Sensing and responding to our environment requires functional neurons that act in concert. Neuronal cell loss resulting from degenerative diseases cannot be replaced in humans, causing a functional impairment to integ...Sensing and responding to our environment requires functional neurons that act in concert. Neuronal cell loss resulting from degenerative diseases cannot be replaced in humans, causing a functional impairment to integrate and/or respond to sensory cues. In contrast, zebrafish（Danio rerio） possess an endogenous capacity to regenerate lost neurons. Here, we will focus on the processes that lead to neuronal regeneration in the zebrafish retina. Dying retinal neurons release a damage signal, tumor necrosis factor α, which induces the resident radial glia, the Müller glia, to reprogram and re-enter the cell cycle. The Müller glia divide asymmetrically to produce a Müller glia that exits the cell cycle and a neuronal progenitor cell. The arising neuronal progenitor cells undergo several rounds of cell divisions before they migrate to the site of damage to differentiate into the neuronal cell types that were lost. Molecular and immunohistochemical studies have predominantly provided insight into the mechanisms that regulate retinal regeneration. However, many processes during retinal regeneration are dynamic and require live-cell imaging to fully discern the underlying mechanisms. Recently, a multiphoton imaging approach of adult zebrafish retinal cultures was developed. We will discuss the use of live-cell imaging, the currently available tools and those that need to be developed to advance our knowledge on major open questions in the field of retinal regeneration.展开更多
Cells in the body are exposed to physiological and pathophysiological stimuli that encompass both chemical and mechanical factors,which coordinately modulate cellular functions. Compared to the large amount of informa...Cells in the body are exposed to physiological and pathophysiological stimuli that encompass both chemical and mechanical factors,which coordinately modulate cellular functions. Compared to the large amount of information on cellular re-展开更多
Imaging proteins with high resolution is crucial for studying cellular physiology and pathology.Fluorescence imaging is a privileged method to visualize proteins with subcellular precision in live cells.In recent year...Imaging proteins with high resolution is crucial for studying cellular physiology and pathology.Fluorescence imaging is a privileged method to visualize proteins with subcellular precision in live cells.In recent years,there has been a tremendous advance in the field of fluorescent dyes that are optically more sophisticated than genetically-encodable fluorescent proteins.In this review,we aim to discuss modern bioconjugation methods to specifically incorporate these dyes into protein-of-interests.We focus on advances in live-cell labeling strategies and fluorescent probes,especially the HaloTag,SNAP-tag,TMP-tag,and unnatural amino acid systems and their applications.These protein labeling methods,along with cutting-edge dyes and novel microscopy methods,have become the infrastructure for biological research in the era of super-resolution imaging.展开更多
Currently, the application of synthetic biology to artificially manipulate and utilize organisms for the synthesis of desired products such as nanomaterials with excellent fluorescence properties is attracting conside...Currently, the application of synthetic biology to artificially manipulate and utilize organisms for the synthesis of desired products such as nanomaterials with excellent fluorescence properties is attracting considerable attention. However, it is still difficult to obtain designed products efficiently due to insufficient knowledge of the biosynthetic mechanisms. The thioredoxin(TRX) and glutathione(GSH) pathways are generally conserved thiol-reductase systems that protect organisms from oxidative stress and are involved in selenium(Se) metabolism. In this study, we revealed the pivotal role of cytoplasmic TRX pathway in regulating the metabolism of Na_(2)SeO_(3) during the live-cell synthesis of cadmium-selenium quantum dots(Cd Se QDs) in Saccharomyces cerevisiae by regulating the expression level of genes related to TRX pathway and measuring the intracellular content of selenocysteine(Se Cys). The determination of Se Cys metabolism in yeast with GSH pathway-related genes deleted demonstrated that the TRX pathway played a more significant role in Se Cys metabolism than GSH pathway. A 6.4-fold enhancement in the synthetic yield of Cd Se QDs was achieved through the overexpression of TRX pathway-related genes,improvement of synthetic procedure, and supplementation of GSH based on the understanding of biological metabolism.Exploring the mechanism of CdSe QDs live-cell synthesis facilitates the precise manipulation of biological processes for the synthesis of inorganic nanomaterials.展开更多
In plant cells, the Golgi apparatus consists of numerous stacks that, in turn, are composed of several flattened cisternae with a clear cis-to-trans polarity. During normal functioning within living cells, this unusua...In plant cells, the Golgi apparatus consists of numerous stacks that, in turn, are composed of several flattened cisternae with a clear cis-to-trans polarity. During normal functioning within living cells, this unusual organelle displays a wide range of dynamic behaviors such as whole stack motility, constant membrane flux through the cisternae, and Golgi enzyme recycling through the ER. In order to further investigate various aspects of Golgi stack dynamics and integrity, we co-expressed pairs of established Golgi markers in tobacco BY-2 cells to distinguish sub-compartments of the Golgi during monensin treatments, movement, and brefeldin A （BFA）-induced disassembly. A combination of cis and trans markers revealed that Golgi stacks remain intact as they move through the cytoplasm. The Golgi stack orientation during these movements showed a slight preference for the cis side moving ahead, but trans cisternae were also found at the leading edge. During BFA treatments, the different sub-compartments of about half of the observed stacks fused with the ER sequentially; however, no consistent order could be detected. In contrast, the ionophore monensin resulted in swelling of trans cisternae while medial and particularly cis cisternae were mostly unaffected. Our results thus demonstrate a re- markable equivalence of the different cisternae with respect to movement and BFA-induced fusion with the ER. In addi- tion, we propose that a combination of dual-label fluorescence microscopy and drug treatments can provide a simple alternative approach to the determination of protein localization to specific Golgi sub-compartments.展开更多
