ライフサイエンスコーパス: PGHS-2

1 taglandin endoperoxide H(2) synthase enzyme (PGHS-2).

2 y of prostaglandin H(2) isoforms (PGHS-1 and PGHS-2).

3 ned than the corresponding radical in native PGHS-2.

4 darbufelone competes directly for binding to PGHS-2.

5 ed by determining the reduction potential of PGHS-2.

6 substrate specificity for PGHS-1 but not for PGHS-2.

7 GHS-2) have COX activities similar to native PGHS-2.

8 the extent of endocannabinoid oxygenation by PGHS-2.

9 ecomes uncoupled from the tyrosyl radical in PGHS-2.

10 isoform of prostaglandin H synthase (PGHS), PGHS-2.

11 ctive inhibitors interacting with PGHS-1 and PGHS-2.

12 h an EPR spectrum similar to that found with PGHS-2.

13 heme moiety to be 20 A in PGHS-1 and 18 A in PGHS-2.

14 bodies partially attenuates the induction of PGHS-2.

15 m termed PGHS-1 and an inducible form termed PGHS-2.

16 ation of AA oxygenation by cyanide-inhibited PGHS-2.

17 diary substance regulating the expression of PGHS-2.

18 to be indistinguishable from that in control PGHS-2.

19 f the rates of formation of PGH(2) by native PGHS-2.

20 ximally acetylates one monomer of human (hu) PGHS-2.

21 , conversion was less efficient than that by PGHS-2.

22 tabolism-dependent, selective inactivator of PGHS-2.

23 trates differentially regulate PGHS-1 versus PGHS-2.

24 rbiprofen to about the same extent as native PGHS-2.

25 tivity observed in aspirin-treated wild-type PGHS-2.

26 singlet EPR signal similar to that of native PGHS-2.

27 tion of monocyte prostaglandin H synthase-2 (PGHS-2), a pivotal enzyme in the PGE2-cAMP dependent pat

28 Native/R120Q PGHS-2, a heterodimer in which both subunits can oxygena

29 Native/G533A PGHS-2, a heterodimer with a COX-inactive subunit, had t

30 lls, the FA tone, is a key factor regulating PGHS-2 activity and its responses to COX inhibitors.

31 Plots of PGHS-2 activity vs preincubation time at various darbufe

32 S, suggesting a dependence of this enzyme on PGHS-2 activity.

33 removal of Tyr348-Tyr385 hydrogen bonding in PGHS-2 allows greater conformational flexibility in the

34 Prostaglandin endoperoxide H synthase-2 (PGHS-2), also called cyclooxygenase-2 (COX-2), converts

35 Prostaglandin endoperoxide H synthase-2 (PGHS-2), also known as cyclooxygenase-2 (COX-2), is a se

36 endoperoxide H synthases-1 and 2 (PGHS-1 and PGHS-2; also cyclooxygenases-1 and 2, COX-1 and COX-2) c

37 The inclusion of PGHS-2 among the early response genes induced in leukocy

38 yl radicals in lipoxygenase catalysis by ASA-PGHS-2 and also indicate that the AA radical in ASA-PGHS

39 m a wide doublet to a wide singlet in native PGHS-2 and for formation of a narrow singlet in complexe

40 We found that the induction of PGHS-2 and generation of PGE2 in these cells by IFN-gamm

41 2) that has 1.7-1.8 times the Vmax of native PGHS-2 and is relatively insensitive to activation by FA

42 ion resulted in increased IL-1beta-dependent PGHS-2 and microsomal PGE(2) synthase levels.

43 e activity, also suppressed the induction of PGHS-2 and MMPs.

44 cate that the peroxide-generated radicals in PGHS-2 and MnPGHS-1 can each serve as immediate oxidants

45 PR data for the AA-derived radical formed by PGHS-2 and MnPGHS-1 could be accounted for by a planar p

46 have examined the ability of the radicals in PGHS-2 and MnPGHS-1 to oxidize AA, using single-turnover

47 These results indicate that the induction of PGHS-2 and mPGES by IL-1beta underlies robust PGE(2) pro

48 (IL)-1beta treatment elicits high levels of PGHS-2 and mPGES expression.

