterocyst frequency is due to an early block in differe

185 n had shorter filaments with slightly higher heterocyst frequency than did the wild type.

186 874 is required for the normal regulation of heterocyst frequency under high-light growth conditions.

187 lerated heterocyst development, an increased heterocyst frequency, and premature expression of GFP fl

188 up to 50 mM, showing increased cell size and heterocyst frequency.

189 cyanobacterium Anabaena sp. PCC 7120, termed heterocyst glycolipid deposition protein D (HgdD), is in

190 genes in the mutant is greatly reduced, and heterocyst glycolipids are undetectable.

191 The heterocyst has an envelope that provides a barrier to ga

192 true branches, and cell differentiation into heterocysts, hormogonia and necridia.

193 tative cells into three distinct cell types, heterocysts, hormogonia, and akinetes, in response to di

194 na sp. strain PCC 7120 forms nitrogen-fixing heterocysts in a periodic pattern in response to combine

195 e required for the development of functional heterocysts in Anabaena and Nostoc, respectively.

196 olved in the differentiation and function of heterocysts in Anabaena sp. strain PCC 7120 have been id

197 when overproduced and altered the pattern of heterocysts in filaments with an otherwise wild-type gen

198 well as for the relative lack of intercalary heterocysts in patA mutants.

199 lamentous cyanobacterium that differentiates heterocysts in response to deprivation of combined nitro

200 e hetR gene is seen in developing and mature heterocysts in response to fixed nitrogen limitation.

201 ulates the differentiation and patterning of heterocysts in the filamentous cyanobacterium Anabaena s

202 g nitrogen step-down, many intervals between heterocysts increased to as many as 200 vegetative cells

203 ain PCC 7120 RGSGR-encoding genes might show heterocyst inhibition activity.

204 yl-arginine produced from cyanophycin in the heterocysts is transferred intercellularly to be hydroly

205 the 10 to 20 vegetative cells that separate heterocysts is unknown.

206 the Mo nitrogenase that is expressed only in heterocysts, is cotranscribed with nifD1 and nifK1, whic

207 t, as an association of vegetative cells and heterocysts, is postulated to depend on metabolic exchan

208 functional genes were upregulated, while the heterocyst master regulator hetR was downregulated.

209 ractions between HetP, its homologs, and the heterocyst master regulator, HetR, were assessed, and in

210 ed expression of hepC and hepA and prevented heterocyst maturation and aerobic fixation of N(2).

211 tion of hetY increased the time required for heterocyst maturation and caused defects in heterocyst m

212 hepK, hepN, henR, and hepS are required for heterocyst maturation in Anabaena sp. strain PCC 7120.

213 ed as being required specifically for normal heterocyst maturation.

214 that HetN anchored to thylakoid membranes in heterocysts may serve a function besides that of generat

215 ese factors produces the multiple contiguous heterocyst (Mch) phenotype.

216 ularly spaced single and multiple contiguous heterocysts (Mch phenotype) in combined nitrogen-free me

217 nd two strains that form multiple contiguous heterocysts (Mch phenotype): a PatS null mutant and a he

218 nabaena PCC 7120 induced multiple-contiguous heterocysts (Mch) in nitrate-containing medium.

219 heterocyst maturation and caused defects in heterocyst morphology.

220 Their heterocysts must have a glycolipid envelope layer that l

221 he products of nitrogen fixation supplied by heterocysts, must also play a role in late long-range in

222 close to the cytoplasmic membrane and in the heterocyst neck, using immunogold labeling with antibody

223 h alr2835 (hepA) and alr2834 (hepC) mutants, heterocysts of Anabaena sp. strain PCC 7120, a filamento

224 Heterocysts of both hepK Anabaena and devRA Anabaena lac

225 The subcellular localization in heterocysts of fluorescence resulting from the fusion of

226 Heterocysts of patA and patL Anabaena sp. form nearly ex

227 Heterocysts of the nine mutants were found to lack an en

228 e transition from vegetative cells to either heterocysts or hormogonia resulted in rapid and sustaine

229 between cells bound for differentiation into heterocysts or hormogonia, yet the two paths are disting

230 essary for the formation of most intercalary heterocysts, or hetF resulted in an increase in HetR pro

231 The PatS and HetN factors contribute to the heterocyst pattern by inhibiting the formation of consec

232 PatS is proposed to control the heterocyst pattern by lateral inhibition.

233 of hetR in the genetic network that governs heterocyst pattern formation and differentiation.

234 a small peptide that is required for normal heterocyst pattern formation in the cyanobacterium Anaba

235 We use these data to build a theory on heterocyst pattern formation, for which both genetic reg

236 s insensitive to the major signals governing heterocyst pattern formation.

237 sent further analysis of patS expression and heterocyst pattern formation.

238 ance of heterocyst spacing after the initial heterocyst pattern has been established, but ectopic exp

239 Analysis of the heterocyst pattern in the hetRR223W mutant revealed that

240 e in the signaling pathway that controls the heterocyst pattern.

241 terocyst formation, resulting in an abnormal heterocyst pattern.

242 ixation are the main signals determining the heterocyst pattern.

