The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Activation of AP-1 is required for bufalin-induced apoptosis in human leukemia U937 cells.

In a previous study, we demonstrated that bufalin caused apoptosis in human leukemia U937 cells by the anomalous activation of mitogen-activated protein kinase ( MAPK) via a signaling pathway that included Ras, Raf-1 and MAPK kinase-1. We report here the effect of bufalin on c-Jun N-terminal protein kinase (JNK), a member of the MAPK family, and on the signaling pathway downstream of MAPKs in U937 cells. When U937 cells were treated with 10(-8) M bufalin, the activity of JNK1 was markedly elevated 3 h after the start of treatment and remained so for 9 h. This activation of JNK and the induction of apoptosis by bufalin were suppressed by expression of antisense mRNA for MAPK kinase-1. c-Jun was translocated from the cytoplasm to the nucleus after treatment of U937 cells with bufalin. The transcriptional activity of AP-1 was transiently enhanced by the treatment with bufalin and this activation was suppressed by the expression of antisense mRNA for MAPK kinase-1. Both curcumin (1,7-bis[4-hydroxy-3-methoxy-phenyl]-1,6-heptadiene-3,5-dione), an inhibitor of the biosynthesis of AP-1, and the expression of dominant negative c-Jun inhibited the activation of AP-1 and the induction of apoptosis by bufalin. Expression of a constitutively active mutant form of MAPK kinase-1 induced the activation of AP-1 and subsequent apoptosis in U937 cells. These results suggest that the activation of AP-1 via a MAPK cascade that includes JNK is required for the induction of apoptosis by bufalin in U937 cells.[1]

References

  1. Activation of AP-1 is required for bufalin-induced apoptosis in human leukemia U937 cells. Watabe, M., Ito, K., Masuda, Y., Nakajo, S., Nakaya, K. Oncogene (1998) [Pubmed]
 
WikiGenes - Universities