ライフサイエンスコーパス: Lefty

1 diffusion rates of Nodal and its antagonist Lefty.

2 astula stage embryo, a process that requires lefty.

3 signaling, we validated the Nodal inhibitor Lefty.

4 ellular Nodal antagonists Cerberus-Short and Lefty.

5 the signaling gene nodal and its antagonist lefty.

6 ist squint and the TGF-beta Nodal antagonist lefty.

7 cular mechanisms underlying this function of Lefty.

8 ited, and include follistatin, Cerberus, and Lefty.

9 FN is also required for the expression of Lefty 1/2 and activation of SMADs 2 and 3 at the floor p

10 bryos, even in the absence of normal antivin/lefty-1 and Pitx2 expression, strongly suggests that hea

11 etry in lateral plate mesoderm (LPM) antivin/lefty-1 and Pitx2 expression.

12 demonstrate that retinoic acid (RA) controls Lefty-1 expression in a pathway downstream or parallel t

13 Expression of the left-specific gene Lefty-1 is absent in Shh(-/-) embryos, suggesting that t

14 In the absence of Smad5, lefty-1 was expressed at very low or undetectable levels

15 /- embryos, the expression of Ebaf (formerly lefty-1) in the left side of the floor plate and Leftb (

16 tivin receptor IIa, sonic hedgehog, Caronte, Lefty-1, and Fgf8 to be unaffected by the lack of retino

17 beta family signaling proteins (i.e., nodal, lefty-1, lefty-2, activin receptor type IIB, and Smad2)

18 rming growth factor-beta superfamily members Lefty-1, Lefty-2, and nodal comprise a regulatory pathwa

19 cient embryos, we examined the expression of lefty-1, lefty-2, nodal, and Pitx2 since the asymmetric

20 These data suggest that Smad5 is upstream of lefty-1, nodal, and lefty-2, and as a consequence also o

21 lecular interactions between Activin, FGF-8, Lefty-1, Nodal, BMPs and Car that cooperate to control l

22 y defects could be the result of the lack of Lefty-1.

23 h and RA pathways converge in the control of Lefty-1.

24 omized, and at earlier stages in development lefty-2 and nodal, which are normally expressed asymmetr

25 asymmetric patterns of expression of nodal, lefty-2 and Pitx2.

26 ally that left-sided expression of pitx2 and lefty-2 are also perturbed in Furin-deficient embryos.

27 side of the floor plate and Leftb (formerly lefty-2), nodal and Pitx2 in the left lateral plate meso

28 ly signaling proteins (i.e., nodal, lefty-1, lefty-2, activin receptor type IIB, and Smad2) in L-R ax

29 hat Smad5 is upstream of lefty-1, nodal, and lefty-2, and as a consequence also of Pitx2, and Smad5 i

30 wth factor-beta superfamily members Lefty-1, Lefty-2, and nodal comprise a regulatory pathway whose f

31 ery low or undetectable levels, while nodal, lefty-2, and Pitx2 were expressed bilaterally.

32 ryos, we examined the expression of lefty-1, lefty-2, nodal, and Pitx2 since the asymmetric expressio

33 The deduced amino acid sequences of LEFTY A and LEFTY B are more similar to each other than

34 rt characterization of two Lefty homologues, LEFTY A and LEFTY B, separated by approximately 50 kb on

35 LEFTY A is identical to ebaf, a cDNA previously identifi

36 e in the cysteine-knot region of the protein LEFTY A, and the phenotype of affected individuals is ve

37 mental pathways including those of TGF-beta (Lefty A, NMA, follistatin), homeo domain (HoxD1, Meis2,

38 ed one nonsense and one missense mutation in LEFTY A.

39 Here, we report on the effect of lefty, a novel member of the TGF-beta family, on the hom

40 show that TGF-beta signaling is inhibited by lefty, a novel member of the TGF-beta superfamily.

41 nodal and the inhibitors of Nodal signaling, lefty-A and lefty-B, are down-regulated very early upon

42 tivation of Smad2/3 and expression of nodal, lefty-A and lefty-B, while inhibition of ALK4/5/7 by the

43 K3-inhibitor, BIO, high expression of nodal, lefty-A, and lefty-B also requires activation of ALK4/5/

44 that ECM is a principal surface of Nodal and Lefty accumulation.

45 gesting cleavage to be an essential step for lefty activation.

46 ured the biophysical properties of the Nodal/Lefty activator/inhibitor system during zebrafish embryo

47 In particular, using a novel assay for Lefty activity in mammalian cell culture, we find that L

48 nge Nodal signal Cyclops is not regulated by Lefty activity.

49 cells do not express the inhibitor to Nodal, Lefty, allowing them to overexpress this embryonic morph

50 these signals, including the Nodal inhibitor Lefty, an atypical TGFbeta factor, are induced by Nodal.