49 y, we examined the concomitant expression of PGHS-2 and NOS II as well as the production of prostagla

50 However, the apparent link between PGHS-2 and NOS II has not been thoroughly investigated i

51 glandin endoperoxide synthase-1 (PGHS-1) and PGHS-2 and purified the recombinant enzymes using buffer

52 cal formation in prostaglandin H synthase-2 (PGHS-2) and in PGHS-1 reconstituted with mangano protopo

53 rrow singlet EPR (25-26 G in PGHS-1; 21 G in PGHS-2), and the same line shapes persisted throughout t

54 ence for independent signaling by PGHS-1 and PGHS-2, and the complex mechanisms for regulation of PGH

55 imiting enzymes for prostaglandin formation, PGHS-2, and the production of PGE2 and PGF2alpha.

56 g that the hydroperoxide-induced radicals in PGHS-2 are also tyrosyl radicals.

57 PGHS-1 and PGHS-2 are conformational heterodimers, each composed of

58 s of helical residues 119-122 of S121P/S121P PGHS-2 are displaced from their normal positions.

59 Here we demonstrate that mPGES and PGHS-2 are expressed at very low levels in untreated hum

60 enation of arachidonic acid (AA) and 2-AG by PGHS-2 are very similar, but the sensitivities of the tw

61 uction of PGE2 reflected the upregulation of PGHS-2 as indicated by enhanced expression of PGHS-2 RNA

62 In contrast, aspirin-treated PGHS-2 (ASA-PGHS-2) no longer forms prostaglandins but r

63 These results suggest that native PGHS-2 assumes a reasonably stable, asymmetric Eallo/Eca

64 Darbufelone quenches the fluorescence of PGHS-2 at 325 nm (lambda(ex) = 280 nm) with K(d) = 0.98

65 tic acid, an efficacious stimulator of human PGHS-2, binds only E(allo) in palmitic acid/murine PGHS-

66 A selective inhibitor of PGHS-2 blocked PGE2 formation by cells incubated with ta

67 Thus, the structural stability of PGHS-2, both in the active site regions and in the subun

68 d bind Eallo of PGHSs stimulating human (hu) PGHS-2 but inhibiting huPGHS-1.

69 iors of PGHSs may account for the ability of PGHS-2 but not PGHS-1 to efficiently oxygenate AA in int

70 ithelial cell line, expresses high levels of PGHS-2 but surprisingly low levels of PGE(2) when compar

71 poxygenase catalysis and that acetylation of PGHS-2 by ASA favors arachidonate binding in an altered

72 utyl phenols such as darbufelone may inhibit PGHS-2 by exploiting a previously unrecognized binding s

73 this study, we report that the induction of PGHS-2 by IL-1beta is dramatically enhanced and prolonge

74 Attenuation of PGHS-2 by SLPI was accompanied by decreased production o

75 Prostaglandin endoperoxide H synthase 2 (PGHS-2) catalyzes the rate-limiting steps in the synthes

76 as prostaglandin endoperoxide H synthase-2 (PGHS-2), catalyzes the committed step in prostaglandin b

77 , binds only E(allo) in palmitic acid/murine PGHS-2 co-crystals.

78 in marrow cultures from mice lacking PGHS-2 (PGHS-2(-/-)) compared with wild-type (PGHS-2(+/+)) cultu

79 stances calculated and determined by EPR for PGHS-2 complexed with arachidonic acid, flurbiprofen, an

80 sis, and how differences in the structure of PGHS-2 confer on this isozyme differential sensitivity t

81 induces a conformational change in the holo-PGHS-2, converting it to a structure similar to those ob

82 NS-398, a highly selective inhibitor of PGHS-2 could inhibit substantial basal prostaglandin E2

83 Two forms of PGHS exist, PGHS-1 (COX-1) and PGHS-2 (COX-2).

84 Thus, KAT-50 cells express the inefficient PGHS-2/cPGES pair, and this results in modest PGE(2) pro

85 GHS-2 (PGHS-2(-/-)) compared with wild-type (PGHS-2(+/+)) cultures.

86 roid hormone (PTH), was reduced by 60-70% in PGHS-2(-/-) cultures relative to wild-type cultures, an

87 The hydroperoxide initiator requirement for PGHS-2 cyclooxygenase is about 10-fold lower than for PG

88 S-1 cyclooxygenase cooperativity and changed PGHS-2 cyclooxygenase kinetics from saturable to coopera

89 considerably higher than that of the control PGHS-2 cyclooxygenase.

