Objective: To discuss the relationship between hypercholesterolemic disease and the functional and structural changes of Sphincter of Oddi (SO) by the study of effect of Cholesterol Liposome (CL) on structural and qua...Objective: To discuss the relationship between hypercholesterolemic disease and the functional and structural changes of Sphincter of Oddi (SO) by the study of effect of Cholesterol Liposome (CL) on structural and quantitative changes of SO cells. Methods: Rabbit SO was isolated for primary cell culture and subculture. After subcultured with different concentration of CL culture medium for 20 h, the structural and quantitative changes of SO cells were analyzed and detected by MTT-test, flow cytometer (FCM), electronic microscope and electrophoresis technique respectively. Results: CL contributed a prominent stimulus to SO cells proliferation at middle concentration (<0. 5 - 0. 8 mg/ml), which could be confirmed by FCM analysis which indicated the number of SO cells in S-phase increasing remarkably; however, high concentration of CL inhibited SO cells' proliferation (>1. 0 mg/ml) and induced apoptosis of SO cells. Swelled mitochondria and dilated endoplasmic reticulum as well as disjoined and diminished microfilaments were found in SO cells by electronic microscopy. The content of SO cells actin decreased with the increment of cholesterol concentration. There was a significant difference of actin content between CL groups and control group (P<0. 05). Conclusion: CL may change SO cell membrane's function, organelle's structure and especially the quantity and configuration of microfilaments, at the same time, CL at different concentration can induce changes of SO cells cycle and lead to different changes in the number of SO cells.展开更多
Cells are crowded microenvironments filled with macromolecules undergoing constant phys- ical and chemical interactions. The physicochemical makeup of the cells aff）cts various cellular responses, determines cell-cel...Cells are crowded microenvironments filled with macromolecules undergoing constant phys- ical and chemical interactions. The physicochemical makeup of the cells aff）cts various cellular responses, determines cell-cell interactions and influences cell decisions. Chemical and physical properties diff）r between cells and within cells. Moreover, these properties are subject to dynamic changes in response to environmental signals, which often demand adjustments in the chemical or physical states of intracellular molecules. Indeed, cellular responses such as gene expression rely on the faithful relay of information from the outside to the inside of the cell, a process terrned signal transduction. The signal often traverses a complex path across subcellular spaces with variable physical chemistry, sometimes even influencing it. Understanding the molecular states of such signaling molecules and their intracellular environments is vital to our understanding of the cell. Exploring such intricate spaces is possible today largely because of experimental and theoretical tools. Here, we focus on one tool that is commonly used in chemical physics studies light. We summarize recent work which uses light to both visualize the cellular environment and also control intracel- lular processes along the axis of signal transduction. We highlight recent accomplishments in optical microscopy and optogenetics, an emerging experimental strategy which utilizes light to control the molecular processes in live cells. We believe that optogenetics lends un- precedented spatiotemporal precision to the manipulation of physicochemical properties in biological contexts. We hope to use this work to demonstrate new opportunities for chemical physicists who are interested in pursuing biological and biomedical questions.展开更多
Hepatitis B virus(HBV) infection is one of the major problems that threatens global health. There have been many studies on HBV, but the relationship between HBV and host factors is largely unexplored and more studies...Hepatitis B virus(HBV) infection is one of the major problems that threatens global health. There have been many studies on HBV, but the relationship between HBV and host factors is largely unexplored and more studies are needed to clarify these interactions. Filamin B is an actin-binding protein that acts as a cytoskeleton protein, and it is involved in cell development and several signaling pathways. In this study, we showed that filamin B interacted with HBV core protein,and the interaction promoted HBV replication. The interaction between filamin B and core protein was observed in HEK293T, Huh7 and HepG2 cell lines by co-immunoprecipitation and co-localization immnofluoresence. Overexpression of filamin B increased the levels of HBV total RNAs and pre-genome RNA(pg RNA), and improved the secretion level of hepatitis B surface antigen(HBsAg) and hepatitis B e antigen(HBeAg). In contrast, filamin B knockdown inhibited HBV replication, decreased the level of HBV total RNAs and pgRNA, and reduced the secretion level of HBsAg and HBeAg. In addition, we found that filamin B and core protein may interact with each other via four blocks of argentine residues at the C-terminus of core protein. In conclusion, we identify filamin B as a novel host factor that can interact with core protein to promote HBV replication in hepatocytes. Our study provides new insights into the relationship between HBV and host factors and may provide new strategies for the treatment of HBV infection.展开更多
Dear Editor,Actins are a family of essential cytoskeletal proteins involved in nearly all cellular processes（Lambrechts et al.,2004）.Of the six human genes that encode actins,only ACTG1and ACTB are ubiquitously expr...Dear Editor,Actins are a family of essential cytoskeletal proteins involved in nearly all cellular processes（Lambrechts et al.,2004）.Of the six human genes that encode actins,only ACTG1and ACTB are ubiquitously expressed.ACTG1（OMIM#604717）,which is linked to the DFNA20/26 locus,wasidentified in autosomal dominant, non-syndromic hearing loss （NSHL） cases （Baek et al., 2012; Liu et al., 2008; Park et al., 2013; Yuan et al., 2016）. In addition, some ACTG1 （OMIM #614583） mutations are associated with Baraitser-Winter syndrome, which is characterized by developmental delay, facial dysmorphologies, brain malformations, colobomas, and variable hearing loss （Riviere et al., 2012）.展开更多