51 by EGF-CFC cofactors and antagonists of the Lefty and Cerberus families of proteins, allowing precis

52 Xnr1/Nodal, together with inhibitors such as Lefty and Coco/Cerl2, have been shown to provide the sig

53 sion analysis demonstrates that a balance of lefty and cyclops signaling is required for normal mesen

54 teractions among co-expressed members of the lefty and nodal subfamilies of TGF-beta signaling molecu

55 ality of the viscera (cyclops/nodal, antivin/lefty and pitx2) are coexpressed on the left side of the

56 ings provide a new insight on the actions of lefty and suggest that this cytokine plays an active rol

57 n of the endogenous Nodal inhibitors Lefty2 (Lefty) and truncated Cerberus (Cerb-S) and by pharmacolo

58 on TGFbeta-related signals, including Nodal, Lefty, and BMPs.

59 C co-receptor Cripto and can be inhibited by Lefty antagonists.

60 The secreted TGFbeta factor Lefty antagonizes Nodal signaling during vertebrate embr

61 f discordant monozygotic twins suggests that lefties are one gene apart from righties.

62 llularly, the Nodal antagonists Cerberus and Lefty are permissive for ADMP activity.

63 asymmetric expression patterns of nodal and lefty are randomized in iv/iv embryos, suggesting that i

64 n contrast to earlier reports that nodal and lefty are upstream of pitx2, ectopic pitx2c in other reg

65 deduced amino acid sequences of LEFTY A and LEFTY B are more similar to each other than to Lefty1 or

66 ization of two Lefty homologues, LEFTY A and LEFTY B, separated by approximately 50 kb on chromosome

67 BIO, high expression of nodal, lefty-A, and lefty-B also requires activation of ALK4/5/7.

68 e inhibitors of Nodal signaling, lefty-A and lefty-B, are down-regulated very early upon differentiat

69 Smad2/3 and expression of nodal, lefty-A and lefty-B, while inhibition of ALK4/5/7 by the kinase inhi

70 h a striking conservation of the inhibitors, Lefties, but differential targeting of the activators, N

71 Fibroblastic cells forced to express lefty by retroviral transduction lost their ability to d

72 eceptor, Acvr2b, and to the Nodal inhibitor, Lefty, by fluorescence cross-correlation spectroscopy.

73 Furthermore, Lefty can also interact with EGF-CFC proteins and preven

74 First, Lefty can block Nodal signaling at a distance.

75 vity in mammalian cell culture, we find that Lefty can inhibit signaling by Nodal but not by Activin

76 We show that Lefty can interact with Nodal in solution and thereby bl

77 PC cleavage in the lefty protein allowed the lefty cleavage sites to be identified.

78 This suggests that Lefty-dependent modulation of organizer signaling might

79 Lefty did not induce Smad2 or Smad5 phosphorylation, Sma

80 The action of lefty does not appear to depend on protein synthesis, in

81 ypoblast, and finally a late inhibition from Lefty emitted by the primitive streak itself.

82 is directly associated with the secretion of Lefty, exclusive to hESCs, because it is not detected in

83 Differentiating EBs derived from Lefty expressing hESCs generated a dense network of beta

84 beta-tubulin III positive neurites, and when Lefty expressing hESCs were grown as a monolayer and all

85 ants can be rescued by ectopic expression of lefty far from its normal expression domain or by spatia

86 ssing of the lefty polypeptide to the 28-kDa lefty form.

87 and biochemical analysis showed transfer of Lefty from left LPM to right LPM, providing direct evide

88 Moreover, reduction in Lefty gene expression is linked to elevated DNA methylat

89 In mouse, lefty genes play critical roles in the left-right (L-R)

90 Analysis of Nodal and Lefty gradients revealed that Nodals have a shorter rang

91 s fluorescence recovery assays revealed that Leftys have a higher effective diffusion coefficient tha

92 -labeling analysis indicated that Nodals and Leftys have similar clearance kinetics, whereas fluoresc

93 We now report characterization of two Lefty homologues, LEFTY A and LEFTY B, separated by appr

94 nism by Car induces asymmetric expression of Lefty in the midline, preventing spread of left-sided si

95 Similarly, lefty inhibited both BMP-mediated Smad5 phosphorylation

96 Moreover, lefty inhibited the events that lie downstream from R-Sm

97 e diffusion coefficient of Nodal ligands and Lefty inhibitors in live zebrafish embryos by fluorescen

98 Nodal (here, Xnr1 or Nodal1 in Xenopus) and Lefty interact in a cross-regulatory relationship in mes

99 iding direct evidence that left-side-derived Lefty is a significant influence in ensuring the continu

100 derm inducer Nodal to activate its inhibitor Lefty is required for development.

101 cells to a hESC microenvironment (containing Lefty) leads to a dramatic down-regulation in their Noda

102 in LPM, and corresponding loss of downstream Lefty (lft1 and lft) expression, and aberrant brain and

103 e developmental signalling factors Nodal and Lefty may provide a real example of the kind of reaction

104 ct is not localized, and hence refractory to Lefty-mediated enforcement of localization.