90 he expression of prostaglandin H synthase-2 (PGHS-2, cyclooxygenase) message and protein in alveolar

91 pathway in vivo, we engineered a del595-612 PGHS-2 (Delta 18 COX-2) knock-in mouse lacking this 18-a

92 PGHS-2-dependent delayed-phase PGD2 generation elicited

93 peroxynitrite (OONO(-)) generator inhibited, PGHS-2-dependent prostaglandin production.

94 n of PGHS-2, or deletion of the receptor for PGHS-2-derived PGI(2), was shown to accelerate thromboge

95 and their adverse effects by suppression of PGHS-2-derived prostacyclin (PGI(2)) and PGE(2).

96 lates one-half of the subunits of the native PGHS-2 dimer, the Ecat subunits.

97 acids (FAs) are bound at both COX sites of a PGHS-2 dimer.

98 We examined this concept using human PGHS-2 dimers composed of combinations of Y385F, R120Q,

99 (0.0001%), darbufelone appears inactive with PGHS-2 due to a detergent interaction that is detectable

100 PGHS-2 efficiently oxygenated 3-HPAA to prostaglandin an

101 s indicate that the ultimate effect of NO on PGHS-2 enzyme activity and expression is dictated by the

102 purified ovine PGHS-1 and murine recombinant PGHS-2 equally.

103 HS-2 is only modestly inhibited by EPA (i.e. PGHS-2 exhibits a marked preference for AA when EPA and

104 These results imply that native PGHS-2 exhibits half-of-sites reactivity.

105 e concentration, whereas the second isoform, PGHS-2, exhibits saturable kinetics.

106 His388Tyr PGHS-2, expressed in insect cells and purified to homoge

107 ther explore the possible connection between PGHS-2 expression and beta-catenin/LEF-1 DNA complex for

108 All donors lost their ability to modulate PGHS-2 expression and function when decayed.

109 , NOR-1 and SNAP, and found that they caused PGHS-2 expression and PGE2 production.

110 e growth factor/EGF receptor loop regulating PGHS-2 expression and PGE2 synthesis in bronchial epithe

111 PGHS-2 expression in dermal fibroblasts is also increase

112 Taxol and taxotere each induced PGHS-2 expression in human monocytes suspended in 10% hu

113 zing antibodies could attenuate constitutive PGHS-2 expression in KAT-50 cells, suggesting that endog

114 between oestradiol and BCO in the control of PGHS-2 expression in the fetal brainstem.

115 Thus, unprovoked PGHS-2 expression might be considerably more widespread

116 mally expressed, in primary astrocytes where PGHS-2 expression was induced by lipopolysaccharide (LPS

117 Furthermore, increased PGHS-2 expression was observed in intestinal epithelial

118 In contrast to its effects on PGHS-2 expression, leukoregulin fails to alter PGHS-1 le

119 of the physiologic importance of epithelial PGHS-2 expression, supernatants from bacteria-infected i

120 t endogenous IL-1alpha synthesis was driving PGHS-2 expression.

121 cetate, and serum transiently down-regulated PGHS-2 expression.

122 ndoperoxide H synthases-1 and -2 (PGHS-1 and PGHS-2), four short amphipathic helices near the amino t

123 are reportedly formed via aspirin-acetylated PGHS-2 from eicosapentaenoic acid and docosahexaenoic ac

124 a number of studies suggest that PGHS-1 and PGHS-2 function independently to form prostanoids that s

125 We find that human PGHS-2 functions as a conformational heterodimer having

126 the free FA pool in the environment in which PGHS-2 functions in cells, the FA tone, is a key factor

127 To investigate the mechanism of the PGHS-2 gene expression in response to cerebral hypoperfu

128 These results indicate that PGHS-2 gene expression is induced by oxygen and glucose

129 nases are upstream mediators of ET-1-induced PGHS-2 gene expression through activation of non-recepto

130 and the complex mechanisms for regulation of PGHS-2 gene expression.

