胚胎干细胞(续).pdf

《胚胎干细胞(续).pdf》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、第七课胚胎干细胞的自我更新和亚全能性的分子基础(续）LIF-gp130-SHP-2-ERK信号LIF处理ES细胞时，还可以使Gp130的Y118位酪氨酸发生磷酸化，进而磷酸化酪氨酸激酶SHP-2(SH2-domaincontainingtyrosinephosphatase)。进而通过接头蛋白Grb2和Grb1活化ERK。Differentiation接头蛋白Growthfactorreceptor-boundprotein2（Grb2）是一种接头蛋白，在细胞信号转导和细胞通讯中起到关键作用。KOGrb2的胚胎中不能形成PrE结构。GRB2-assoc

2、iated-bindingprotein1（Gab-1），协助Grb2起到蛋白对接（docking）的作用。增加Gab1的表达可以促进Gp130介导的ERK的活化。SHP-2和ERK信号与ES细胞维持自我更新和亚全能性的影响SuppressionofSHP-2andERKSignallingPromotesSelf-RenewalofMouseEmbryonicStemCellsDevBiol.1999Jun1;210(1):30-43Gp130(Y118)-dependentphosphorylationofSHP-2inEScells构建了G-CSF

3、R胞外域+gp130胞内域(GR/gp130278)和G-CSFR+gp130胞内域（Y118位酪氨酸突变成苯丙氨酸Y118F）载体，稳定转染到ES细胞中。EScellsexpressingeithertheGRgp(278)ortheGRgp(Y118F)chimaericreceptorswereinducedwithIL-6(100ng/mlplussIL-6R)orG-CSF(30ng/ml)for15min.β-gal-Oct4reportconstructEffectofmutatingtyrosine118ongp130-dependents

4、elf-renewalandgrowthofEScellshyperactivationofsignalsdownstreamofgp130PhotomicrographsofrepresentativecoloniesformedbyGRgp(278)andGRgp(Y118F)transfectantsafter6daysculturewith300fg,30pg,and30ng/mlofG-CSF.AttenuationoftheSTAT3SignalIsMediatedviaTyrosine118EScells用IL-6/sIL-6R或者G-CSF

5、处理25分钟，然后换成没有细胞因子的培养基，Y118F细胞的磷酸化STAT3的量明显高于278的，而且保持时间更长。Tyrosine118IsNecessaryforActivationofERK1andERK2EffectoftheMEKinhibitor,PD098059,onEScellself-renewalandERKactivation.SHP-2突变对ES细胞分化为心肌细胞的影响Developmentofcardiomyocytesfromwild-typeandShp-2mutantEScells.Wild-type(+/+)andhomo

6、zygousShp-2mutant(-/-)EScellsweretrypsinizedandresuspendedinEScellmediumwithoutLIF.Oncogene.1998Jul30;17(4):433-9ExpressionofmusclecellmarkergenesWTSHP-2KODifferentiationoffibroblast-likeandepithelialcellsinLIFfreemedium(mediumreplacedeveryday).Wild-type(a,c)andmutant(b,d)Sensitiv

7、ityofEScellstoLIF.CellswerefirstseededintoEScellmediumsupplementedwithLIFat1000U/ml.Aftercellshadattachedtothedishes(12h),LIFconcentrationwasadjustedto60,15,4or0U/ml,andcellsweremaintainedinsuch`LIF-starving'mediumfor96h.LIF-gp130-SHP-2-ERK信号MutationChemicalinhibitorDifferentiatio

8、nSHP-2突变对胚胎发育的影响SHP-2的N端SH2结构的突变