文摘Objective: To discuss the relationship between hypercholesterolemic disease and the functional and structural changes of Sphincter of Oddi (SO) by the study of effect of Cholesterol Liposome (CL) on structural and quantitative changes of SO cells. Methods: Rabbit SO was isolated for primary cell culture and subculture. After subcultured with different concentration of CL culture medium for 20 h, the structural and quantitative changes of SO cells were analyzed and detected by MTT-test, flow cytometer (FCM), electronic microscope and electrophoresis technique respectively. Results: CL contributed a prominent stimulus to SO cells proliferation at middle concentration (<0. 5 - 0. 8 mg/ml), which could be confirmed by FCM analysis which indicated the number of SO cells in S-phase increasing remarkably; however, high concentration of CL inhibited SO cells' proliferation (>1. 0 mg/ml) and induced apoptosis of SO cells. Swelled mitochondria and dilated endoplasmic reticulum as well as disjoined and diminished microfilaments were found in SO cells by electronic microscopy. The content of SO cells actin decreased with the increment of cholesterol concentration. There was a significant difference of actin content between CL groups and control group (P<0. 05). Conclusion: CL may change SO cell membrane's function, organelle's structure and especially the quantity and configuration of microfilaments, at the same time, CL at different concentration can induce changes of SO cells cycle and lead to different changes in the number of SO cells.
基金supported by the School of Molecular Cell Biology at the University of Illinois at Urbana-Champaign
文摘Cells are crowded microenvironments filled with macromolecules undergoing constant phys- ical and chemical interactions. The physicochemical makeup of the cells aff）cts various cellular responses, determines cell-cell interactions and influences cell decisions. Chemical and physical properties diff）r between cells and within cells. Moreover, these properties are subject to dynamic changes in response to environmental signals, which often demand adjustments in the chemical or physical states of intracellular molecules. Indeed, cellular responses such as gene expression rely on the faithful relay of information from the outside to the inside of the cell, a process terrned signal transduction. The signal often traverses a complex path across subcellular spaces with variable physical chemistry, sometimes even influencing it. Understanding the molecular states of such signaling molecules and their intracellular environments is vital to our understanding of the cell. Exploring such intricate spaces is possible today largely because of experimental and theoretical tools. Here, we focus on one tool that is commonly used in chemical physics studies light. We summarize recent work which uses light to both visualize the cellular environment and also control intracel- lular processes along the axis of signal transduction. We highlight recent accomplishments in optical microscopy and optogenetics, an emerging experimental strategy which utilizes light to control the molecular processes in live cells. We believe that optogenetics lends un- precedented spatiotemporal precision to the manipulation of physicochemical properties in biological contexts. We hope to use this work to demonstrate new opportunities for chemical physicists who are interested in pursuing biological and biomedical questions.
基金supported by the Postdoctoral Science Foundation of China
文摘Hepatitis B virus(HBV) infection is one of the major problems that threatens global health. There have been many studies on HBV, but the relationship between HBV and host factors is largely unexplored and more studies are needed to clarify these interactions. Filamin B is an actin-binding protein that acts as a cytoskeleton protein, and it is involved in cell development and several signaling pathways. In this study, we showed that filamin B interacted with HBV core protein,and the interaction promoted HBV replication. The interaction between filamin B and core protein was observed in HEK293T, Huh7 and HepG2 cell lines by co-immunoprecipitation and co-localization immnofluoresence. Overexpression of filamin B increased the levels of HBV total RNAs and pre-genome RNA(pg RNA), and improved the secretion level of hepatitis B surface antigen(HBsAg) and hepatitis B e antigen(HBeAg). In contrast, filamin B knockdown inhibited HBV replication, decreased the level of HBV total RNAs and pgRNA, and reduced the secretion level of HBsAg and HBeAg. In addition, we found that filamin B and core protein may interact with each other via four blocks of argentine residues at the C-terminus of core protein. In conclusion, we identify filamin B as a novel host factor that can interact with core protein to promote HBV replication in hepatocytes. Our study provides new insights into the relationship between HBV and host factors and may provide new strategies for the treatment of HBV infection.
基金supported by the National Natural Science Foundation of China(81530032)the National Key Basic Research Program of China(2014CB943001)
文摘Dear Editor,Actins are a family of essential cytoskeletal proteins involved in nearly all cellular processes（Lambrechts et al.,2004）.Of the six human genes that encode actins,only ACTG1and ACTB are ubiquitously expressed.ACTG1（OMIM#604717）,which is linked to the DFNA20/26 locus,wasidentified in autosomal dominant, non-syndromic hearing loss （NSHL） cases （Baek et al., 2012; Liu et al., 2008; Park et al., 2013; Yuan et al., 2016）. In addition, some ACTG1 （OMIM #614583） mutations are associated with Baraitser-Winter syndrome, which is characterized by developmental delay, facial dysmorphologies, brain malformations, colobomas, and variable hearing loss （Riviere et al., 2012）.