131 Native and ASA-treated PGHS-2 had lipoxygenase K(m) values considerably higher

132 erodimers in which a native subunit of human PGHS-2 has been coupled to a subunit having a defect wit

133 A V349A substitution in PGHS-2 has similar, minor effects on the rates of oxygen

134 of prostaglandin endoperoxide H synthase-2 (PGHS-2) has been implicated in pathological conditions s

135 ping functions, and the "inducible" isoform, PGHS-2, has been implicated in cellular responses to cyt

136 nit and a native subunit (i.e. Mutant/Native PGHS-2) have COX activities similar to native PGHS-2.

137 With some heterodimers (e.g. Y385F/Native PGHS-2), heme binds with significantly higher affinity t

138 With other heterodimers (e.g. S530A/Native PGHS-2), heme binds with similar affinities to both subu

139 and COX sites of monomers was detected in a PGHS-2 heterodimer comprised of a Q203R monomer having a

140 dicate that the structure of the solubilized PGHS-2 holoenzyme measured in solution differs from the

141 lution differs from the crystal structure of PGHS-2 holoenzyme obtained by x-ray analysis.

142 e inter-residue distances determined for the PGHS-2 holoenzyme using EPR were 1-7.9 A shorter than th

143 r than those of the crystal structure of the PGHS-2 holoenzyme.

144 ablished that only one monomer of the native PGHS-2 homodimer binds flurbiprofen tightly.

145 For PGHS-2, however, the transition between Intermediates I

146 In contrast, we report here that R120Q human PGHS-2 (hPGHS-2) and native hPGHS-2 have very similar ki

147 GHS-1 (oPGHS-1) and residues 59-108 in human PGHS-2 (hPGHS-2).

148 present study with the "inducible" isoform (PGHS-2), hydroperoxide was also found to generate a radi

149 ith inhibitor, darbufelone potently inhibits PGHS-2 (IC(50) = 0.19 microM) but is much less potent wi

150 Anaerobic addition of AA to ASA-PGHS-2 immediately after formation of the wide singlet r

151 Anaerobic addition of AA to PGHS-2 immediately after formation of this radical led t

152 ly as taxol, did not alter the expression of PGHS-2, implying that its induction in RAW 264.7 murine

153 Taxol induced PGHS-2 in human and murine monocytes via a p38 mitogen-a

154 helium expresses high constitutive levels of PGHS-2 in situ and in vitro and this enzyme is active in

155 that oestradiol increases the expression of PGHS-2 in specific fetal brain regions, and that there i

156 on of prostaglandin endoperoxide synthase-2 (PGHS-2) in ovine fetal brain regions.

157 he modulation of prostaglandin H synthase-2 (PGHS-2) in primary mouse cortical astrocytes and COS-7 c

158 ndin H synthase-1 and synthase-2 (PGHS-1 and PGHS-2) in the normal lung and in allergic lung response

159 1 s-1 for PGHS-1 and 2.5 x 10(7) M-1 s-1 for PGHS-2, indicating that the isoforms have similar initia

160 acting in an autocrine fashion, to regulate PGHS-2 induction and IL-6 secretion in mouse BMMC.

161 arily dampens and limits the duration of the PGHS-2 induction by IL-1beta.

162 However, there was no impairment of PGHS-2 induction in BMMC deficient in hematopoietic PGD

163 PGHS-2 induction, but not IL-6 secretion, was impaired i

164 ma, elicited a 2- to 3-fold amplification of PGHS-2 induction, delayed-phase PGD(2) generation, and I

165 Compounds usually associated with PGHS-2 induction, including interleukin-1beta (IL-1beta)

166 and interrupting this pathway attenuates the PGHS-2 induction.

167 Addition of nimesulide to ASA-treated PGHS-2 inhibited the lipoxygenase and resulted in a narr

168 or PGHS-1 in the presence or absence of the PGHS-2 inhibitor, NS-398.

169 ibitor and an R0 of 21 A for PGHS-2 with the PGHS-2 inhibitor.

170 2 (COX-2), converts arachidonic acid to PGH2 PGHS-2 is a conformational heterodimer composed of allos

171 PGHS-2 is a sequence homodimer.

172 PGHS-2 is also induced by CD40 engagement in a time-depe

173 y expressed in most healthy tissues, whereas PGHS-2 is highly inducible and currently thought to be e

174 itutive and inducible forms of PGHS and that PGHS-2 is induced by mitogens in this cell type.

