The seven members of the signal transducer and activator of transcription （STAT） family of transcription factors are activated in response to many different cytokines and growth factors by phosphorylation of specifi...The seven members of the signal transducer and activator of transcription （STAT） family of transcription factors are activated in response to many different cytokines and growth factors by phosphorylation of specific tyrosine residues. The STAT1 and STAT3 genes are specific targets of activated STATs 1 and 3, respectively, resulting in large increases in the levels of these unphosphorylated STATs （U-STATs） in response to the interferons （STAT1） or ligands that active gpl30, such as IL-6 （STAT3）. U-STATs drive gene expression by novel mechanisms distinct from those used by phosphorylated STAT （P-STAT） dimers. In this review, we discuss the roles of U-STATs in transcription and regulation of gene expression.展开更多
The family members of the mitogen-activated protein (MAP) kinases mediate a wide variety of cellular behaviors in response to extracellular stimuli. One of the four main sub-groups, the p38 group of MAP kinases, serve...The family members of the mitogen-activated protein (MAP) kinases mediate a wide variety of cellular behaviors in response to extracellular stimuli. One of the four main sub-groups, the p38 group of MAP kinases, serve as a nexus for signal transduction and play a vital role in numerous biological processes. In this review, we highlight the known characteristics and components of the p38 pathway along with the mechanism and consequences of p38 activation. We focus on the role of p38 as a signal transduction mediator and examine the evidence linking p38 to inflammation, cell cycle, cell death, development, cell differentiation, senescence and tumorigenesis in specific cell types. Upstream and downstream components of p38 are described and questions remaining to be answered are posed. Finally, we propose several directions for future research on p38.展开更多
Phenolics,as the main bioactive compounds in tea,have been suggested to have potential in the prevention of various human diseases.However,little is known about phenolics and their bioactivity in Zhangping Narcissue t...Phenolics,as the main bioactive compounds in tea,have been suggested to have potential in the prevention of various human diseases.However,little is known about phenolics and their bioactivity in Zhangping Narcissue tea cake which is considered the most special kind of oolong tea.To unveil its bioactivity,three phenolic-enriched extracts were obtained from Zhangping Narcissue tea cake using ethyl acetate,n-butanol,and water.Their main chemical compositions and in vitro bioactivity were analyzed by high-performance liquid chromatography(HPLC)and ultraperformance liquid chromatography-mass spectrometry(UPLC-MS).The ethyl acetate fraction(ZEF)consisted of higher content of phenolics,flavonoids,procyanidins,and catechin monomers(including epigallocatechin gallate(EGCG),epicatechin gallate(ECG),and gallocatechin gallate(GCG))than n-butanol fraction(ZBF)and water fraction(ZWF).ZEF exhibited the strongest antioxidant capacity in vitro due to its abundant bioactive compounds.This was validated by Pearson correlation and hierarchical clustering analyses.ZEF also showed a remarkable inhibition on the growth,migration,and invasion of 4T1 murine breast cancer cells.展开更多
文摘The seven members of the signal transducer and activator of transcription （STAT） family of transcription factors are activated in response to many different cytokines and growth factors by phosphorylation of specific tyrosine residues. The STAT1 and STAT3 genes are specific targets of activated STATs 1 and 3, respectively, resulting in large increases in the levels of these unphosphorylated STATs （U-STATs） in response to the interferons （STAT1） or ligands that active gpl30, such as IL-6 （STAT3）. U-STATs drive gene expression by novel mechanisms distinct from those used by phosphorylated STAT （P-STAT） dimers. In this review, we discuss the roles of U-STATs in transcription and regulation of gene expression.
文摘The family members of the mitogen-activated protein (MAP) kinases mediate a wide variety of cellular behaviors in response to extracellular stimuli. One of the four main sub-groups, the p38 group of MAP kinases, serve as a nexus for signal transduction and play a vital role in numerous biological processes. In this review, we highlight the known characteristics and components of the p38 pathway along with the mechanism and consequences of p38 activation. We focus on the role of p38 as a signal transduction mediator and examine the evidence linking p38 to inflammation, cell cycle, cell death, development, cell differentiation, senescence and tumorigenesis in specific cell types. Upstream and downstream components of p38 are described and questions remaining to be answered are posed. Finally, we propose several directions for future research on p38.
基金Project supported by the Science and Technology Department of Guangdong Province,China(No.2016B090918118)
文摘Phenolics,as the main bioactive compounds in tea,have been suggested to have potential in the prevention of various human diseases.However,little is known about phenolics and their bioactivity in Zhangping Narcissue tea cake which is considered the most special kind of oolong tea.To unveil its bioactivity,three phenolic-enriched extracts were obtained from Zhangping Narcissue tea cake using ethyl acetate,n-butanol,and water.Their main chemical compositions and in vitro bioactivity were analyzed by high-performance liquid chromatography(HPLC)and ultraperformance liquid chromatography-mass spectrometry(UPLC-MS).The ethyl acetate fraction(ZEF)consisted of higher content of phenolics,flavonoids,procyanidins,and catechin monomers(including epigallocatechin gallate(EGCG),epicatechin gallate(ECG),and gallocatechin gallate(GCG))than n-butanol fraction(ZBF)and water fraction(ZWF).ZEF exhibited the strongest antioxidant capacity in vitro due to its abundant bioactive compounds.This was validated by Pearson correlation and hierarchical clustering analyses.ZEF also showed a remarkable inhibition on the growth,migration,and invasion of 4T1 murine breast cancer cells.