105 We detected Lefty moving faster than Nodal, with evidence that intac

106 Protection of squint or lefty mRNAs from miR-430 resulted in enhanced or reduced

107 thout feedback: Lethal patterning defects in lefty mutants can be rescued by ectopic expression of le

108 We find that zebrafish lefty mutants exhibit excess Nodal signaling and increas

109 We hypothesized that Lefty mutations may be associated with human LR-axis mal

110 linked to elevated DNA methylation, as both Lefty-Nodal signalling and normal morphogenesis are larg

111 ated oxidation of 5-methylcytosine modulates Lefty-Nodal signalling by promoting demethylation in opp

112 data also provide insights into the way that lefty/nodal signals interact in the initiation of differ

113 Simultaneous protection of squint and lefty or absence of miR-430 caused an imbalance and redu

114 EBs derived from either Lefty or Cerb-S expressing hESCs also contained a greate

115 s, embryoid bodies (EBs) derived from either Lefty or Cerb-S overexpressing hESCs showed increased ex

116 tments reproduced the neuralising effects of Lefty overexpression in hESCs.

117 Lefty perturbed TGF-beta signaling by inhibiting the pho

118 a, which eventually induces asymmetric Nodal/Lefty/Pitx2 expression on the left side of the lateral p

119 PCs showed activity in the processing of the lefty polypeptide to the 28-kDa lefty form.

120 Lefty polypeptides, novel members of the transforming gr

121 inducing MAPK activity, indicating that the lefty precursor is biologically active.

122 prevented the proteolytic processing of the lefty precursor to the 34- and 28-kDa forms, respectivel

123 tion analysis showed that PC5A processed the lefty precursor to the 34-kDa form in vivo, whereas furi

124 bryonic laterality, we studied their role in lefty processing.

125 By expressing Xnr1 and Lefty proproteins that produce mature functional epitope

126 e consensus sequences for PC cleavage in the lefty protein allowed the lefty cleavage sites to be ide

127 Surprisingly, the 42-kDa lefty protein was also capable of inducing MAPK activity

128 It is currently thought that Lefty proteins act as feedback inhibitors of Nodal signa

129 te mesendoderm induction in vertebrates, and Lefty proteins antagonize it.

130 Nodal and Lefty proteins belong to divergent subfamilies of the TG

131 esults provide mechanistic insights into how Lefty proteins can achieve efficient and stringent regul

132 s in zebrafish and frogs have suggested that Lefty proteins can act as long-range inhibitors for Noda

133 distinct and unexpected mechanisms by which Lefty proteins can antagonize Nodal activity.

134 We present three lines of evidence that Lefty proteins diminish the range of Squint signaling by

135 These results indicate that Lefty proteins restrict the activity range of Nodal sign

136 vealed that Nodals have a shorter range than Lefty proteins.

137 which Squint induces mesoderm is reduced by Lefty proteins.

138 Thus, lefty provides a repressed state of TGF-beta- or BMP-res

139 ajor determinant of the differences in Nodal/Lefty range and provide biophysical support for reaction

140 Second, Lefty regulates the range of Squint signaling before reg

141 Here, we characterize the Xenopus lefty-related factor antivin (Xatv).

142 Lefty repressed TGF-beta-induced expression of reporter

143 Third, Lefty restricts the range of Squint activity in squint m

144 We also find that Lefty restricts the response to both high and low levels

145 Transfection of different cell lines with lefty resulted in expression of a 42-kDa protein, which

146 on of Smad2/3 binding at the Nodal inhibitor lefty, resulting in direct repression of lefty that is c

147 patterning is directed by a conserved nodal/lefty signaling cascade on the left side of the embryo,

148 lly left-sided expression of the Nodal-Pitx2/Lefty signaling system are also present in the cavefish

149 rning are controlled upstream of Nodal-Pitx2/Lefty signaling.

150 processing as a mechanism for regulation of lefty signaling.

151 ing vertebrate embryogenesis, members of the Lefty subclass of Transforming Growth Factor-beta (TGFbe

152 The Lefty subfamily of TGFbeta signaling molecules has been

153 tor lefty, resulting in direct repression of lefty that is critical for mesendoderm specification.

154 In addition, lefty transduction significantly decreased collagen type

155 efty, which arises mainly from repression of Lefty translation by the microRNA miR-430.

156 tive form of lefty, we studied the effect of lefty treatment on pluripotent P19 cells.

157 Nodal and lefty, two genes that are normally expressed only in the

158 other components of this cascade (Nodal and Lefty) was unchanged after blocking N-cadherin function,

159 To identify the biologically active form of lefty, we studied the effect of lefty treatment on pluri

160 differentially timed production of Nodal and Lefty, which arises mainly from repression of Lefty tran

161 Lefty, which is normally also expressed in the floorplat

162 We further show that the Nodal inhibitor Lefty, while biochemically capable of long-range diffusi

163 enes (Xnrs) by extracellular Xenopus antivin/lefty (Xatv/Xlefty)-mediated functional antagonism and B

164 We propose that the induction of lefty/Xatv in the left LPM by nodal/Xnr1 provides an eff

165 Here, Xenopus Lefty (Xlefty) function was blocked by injection of anti

166 Here, we show that Xenopus lefty (Xlefty) is expressed both bilaterally in symmetri