175 and also indicate that the AA radical in ASA-PGHS-2 is more constrained than the corresponding radica

176 These data suggest that PGHS-2 is not necessary for wild-type bone development b

177 ising observation was that AA oxygenation by PGHS-2 is only modestly inhibited by EPA (i.e. PGHS-2 ex

178 nt near the amino terminus of the PGHS-1 and PGHS-2 isozymes act as membrane anchors.

179 r amino-terminal sequences of the PGHS-1 and PGHS-2 joined to the green fluorescent protein from Aequ

180 darbufelone is a noncompetitive inhibitor of PGHS-2 (K(i) = 10 +/- 5 microM).

181 selective for prostaglandin G/H synthase-2 (PGHS-2) (known colloquially as COX-2) were designed to m

182 inhibitors of prostaglandin G/H synthase-2 (PGHS-2; known colloquially as COX-2) increase the incide

183 The induction of PGHS-2 leads to a dramatically enhanced prostaglandin E2

184 cardiovascular consequences associated with PGHS-2-mediated PGI(2) suppression.

185 ter prednisone administration, whereas in CS PGHS-2 message and protein remained undetectable or, if

186 Both allergic PGHS-1(-/-) and PGHS-2(-/-) mice exhibited decreased baseline respirator

187 ological examination of bone from 5-week-old PGHS-2(-/-) mice revealed no abnormalities.

188 ly greater in PGHS-1(-/-) mice compared with PGHS-2(-/-) mice, and both were far greater than in wild

189 ia caused hypercalcemia in wild-type but not PGHS-2(-/-) mice.

190 ess in wild-type mice and in PGHS-1(-/-) and PGHS-2(-/-) mice.

191 development of airway hyperresponsiveness in PGHS-2(-/-) mice.

192 m PGHS-1(-/-) mice, relative to wild-type or PGHS-2(-/-) mice.

193 An S121P substitution in both PGHS-2 monomers yields a variant (S121P/S121P PGHS-2) th

194 Whereas OGD stimulated robust increases in PGHS-2 mRNA abundance, neither oxygen nor glucose depriv

195 well as ionomycin and thapsigargin-mediated PGHS-2 mRNA and protein formation.

196 ionomycin-, thapsigargin-, and IL-1-mediated PGHS-2 mRNA and protein induction.

197 calcium ATPase, mimicked the ET-1-stimulated PGHS-2 mRNA and protein induction.

198 Our data demonstrated that induction of both PGHS-2 mRNA and protein reached peak levels ( approximat

199 In AS, PGHS-2 mRNA and protein significantly increased after pr

200 50 cells express high levels of constitutive PGHS-2 mRNA and protein under basal culture conditions.

201 Surprisingly, PGHS-2 mRNA and protein were easily detected in normal t

202 lls expressed significantly higher levels of PGHS-2 mRNA and protein, and generated more PGE2.

203 Steady-state levels of PGHS-2 mRNA are increased within 1.5 h of leukoregulin a

204 ET-1-, ionomycin-, and thapsigargin-induced PGHS-2 mRNA expression and protein formation was inhibit

205 s did not inhibit interleukin (IL)-1-induced PGHS-2 mRNA expression and protein synthesis.

206 E2 formation, PGHS-2 protein expression, and PGHS-2 mRNA expression in RAW 264.7 murine macrophages.

207 At baseline, the amounts of PGHS-2 mRNA in AM and BM varied within a similar range a

208 adiol, by itself, increased the abundance of PGHS-2 mRNA in brainstem and cerebellum, and augmented t

209 brainstem and cerebellum, and augmented the PGHS-2 mRNA response to BCO in brainstem.

210 sed in fetal brainstem and hypothalamus, and PGHS-2 mRNA was increased in fetal brainstem.

211 xhibited the expected decrease in stimulated PGHS-2 mRNA with glucocorticoids.

212 ed radical (a 21G narrow singlet) in a Y371F PGHS-2 mutant lacking cyclooxygenase activity failed to

213 However, Q203V PGHS-1 and PGHS-2 mutants catalyzed heterolytic cleavage of peroxid

214 mechanism of hydroperoxide reduction by the PGHS-2 mutants was investigated using 15-hydroperoxyeico

215 In contrast, aspirin-treated PGHS-2 (ASA-PGHS-2) no longer forms prostaglandins but retains oxyge

216 he pentadienyl AA radical obtained in native PGHS-2 or a 26-28-G singlet radical.

