microRNAs （miRNAs） constitute a unique class of endogenous small non-coding RNAs that regulate gene expression post-transcriptionally. Studies over the past decade have uncovered a r^curring paradigm in which miRNAs...microRNAs （miRNAs） constitute a unique class of endogenous small non-coding RNAs that regulate gene expression post-transcriptionally. Studies over the past decade have uncovered a r^curring paradigm in which miRNAs are key regulators of cellular behavior under various physiological and pathological conditions. Most surprising is the recent observation that miRNAs have emerged as competent players in somatic cell reprogramming, suggesting an especially significant role for these small RNAs in cell fate settings. Here, we discuss the possible mechanisms underlying miRNA-mediated cell programming （i.e., the development and differentiation of embryonic stem cells） and reprogramming （i.e., turning somatic cells into pluripo- tent stem cells or other lineages）, and provide a ＂Helm＂ model of miRNAs in cell fate decision and conversion.展开更多
Although microbes primarily are single-cell organisms,they are not isolated individuals.Microbes use various means to communicate with one another.Based on the communication,microbes establish a social interaction wit...Although microbes primarily are single-cell organisms,they are not isolated individuals.Microbes use various means to communicate with one another.Based on the communication,microbes establish a social interaction with their neighbors in a specific ecological niche,and cooperative behaviors are normally performed to provide benefits on the population and species levels.In the microbiome era,in order to better understand the behaviors of microbes,deep understanding of the social communication between microbes hence becomes a key to interpret microbe behaviors.Here we summarize the molecular mechanisms that underlie the cell-to-cell communication in prokaryotic and eukaryotic microorganisms,the recent discoveries and novel technologies in understanding the interspecies and interkingdom communication,and discuss new concepts of the sociomicrobiology.展开更多
We have previously developed bare narrow-bore capillary chromatography. In this work, high-performance DNA separation was realized for a size range of 10–800 base pairs(bp) utilizing bare narrow-bore capillary chroma...We have previously developed bare narrow-bore capillary chromatography. In this work, high-performance DNA separation was realized for a size range of 10–800 base pairs(bp) utilizing bare narrow-bore capillary chromatography with 750 nm- radius capillaries. Separation behavior of double-stranded DNA(ds DNA) fragments was investigated over a range of eluent concentrations and elution pressures. DNA molecules were hydrodynamically separated in a size-dependent manner in free solution without any sieving matrices, with the longer fragments being eluted out from the capillary earlier. It was found that the eluent concentration variously influenced the transport behavior for different-sized DNA fragments depending upon the configuration of DNA molecules and the association of counterions. Ionic strength of the solutions strongly impacted DNA persistence length. Enhanced elution pressure could shorten analysis time with a slight loss in resolution. Excellent efficiency of two million theoretical plates per meter was achieved, which indicates the enormous potential of bare narrow-bore capillary chromatography for the analysis of DNA fragments. These findings would be useful in understanding the transport behavior of DNA fragments in confined dimensions for chromatography in free solution.展开更多
In this study, the role of melanopsin-expressing retinal ganglion cells （mRGCs） in the glaucoma-induced depressive behavioral response pattern was investigated. The CFP-D2 transgenic glaucoma animal model from five ...In this study, the role of melanopsin-expressing retinal ganglion cells （mRGCs） in the glaucoma-induced depressive behavioral response pattern was investigated. The CFP-D2 transgenic glaucoma animal model from five age groups was used in this study. Immunohistochemical labeling, quantitative analysis of mRGC morphology, open field test （OFT）, and statistical analysis were used. In comparison with C57 BL/6 mice, the age-matched CFP-D2 mice had significantly elevated intraocular pressure （lOP）. We observed parallel morphological changes in the retina, including a reduction in the density of cyan fluorescent protein- （CFP） expressing cells （cells mm^-2 at 2 months of age, 1309±26; 14 months, 878±30, P〈0.001）, mRGCs （2 months, 48_＋3; 14 months, 19±4, P〈0.001）, Brn3b-expressing RGCs （2 months, 1283±80; 14 months, 950±31, P〈0.001）, Brn-3b expressing mRGCs （5 months, 50.17%±5.5%; 14 months, 12.61%±3.8%, P〈0.001）, and reduction in the dendritic field size of mRGCs （mm^2 at 2 months, 0.077±0.015; 14 months, 0.065±0.015, P〈0.05）. CFP-D2 mice had hyperactive locomotor activity patterns based on OFT findings of the total distance traveled, number of entries into the center, and time spent in the center of the testing apparatus. The glaucoma induced hyperactive response pattern could be associated with dysfunctional mRGCs, most likely Brn-3b-positive mRGCs in CFP-D2 mice.展开更多
基金supported by the National Natural Science Foundation of China(31200593,31230042,81070589)the Guangdong Natural Science Foundation(S2011040001760)+1 种基金the Fundamental Research Funds for the Central Universities(13lgpy40)the National Basic Research Program of China(2011CB811300)
文摘microRNAs （miRNAs） constitute a unique class of endogenous small non-coding RNAs that regulate gene expression post-transcriptionally. Studies over the past decade have uncovered a r^curring paradigm in which miRNAs are key regulators of cellular behavior under various physiological and pathological conditions. Most surprising is the recent observation that miRNAs have emerged as competent players in somatic cell reprogramming, suggesting an especially significant role for these small RNAs in cell fate settings. Here, we discuss the possible mechanisms underlying miRNA-mediated cell programming （i.e., the development and differentiation of embryonic stem cells） and reprogramming （i.e., turning somatic cells into pluripo- tent stem cells or other lineages）, and provide a ＂Helm＂ model of miRNAs in cell fate decision and conversion.
