PTEN impedes EMT during chick embryo gastrulation

PTEN has been considered as one of the important anti-oncogenes,which possesses very wide biological ac-tivities.Endogenous PTEN genes begin to express in epiblast during chick embryo gastrulation,and then the expression extends to neural plate and mesoderm.This suggests that PTEN might be involved in cell migration,proliferation,and dif-ferentiation during early embryo development.In this study,we employed in vivo approach to explore if endogenous PTEN participates in EMT(Epithelial-mesenchymal transition) in early chick embryo.PTEN was initially detected to highly ex-press in primitive streak during chick gastrulation,in which EMT occurs,and subsequently mesoderm structure such as somites etc.Then,overexpression of both Wt PTEN-GFP and Wt PTEN-GFP positive transplantation of primitive streak resulted in cell accumulation in primitive streak in the development hereafter,indicating that EMT was blocked in both of our assays,either whole embryo transfection of Wt PTEN-GFP or transplantation of Wt PTEN-GFP primary streak tissue.Finally down-regulation of PTEN gene in one side using PTEN siRNA led to reduce the more number of mesoderm cells inPTNE siRNA side than normal side,which suggests that PTEN gene is probably involved in regulating EMT process in development of early embryonic gastrulation.