The dynamic behavior of organelles is essential for plant survival under various environmental conditions. Plant organelles, with various functions,migrate along actin filaments and contact other types of organelles, ...The dynamic behavior of organelles is essential for plant survival under various environmental conditions. Plant organelles, with various functions,migrate along actin filaments and contact other types of organelles, leading to physical interactions at a specific site called the membrane contact site. Recent studies have revealed the importance of physical interactions in maintaining efficient metabolite flow between organelles.In this review, we first summarize peroxisome function under different environmental conditions and growth stages to understand organelle interactions. We then discuss current knowledge regarding the interactions between peroxisome and other organelles, i.e., the oil bodies, chloroplast, and mitochondria from the perspective of metabolic and physiological regulation, with reference to various organelle interactions and techniques for estimating organelle interactions occurring in plant cells.展开更多
In recent years, stem cells have been a focal point in research designed to evaluate the efficacy of ophthalmologic therapies, specifically those for corneal conditions. The corneal epithelium is one of the few region...In recent years, stem cells have been a focal point in research designed to evaluate the efficacy of ophthalmologic therapies, specifically those for corneal conditions. The corneal epithelium is one of the few regions of the body that maintains itself using a residual stem cell population within the adjacent limbus. Stem cell movement has additionally captivated the minds of researchers due to its potential application in different body regions. The cornea is a viable model for varying methods to track stem cell migratory patterns, such as lineage tracing and live imaging from the limbus. These developments have the potential to pave the way for future therapies designed to ensure the continuous regeneration of the corneal epithelium following injury via the limbal stem cell niche. This literature review aims to analyze the various methods of imaging used to understand the limbal stem cell niche and possible future directions that might be useful to consider for the better treatment and prevention of disorders of the cornea and corneal epithelium. .展开更多
基金supported by NIH-NEI grants to DRH(R01-EY018417,R01-EY024519)the Center for Zebrafish Research,University of Notre Dame,USA
文摘Sensing and responding to our environment requires functional neurons that act in concert. Neuronal cell loss resulting from degenerative diseases cannot be replaced in humans, causing a functional impairment to integrate and/or respond to sensory cues. In contrast, zebrafish（Danio rerio） possess an endogenous capacity to regenerate lost neurons. Here, we will focus on the processes that lead to neuronal regeneration in the zebrafish retina. Dying retinal neurons release a damage signal, tumor necrosis factor α, which induces the resident radial glia, the Müller glia, to reprogram and re-enter the cell cycle. The Müller glia divide asymmetrically to produce a Müller glia that exits the cell cycle and a neuronal progenitor cell. The arising neuronal progenitor cells undergo several rounds of cell divisions before they migrate to the site of damage to differentiate into the neuronal cell types that were lost. Molecular and immunohistochemical studies have predominantly provided insight into the mechanisms that regulate retinal regeneration. However, many processes during retinal regeneration are dynamic and require live-cell imaging to fully discern the underlying mechanisms. Recently, a multiphoton imaging approach of adult zebrafish retinal cultures was developed. We will discuss the use of live-cell imaging, the currently available tools and those that need to be developed to advance our knowledge on major open questions in the field of retinal regeneration.
基金supported in part by grants from NIH HL098472, CA139272, NS063405NSF CBET0846429,CMMI0800870the Wallace H Coulter Foundation,and the Beckman Laser Institute Inc
文摘Cells in the body are exposed to physiological and pathophysiological stimuli that encompass both chemical and mechanical factors,which coordinately modulate cellular functions. Compared to the large amount of information on cellular re-
基金supported by the National Natural Science Foundation of China(Project 31971375)the Beijing Municipal Science&Technology Commission(Project Z221100003422013).
文摘Imaging proteins with high resolution is crucial for studying cellular physiology and pathology.Fluorescence imaging is a privileged method to visualize proteins with subcellular precision in live cells.In recent years,there has been a tremendous advance in the field of fluorescent dyes that are optically more sophisticated than genetically-encodable fluorescent proteins.In this review,we aim to discuss modern bioconjugation methods to specifically incorporate these dyes into protein-of-interests.We focus on advances in live-cell labeling strategies and fluorescent probes,especially the HaloTag,SNAP-tag,TMP-tag,and unnatural amino acid systems and their applications.These protein labeling methods,along with cutting-edge dyes and novel microscopy methods,have become the infrastructure for biological research in the era of super-resolution imaging.