217 did not result from covalent modification of PGHS-2 or damage to the heme moiety.

218 lective inhibition, knockout, or mutation of PGHS-2, or deletion of the receptor for PGHS-2-derived P

219 ough the preferential peroxide activation of PGHS-2 over PGHS-1 seen in mammals was conserved in the

220 is study suggests that NO may be involved in PGHS-2 overexpression in conditionally immortalized mous

221 To ascertain the effect of NO on PGHS-2 overexpression, we tested NO-releasing compounds,

222 Retention of PGHS-2 oxygenase activity was thus associated with reten

223 versus 3-series compounds were observed with PGHS-2, PGD synthases, microsomal PGE synthase-1 and EP1

224 reduced in marrow cultures from mice lacking PGHS-2 (PGHS-2(-/-)) compared with wild-type (PGHS-2(+/+

225 substrates for the peroxidase activities of PGHS-2, PGHS-1, and glutathione peroxidase (GPx).

226 ortions and stability of the two radicals in PGHS-2 pretreated with peroxide.

227 Both native and ASA-treated PGHS-2 produced only the R stereoisomer of 11- and 15-HE

228 (2) in the normal mouse lung; (b) PGHS-1 and PGHS-2 products limit allergic lung inflammation and IgE

229 Human PGHS-2 promoter constructs (-1840/+123 and -831/+123) fu

230 in exposure caused a modest increase in lung PGHS-2 protein and a corresponding increase in BAL fluid

231 xol plus IFN-gamma increased PGE2 formation, PGHS-2 protein expression, and PGHS-2 mRNA expression in

232 sion of PGHS-2 RNA and increased recovery of PGHS-2 protein in NHBECs.

233 PGHS-1 and PGHS-2 protein levels did not reflect the changes in the

234 NO(*) synergistically enhanced LPS-mediated PGHS-2 protein synthesis.

235 tex in response to BCO, and the abundance of PGHS-2 protein was increased by both oestradiol and BCO

236 PGHS-2 protein was present in AM and BM from most AS, bu

237 ked the induction of mRNA, the expression of PGHS-2 protein, and the formation of PGE2.

238 We expressed recombinant PGHS-2 proteins containing single Tyr --> Phe mutations

239 The ability of the PGHS-2 proteins to catalyze two-electron hydroperoxide r

240 We now have found the ASA-treated PGHS-2 radical to be indistinguishable from that in cont

241 , nimesulide, similarly resulted in a narrow PGHS-2 radical.

242 For nimesulide-treated PGHS-2, radical formed in concert with Intermediate II,

243 thacin-treated PGHS-1 and nimesulide-treated PGHS-2 rapidly formed narrow singlet EPR (25-26 G in PGH

244 or amino acids 1-139 and 1-136 of PGHS-1 and PGHS-2, respectively, which include the signal peptides,

245 GHS-2 as indicated by enhanced expression of PGHS-2 RNA and increased recovery of PGHS-2 protein in N

246 Induction of PGHS-2 RNA in IFN-gamma-treated NHBECs, which peaked at

247 te the release of PGE2 and the expression of PGHS-2 RNA in NHBECs.

248 ostaglandin release and/or the expression of PGHS-2 RNA in these cell lines was upregulated by other

249 , a prostaglandin endoperoxide H synthase-2 (PGHS-2)-selective inhibitor.

250 SC58125, a PGHS-2-selective inhibitor, could attenuate the inductio

251 In PGHS-2, some wide doublet (30 G) was present at early ti

252 In addition, PGHS-2-specific fluorescence was concentrated often as a

253 PGHS-2-specific inhibitors including NS398, DuP-697, and

254 Attenuating Jak2 increases PGHS-2 steady-state mRNA levels, a consequence of increa

255 s, and they required lower GdmHCl levels for PGHS-2 than for PGHS-1.

256 ssion by cytosolic glutathione peroxidase in PGHS-2 than in PGHS-1.

257 h less important for arachidonate binding to PGHS-2 than to PGHS-1.