243 lication of the activator-inhibitor model to heterocyst patterning and, more generally, the formation

244 Inactivation of another heterocyst patterning gene, patA, is epistatic to inacti

245 o acid motif to regulate different stages of heterocyst patterning.

246 ecessary for the delayed multiple-contiguous-heterocyst phenotype observed in hetN mutants as well as

247 formation, a pattern of multiple contiguous heterocysts predominated.

248 Cyanobacteria that form akinetes as well as heterocysts present a rare opportunity to investigate th

249 Here we show that the periodic pattern of heterocysts produced by cyanobacteria relies on two inhi

250 ide the heterocysts with reduced carbon, and heterocysts provide the vegetative cells with fixed nitr

251 cating that HetL overexpression is affecting heterocyst regulation downstream of PatS production.

252 Successive transcription of heterocyst regulatory, structural, and functional genes

253 Consistently, isolated heterocysts released substantial amounts of beta-asparty

254 o anaerobic factories for nitrogen fixation (heterocysts), requires the transport of amino acids from

255 o establish and maintain a pattern of single heterocysts separated by approximately 10 undifferentiat

256 N is normally involved in the maintenance of heterocyst spacing after the initial heterocyst pattern

257 atB mutants have a normal initial pattern of heterocyst spacing along the filament but differentiate

258 understanding of the mechanism that controls heterocyst spacing in filamentous cyanobacteria.

259 otein that is one of the factors controlling heterocyst spacing.

260 most abundant cyanobacterial symbionts form heterocysts (specialized cells for N(2) fixation) and pr

261 side the nifE1 gene, and both promoters were heterocyst specific.

262 D)-gfp reporter construct that showed strong heterocyst-specific expression.

263 A, and Flv4 present in vegetative cells, two heterocyst-specific flavodiiron proteins, Flv1B and Flv3

264 ment and normal expression levels of several heterocyst-specific genes.

265 ption factor required for expression of many heterocyst-specific genes.

266 s, encoding dinitrogenase reductases for the heterocyst-specific Mo-nitrogenase and the alternative V

267 The heterocyst-specific nitrogenase encoded by the large nif

268 e are able to compensate for the loss of the heterocyst-specific oxidase in providing ATP for nitroge

269 f coxAII, the gene encoding subunit I of the heterocyst-specific oxidase, grows normally in the absen

270 tually exclusive cell types: nitrogen-fixing heterocysts, spore-like akinetes, and motile hormogomium

271 The differentiation of heterocysts (steady state, N(2) grown), akinetes, and ho

272 During hormogonium differentiation, some heterocyst structural and functional genes were upregula

273 s of Anabaena sp. PCC 7120 that can overcome heterocyst suppression caused by overexpression of the p

274 is present at significantly lower levels in heterocysts than in vegetative cells.

275 spatial pattern that mimicked the pattern of heterocysts that emerged.

276 tide intercellular signal made by developing heterocysts that prevents neighboring cells from differe

277 ly produced cells morphologically similar to heterocysts that produced exopolysaccharide and glycolip

278 . PCC 7120 differentiates specialized cells, heterocysts, that fix atmospheric nitrogen and transfer

279 e activator, HetR, were observed adjacent to heterocysts, the natural source of PatS and HetN, as wel

280 structural changes that collectively permit heterocysts to assimilate N2 aerobically and supply the

281 ion of vegetative cells into nitrogen-fixing heterocysts to establish and maintain a pattern of singl

282 rginine is a principal nitrogen carrier from heterocysts to vegetative cells in Anabaena.

283 , requires the transport of amino acids from heterocysts to vegetative cells, and reciprocally, the t

284 , the vnfH gene was expressed exclusively in heterocysts under either aerobic or anaerobic growth con

285 lowly and differentiates multiple contiguous heterocysts under nitrogen-deficient conditions.

286 at expresses the uptake hydrogenase HupSL in heterocysts under nitrogen-fixing conditions.

287 mmonium can be induced to form hormogonia or heterocysts upon removal of the combined nitrogen.

288 th conditions in differentiated cells called heterocysts using either a Mo nitrogenase or a V nitroge

289 3 fixes nitrogen in specialized cells called heterocysts using either a Mo-nitrogenase or a V-nitroge

290 the number of cells that differentiated into heterocysts were affected.

291 t vegetative cells from differentiating into heterocysts when a source of ammonia is not present.

292 nt differentiation of a wild-type pattern of heterocysts when filaments of the mutant were transferre

293 rms of N, grow and divide, and differentiate heterocysts when fixed N is depleted.

294 forms a periodic pattern of nitrogen-fixing heterocysts when grown in the absence of combined nitrog

295 tosynthetic O2 uptake has a distinct role in heterocysts which cannot be substituted by respiratory O

296 enus Anabaena, some cells differentiate into heterocysts, which lose the possibility to divide but ar

297 make nitrogenase under aerobic conditions in heterocysts while the cnfR2 mutant was unable to make ni

298 CnfR1 activates nifB1 expression in heterocysts, while CnfR2 activates nifB2 expression.

299 Vegetative cells provide the heterocysts with reduced carbon, and heterocysts provide

300 y is through the terminal pores that connect heterocysts with vegetative cells.