细胞技术

Eicosanoids (prostaglandins, leukotrienes and lipoxins) are a family of signaling lipids derived from arachidonic acid that have important roles in physiological and pathological processes. Over the past years, it has been established that successful eicosanoid production is ...

A transgenic mouse, in which the regulatory elements of the stem cell marker, nestin drive green fluorescent protein (ND-GFP), expresses GFP in nascent blood vessels. Red fluorescent protein (RFP)-expressing tumors transplanted to nestin-GFP mice enable specific visualization of ...

Calcium ions play fundamental roles in many cellular processes in virtually all type of cells. The use of Ca2+ sensitive fluorescent indicators has proven to be an indispensable tool for studying the spatio-temporal dynamics of intracellular calcium (i). With the aid of laser scanning conf ...

Planktonic organisms dominate waters in ponds, lakes and oceans. Because of their short life cycles, plankters respond quickly to environmental changes and the variability in their density and composition are more likely to indicate the quality of the water mass in which they are found. Plan ...

We have developed a technique, using a combination of immunofluorescent staining of semi-ultrathin sections of epoxy resin-embedded samples and the corresponding differential interference contrast (DIC) images obtained by light microscopy that provides detailed inform ...

The styryl dye FM1-43 is a powerful tool to track exocytosis, endocytosis and recycling of secretory granules or vesicles. Due to its unique structure, dye molecules reversibly partition into the outer leaflet of surface membrane without permeating due to two cationic charges located in th ...

This chapter is an overview of basic principles of fluorescence microscopy, including a brief history on the invention of this type of microscopy. The chapter highlights important points related to properties of fluorochromes, resolution in fluorescence microscopy, phase contra ...

Activation of the canonical Wnt pathway leads to the transcriptional activation of a particular subset of downstream Wnt target genes. To track this localized cellular output in a living organism, reporter constructs can be designed containing multimerized consensus lymphoid enh ...

Immunodetection of β-catenin accumulation in the nucleus is the most direct and reliable method to determine the intensity and the spatial/temporal patterns of Wnt-dependent signaling activity. Due to the large size of the Xenopus embryo, staining must be done on sections. We present here a s ...

Determining the expression pattern of a gene of interest is critical to understanding when, where, and how it may function during development. This chapter describes methods for determining the localization and expression levels for both mRNA and protein. Some of these methods can be descr ...

Xenopus is an established and powerful model system for the study of Wnt signaling in vertebrates. Above all, the relatively large size of the embryos enables microinjection experiments, which have led to key discoveries not only about the functional role of Wnt signaling in vertebrate embr ...

Wnt signaling plays several important roles in the development of the zebrafish central nervous system (CNS). This chapter outlines both the known and postulated roles of Wnts from the earliest step of neural plate induction to relatively late events such as axon pathfinding and synaptoge ...

The rapid embryonic development and high fecundity of zebrafish contribute to the great advantages of this model for the study of developmental genetics. Transient disruption of the normal function of a gene during development can be achieved by microinjecting mRNA, DNA or short chemica ...

Optically transparent zebrafish embryos provide an excellent vertebrate model system in which to reveal specific mRNA and protein expression patterns during development. Whole-mount preparations can be used to generate three-dimensional color or fluorescent readouts of t ...

Biological cells accomplish their physiological functions using interconnected networks of genes, proteins, and other biomolecules. Most interactions in biological signaling networks, such as bimolecular association or covalent modification, can be modeled in a physic ...

Several strategies based on synthetic oligonucleotides (ON) have been proposed to control gene expression. As for most biomolecules, however, delivery has remained a major roadblock for in vivo applications. Conjugation of steric-block neutral DNA mimics, such as peptide nucleic a ...

The methods for evaluating internalization pathways of cellular CPP-mediated ON delivery utilizing a pre-mRNA splice correction assay and fluorescence-based quantification are described. Examples for characterization of CPP uptake routes, employing various endocyt ...

It is now clear that the major mechanism by which cellular function is switched from one state to another in eukaryotic cells, including the response to cellular stress (1), is via changes in phosphorylation of key proteins. This is usually achieved by modulation of the activity of pre-existing pr ...

Research over the past decade has focused increasingly on the photoreceptor mechanisms that regulate the circadian system in all forms of life. Some of the results to emerge are surprising. For example, the rods and cones within the mammalian eye are not required for the alignment (entrainment) ...

A novel computer model based on a discrete event simulation procedure describes quantitatively the processes underlying the metastatic cascade. Analytical functions describe the size of the primary tumor and the metastases, while a rate function models the intravasation events of ...