Expression of mdr-1 is complex and highly regulated. Several lines of evidence indirectly suggest that transcription factor c-Jun may negatively regulate human mdr-1 gene expression. We recently found that salvicine, a novel topoisomerase II inhibitor, is cytotoxic for multidrug resistance (MDR) tumor cells and down-regulates mdr-1 expression in MDR K562/A02 cells. Salvicine also stimulates a s...

Jun and Fos nuclear oncoproteins form a complex that regulates transcription from promoters containing activator protein AP-1 binding sites. The leucine-zipper and basic-region domains of both Fos and Jun are necessary for formation of the heterodimer that binds to DNA. Reciprocal mutations in the basic region of Fos or Jun can influence the binding of the heterodimer to DNA, implying a symmetr...

Damage to the axons of adult sensory neurons results in massively increased expression of the protooncogene c-jun both in neurons and in the associated Schwann cells. The role of growth factors and axon contact in mediating this expression was investigated in dissociated cultures of adult sensory neurons and glial cells that expressed c-jun within 24 hr of plating. Trk, trkB, and trkC growth fa...

The proto-oncogene c-Jun plays essential roles in various cellular processes, including cell proliferation, cell differentiation, and cellular apoptosis. Enormous efforts have been made to understand the mechanisms regulating c-Jun activation. The males absent on the first (MOF)-containing non-specific lethal (NSL) complex has been shown to positively regulate gene expression. However, the biol...

Radiation-induced normal brain injury is associated with acute and/or chronic inflammatory responses, and has been a major concern in radiotherapy. Recent studies suggest that microglial activation is a potential contributor to chronic inflammatory responses following irradiation; however, the molecular mechanism underlying the response of microglia to radiation is poorly understood. c-Jun, a c...

Cerebellar granule neurons die by apoptosis when deprived of survival signals. This death can be blocked by inhibitors of transcription or protein synthesis, suggesting that new gene expression is required. Here we show that c-jun mRNA and protein levels increase rapidly after survival signal withdrawal and that transfection of the neurons with an expression vector for a c-Jun dominant negative...

Ocular hypertension, a major risk factor for glaucoma, is thought to trigger glaucomatous neurodegeneration through injury to retinal ganglion cell (RGC) axons. The molecular signaling pathway leading from ocular hypertension to RGC degeneration, however, is not well defined. JNK signaling, a component of the mitogen-activated protein kinase (MAPK) family, and its canonical target, the transcri...

Sever-Chroneos, Zvjezdana, Cindy J. Bachurski, Cong Yan, and Jeffrey A. Whitsett. Regulation of mouse SP-B gene promoter by AP-1 family members. Am. J. Physiol. 277 (Lung Cell. Mol. Physiol. 21): L79–L88, 1999.—The regulatory role of activator protein-1 (AP-1) family members in mouse surfactant protein (SP) B (mSP-B) promoter function was assessed in the mouse lung epithelial cell line MLE-15. ...

Objective: To investigate the anti-inflammatory effects of total flavonoids from Saussurea involucrata on lipopolysaccharides (LPS)-stimulated murine RAW264.7 macrophages and explore its underlying mechanism action. Methods: Total were extracted using chromatographic column method. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. The producti...

Gang Li, Tian-Lei Zheng, Xiao-Ling Chi, Yong-Fen Zhu, Jin-Jun Chen, Liang Xu, Jun-Ping Shi, Xiao-Dong Wang, Wei-Guo Zhao, Christopher D. Byrne, Giovanni Targher, Rafael S. Rios, Ou-Yang Huang, Liang-Jie Tang, Shi-Jin Zhang, Shi Geng, Huan-Ming Xiao, Sui-Dan Rui Ming-Hua Zheng