基金supported by the National Natural Science Foundation of China(31571288)CAS Interdisciplinary Innovation Team and the Newton Advanced Fellowship(NA140085)from the Royal Society
文摘Although microbes primarily are single-cell organisms,they are not isolated individuals.Microbes use various means to communicate with one another.Based on the communication,microbes establish a social interaction with their neighbors in a specific ecological niche,and cooperative behaviors are normally performed to provide benefits on the population and species levels.In the microbiome era,in order to better understand the behaviors of microbes,deep understanding of the social communication between microbes hence becomes a key to interpret microbe behaviors.Here we summarize the molecular mechanisms that underlie the cell-to-cell communication in prokaryotic and eukaryotic microorganisms,the recent discoveries and novel technologies in understanding the interspecies and interkingdom communication,and discuss new concepts of the sociomicrobiology.
基金supported by the National Natural Science Foundation of China(21275014)the Excellent Young Scientists Fund of NSFC(21322501)+3 种基金the Importation and Development of High-Caliber Talents Project of Beijing Municipal Institutions(CIT&TCD20140309)the Program for New Century Excellent Talents in University(NCET-12-0603)the Beijing Natural Science Foundation ProgramScientific Research Key Program of Beijing Municipal Commission of Education(KZ201310005001)
文摘We have previously developed bare narrow-bore capillary chromatography. In this work, high-performance DNA separation was realized for a size range of 10–800 base pairs(bp) utilizing bare narrow-bore capillary chromatography with 750 nm- radius capillaries. Separation behavior of double-stranded DNA(ds DNA) fragments was investigated over a range of eluent concentrations and elution pressures. DNA molecules were hydrodynamically separated in a size-dependent manner in free solution without any sieving matrices, with the longer fragments being eluted out from the capillary earlier. It was found that the eluent concentration variously influenced the transport behavior for different-sized DNA fragments depending upon the configuration of DNA molecules and the association of counterions. Ionic strength of the solutions strongly impacted DNA persistence length. Enhanced elution pressure could shorten analysis time with a slight loss in resolution. Excellent efficiency of two million theoretical plates per meter was achieved, which indicates the enormous potential of bare narrow-bore capillary chromatography for the analysis of DNA fragments. These findings would be useful in understanding the transport behavior of DNA fragments in confined dimensions for chromatography in free solution.
基金supported by the National Basic Research Program of China (2009CB320900 to Pu MingLiang,2011CB510206 to Pu MingLiangand Gao Jie)National Natural Science Foundation of China(30831160516 to Pu MingLiang)+2 种基金NIH EY04067 (N.C. Brecha)VAMerit Review (N.C. Brecha).supported by a summer fellowship from the PKU-UCLA Joint Research Institute
文摘In this study, the role of melanopsin-expressing retinal ganglion cells （mRGCs） in the glaucoma-induced depressive behavioral response pattern was investigated. The CFP-D2 transgenic glaucoma animal model from five age groups was used in this study. Immunohistochemical labeling, quantitative analysis of mRGC morphology, open field test （OFT）, and statistical analysis were used. In comparison with C57 BL/6 mice, the age-matched CFP-D2 mice had significantly elevated intraocular pressure （lOP）. We observed parallel morphological changes in the retina, including a reduction in the density of cyan fluorescent protein- （CFP） expressing cells （cells mm^-2 at 2 months of age, 1309±26; 14 months, 878±30, P〈0.001）, mRGCs （2 months, 48_＋3; 14 months, 19±4, P〈0.001）, Brn3b-expressing RGCs （2 months, 1283±80; 14 months, 950±31, P〈0.001）, Brn-3b expressing mRGCs （5 months, 50.17%±5.5%; 14 months, 12.61%±3.8%, P〈0.001）, and reduction in the dendritic field size of mRGCs （mm^2 at 2 months, 0.077±0.015; 14 months, 0.065±0.015, P〈0.05）. CFP-D2 mice had hyperactive locomotor activity patterns based on OFT findings of the total distance traveled, number of entries into the center, and time spent in the center of the testing apparatus. The glaucoma induced hyperactive response pattern could be associated with dysfunctional mRGCs, most likely Brn-3b-positive mRGCs in CFP-D2 mice.