258 ore significantly to arachidonate binding to PGHS-2 than to PGHS-1.

259 nation are typically 1.5-2 times higher with PGHS-2 than with PGHS-1.

260 d that osteoclast formation was 50% lower in PGHS-2(-/-) than in wild-type cultures, apparently becau

261 GHS-2 monomers yields a variant (S121P/S121P PGHS-2) that has 1.7-1.8 times the Vmax of native PGHS-2

262 is inducible and works more efficiently with PGHS-2, the inflammatory cyclooxygenase, while the cytop

263 In PGHS-2, this transition results from radical migration f

264 e chain structures of Asn-382 and Thr-383 in PGHS-2 thus selectively influence two important aspects

265 te the independent functioning of PGHS-1 and PGHS-2 to differences in their subcellular locations.

266 te-directed mutagenesis of recombinant human PGHS-2 to focus on one heme-vicinity residue that diverg

267 ons with the wide singlet tyrosyl radical of PGHS-2 to generate a radical intermediate that was analy

268 c regulation likely underlies the ability of PGHS-2 to operate at low AA concentrations, when PGHS-1

269 ed in a narrow radical EPR like that seen in PGHS-2 treated with TNM or nimesulide alone.

270 o PGHS-1, only the formation kinetics of the PGHS-2 tyrosyl radical matched the Intermediate II absor

271 ogether, these results suggest that the same PGHS-2 tyrosyl radical serves as the oxidant for both cy

272 two steps are reversible for both isoforms; PGHS-2 undergoes the first and last steps more readily t

273 f the active sites of ovine PGHS-1 and human PGHS-2 using denaturation with guanidinium hydrochloride

274 This is unlike the corresponding native PGHS-2 variant and suggests that S121P substitutions als

275 Additionally, the S121P/S121P PGHS-2 variants in which Pro-127 and Ser-541 are replace

276 Complete inactivation of PGHS-2 was achieved with 10 muM 3-HPAA.

277 PGHS-2 was also found in lesions, but 3-nitrotyrosine in

278 es and COS-7 cells engineered to overexpress PGHS-2 was assessed.

279 Suppression of PGHS-2 was detected with 0.1 microg/ml of SLPI with a su

280 iption was eliminated in the COS-7 system as PGHS-2 was maximally expressed, in primary astrocytes wh

281 ons tested, indicating that the k2 value for PGHS-2 was much greater than that for PGHS-1.

282 PGHS-2 was selectively, dose-dependently, and irreversib

283 Induction of both mPGES and PGHS-2 was susceptible to either chemical inhibition or

284 e can also induce a conformational change in PGHS-2 was unexpected, and the magnitude of changes sugg

285 roduced into the membrane-binding helices of PGHS-2 was used to calculate the inter-helical distances

286 ypothesized that prostaglandin H synthase-2 (PGHS-2) was one of the unidentified genes induced by tax

287 ase activity of the inducible isozyme, i.e., PGHS-2, was also inhibited by these compounds.

288 onal role of the wide singlet radical in ASA-PGHS-2, we have examined the ability of this radical to

289 to TPA is due to the continuous induction of PGHS-2, which is dependent upon PLD activation.

290 Reaction of PGHS-2 with a tyrosine-modifying reagent, tetranitrometh

291 Treatment of PGHS-2 with aspirin (acetyl salicylic acid, ASA) was pre

292 ormation of a narrow singlet in complexes of PGHS-2 with cyclooxygenase inhibitors.

293 Inhibition of PGHS-2 with darbufelone is time dependent: with no prein

294 29-31 gauss (G) was generated by reaction of PGHS-2 with ethyl hydroperoxide.

295 one-quarter of the monomers of S530A/Native PGHS-2 with or without heme.

296 h the PGHS-1 inhibitor and an R0 of 21 A for PGHS-2 with the PGHS-2 inhibitor.

297 ts of prostaglandin-endoperoxide synthase-2 (PGHS-2) with changes in the peroxidase active site were

298 roduction of 2-series prostanoids from AA by PGHS-2 would be expected to decrease in proportion to th

299 ce of protein; only Q189N retained wild-type PGHS-2 (wtPGHS-2) activity.

300 e radical to Tyr385 in the recombinant human PGHS-2 Y504F mutant was exploited in examining the effec