Bioinformatics. revealed that BCL2, as a downstream gene of the PI3K signal pathway, enhanced the expression of PI3K signal pathway receptors, such as FGFR2, and further promoted oxidoreductases activity and lipid metabolism, thus maintaining the survival and pluripotency of piPSCs. Conclusion Our data not only suggested that porcine BCL2 gene could enhance the survivability and chimeric ability of pPSCs, but also explained the positive feedback mechanism in this process, providing strong support for the chimeric experiment of pPSCs. Abstract Overexpression of porcine BCL2 gene promotes the expression of FGFR2 to resist cell death under conditions of stress. Furthermore, the survival rate and chimerism efficiency of porcine induce pluripotent stem cells were significantly improved. 1.?INTRODUCTION Pig is an important domestic animal, which not only provides a large amount of meat for human, but also can be used as an ideal medical model due to its close similarity to humans in organ anatomy, physiology and metabolism. 1 , 2 Pluripotent stem cells (PSCs) can maintain self\renewal and have the ability to differentiate into all cell types of biological individuals. 3 Therefore, the derivation of porcine PSCs has future utility in biomedical and porcine breeding. However, porcine PSCs, including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), still have great defects that lead it unavailable. 4 At present, each of the porcine embryonic stem cell\like cells (pESLCs) exhibited some features of pluripotency; however, these cells cannot Z-VAD-FMK maintain self\renewal for a long time. 5 , 6 , 7 Further investigation showed that only individual cell lines exhibited inefficient chimeras. 8 Porcine\induced pluripotent stem cells (piPSCs) can be obtained by ectopic expression of defined pluripotent factors and exhibited higher pluripotency compared with pESLCs. 9 Z-VAD-FMK , 10 , 11 Unfortunately, most of piPSCs also failed to contribute to chimeras with some exceptions that depended on genomic polymerase chain reaction (PCR) analysis. 12 , 13 Therefore, the biggest Rabbit Polyclonal to CNTN5 drawback to the present pPSCs is that it is still hard to contribute to efficient chimeras and was extremely sensitive to changes culture conditions, although they can be passaged for a long time and differentiate into three germ layers after injection into severe combined immunodeficiency (SCID) mice. 4 Culture conditions of pPSCs are more demanding, requiring growth factors and feeder, but even so it is prone to cell death and differentiation. 14 This may be one of the main reasons why the chimeric experiments of pPSCs continue to fail. This is a major problem that must be faced if the field is to move forward. Previous studies have shown that apoptosis is an initial barrier in the chimeric experiment. Inhibiting apoptosis can improve the survival ability to cope with stress conditions and the efficiency of embryo chimera formation, without affecting pluripotency of PSCs. 15 , 16 , 17 One strategy to enhance the survivability of stem cells is recombinant overexpression of anti\apoptotic genes or the addition of apoptotic inhibitors. 15 , 17 For example, Y\27632, a selective Rho\associated kinase (ROCK) inhibitor, has Z-VAD-FMK been shown to significantly diminish dissociation\induced apoptosis of stem cells. 18 The optimization of culture media for growth and survival can contribute to chimera formation in embryos. 19 B\cell lymphoma 2 gene (BCL2), one of the most particular interest is an anti\apoptotic gene, was first identified in human follicular lymphoma. 20 Many of the signals of improving survival converge at the BCL2 pathway. Previous studies showed that the expression of this gene can prevent apoptosis and reduces oxidative stress to improve the survival Z-VAD-FMK of human and mouse ESCs. 15 , 17 Further studies have shown that overexpression of BCL2 enables injected EpiSCs (epiblast stem cells) to survive.