Citation
- Authors: Yao, K., Ki, M. O., Chen, H., Cho, Y. Y., Kim, S. H., Yu, D. H., Lee, S. Y., Lee, K. Y., Bae, K., Peng, C., Lim, D. Y., Bode, A. M., Dong, Z.
- Year: 2014
- Journal: Stem Cell Res 12 139-52
- Applications: in vitro / DNA / jetPEI
- Cell type: HEK-293T
Description: Human embryonic kidney Fibroblast
Known as: HEK293T, 293T
Method
Virus production (retrovirus).
Abstract
Embryonic stem (ES) cells are pluripotent cells with the capacity for unlimited self-renewal or differentiation. Inhibition of MAPK pathways enhances mouse ES cell pluripotency characteristics. Compared to wildtype ES cells, jnk2(-/-) ES cells displayed a much higher growth rate. To determine whether JNKs are required for stem cell self-renewal or differentiation, we performed a phosphorylation kinase array assay to compare mouse ES cells under LIF+ or LIF- culture conditions. The data showed that activation of JNKs was induced by LIF withdrawal. We also found that JNK1 or 2 phosphorylated Klf4 at threonines 224 and 225. Activation of JNK signaling and phosphorylation of Klf4 inhibited Klf4 transcription and transactivation activity. Importantly, jnk1(-/-) and jnk2(-/-) murine embryonic fibroblasts (MEFs) exhibited a significantly greater potency in the ability to increase the number of iPS colonies compared with jnk wildtype MEFs. Overall, our results demonstrated that JNK1 and 2 play a negative role in reprogramming to pluripotent stem cells by suppressing Klf4 activity.