基金supported by the National Natural Science Foundation of China (22293030, 22293032)the National Key Research and Development Program of China (2019YFA0210100)the Fundamental Research Funds for the Central Universities of China (63211023)。
文摘Currently, the application of synthetic biology to artificially manipulate and utilize organisms for the synthesis of desired products such as nanomaterials with excellent fluorescence properties is attracting considerable attention. However, it is still difficult to obtain designed products efficiently due to insufficient knowledge of the biosynthetic mechanisms. The thioredoxin(TRX) and glutathione(GSH) pathways are generally conserved thiol-reductase systems that protect organisms from oxidative stress and are involved in selenium(Se) metabolism. In this study, we revealed the pivotal role of cytoplasmic TRX pathway in regulating the metabolism of Na_(2)SeO_(3) during the live-cell synthesis of cadmium-selenium quantum dots(Cd Se QDs) in Saccharomyces cerevisiae by regulating the expression level of genes related to TRX pathway and measuring the intracellular content of selenocysteine(Se Cys). The determination of Se Cys metabolism in yeast with GSH pathway-related genes deleted demonstrated that the TRX pathway played a more significant role in Se Cys metabolism than GSH pathway. A 6.4-fold enhancement in the synthetic yield of Cd Se QDs was achieved through the overexpression of TRX pathway-related genes,improvement of synthetic procedure, and supplementation of GSH based on the understanding of biological metabolism.Exploring the mechanism of CdSe QDs live-cell synthesis facilitates the precise manipulation of biological processes for the synthesis of inorganic nanomaterials.
文摘In plant cells, the Golgi apparatus consists of numerous stacks that, in turn, are composed of several flattened cisternae with a clear cis-to-trans polarity. During normal functioning within living cells, this unusual organelle displays a wide range of dynamic behaviors such as whole stack motility, constant membrane flux through the cisternae, and Golgi enzyme recycling through the ER. In order to further investigate various aspects of Golgi stack dynamics and integrity, we co-expressed pairs of established Golgi markers in tobacco BY-2 cells to distinguish sub-compartments of the Golgi during monensin treatments, movement, and brefeldin A （BFA）-induced disassembly. A combination of cis and trans markers revealed that Golgi stacks remain intact as they move through the cytoplasm. The Golgi stack orientation during these movements showed a slight preference for the cis side moving ahead, but trans cisternae were also found at the leading edge. During BFA treatments, the different sub-compartments of about half of the observed stacks fused with the ER sequentially; however, no consistent order could be detected. In contrast, the ionophore monensin resulted in swelling of trans cisternae while medial and particularly cis cisternae were mostly unaffected. Our results thus demonstrate a re- markable equivalence of the different cisternae with respect to movement and BFA-induced fusion with the ER. In addi- tion, we propose that a combination of dual-label fluorescence microscopy and drug treatments can provide a simple alternative approach to the determination of protein localization to specific Golgi sub-compartments.
基金supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT, KAKENHI Grant-in-Aid for Scientific Research on Innovative Areas to M.N.[No.22120007])a fund to M.N. from Wyeth Foundation
文摘The dynamic behavior of organelles is essential for plant survival under various environmental conditions. Plant organelles, with various functions,migrate along actin filaments and contact other types of organelles, leading to physical interactions at a specific site called the membrane contact site. Recent studies have revealed the importance of physical interactions in maintaining efficient metabolite flow between organelles.In this review, we first summarize peroxisome function under different environmental conditions and growth stages to understand organelle interactions. We then discuss current knowledge regarding the interactions between peroxisome and other organelles, i.e., the oil bodies, chloroplast, and mitochondria from the perspective of metabolic and physiological regulation, with reference to various organelle interactions and techniques for estimating organelle interactions occurring in plant cells.
文摘In recent years, stem cells have been a focal point in research designed to evaluate the efficacy of ophthalmologic therapies, specifically those for corneal conditions. The corneal epithelium is one of the few regions of the body that maintains itself using a residual stem cell population within the adjacent limbus. Stem cell movement has additionally captivated the minds of researchers due to its potential application in different body regions. The cornea is a viable model for varying methods to track stem cell migratory patterns, such as lineage tracing and live imaging from the limbus. These developments have the potential to pave the way for future therapies designed to ensure the continuous regeneration of the corneal epithelium following injury via the limbal stem cell niche. This literature review aims to analyze the various methods of imaging used to understand the limbal stem cell niche and possible future directions that might be useful to consider for the better treatment and prevention of disorders of the cornea and corneal epithelium. .
