细胞功能测定

The Dictyostelium dicoideum centrosome consists of a box-shaped, layered core structure surrounded by dense nodules embedded in amorphous material, which make up the so-called corona. Thus, it differs markedly from centriole-containing centrosomes in animal cells or the plaque s ...

A major feature in Dictyostelium development is the transition from the unicellular to the multicellular stage, a process brought about by chemotaxis and cell-cell adhesion. Growth-phase cells are weakly cohesive, whereas aggregation-competent cells adhere strongly to each oth ...

Phagocytosis plays a fundamental role in the immune system for the defense against invading microorganisms and the clearing of apoptotic and cancerous cells. The common amoeba Dictyostelium discoideum is a recognized model for professional immune phagocytes and is now commonly us ...

Endocytosis is a process that is essential to the life of all eukaryotic cells. Laboratory strains of Dictyostelium are extremely efficient in the uptake of both particles and fluid. Many different cellular processes feed into the endocytic pathway, and many organelle-associated and cy ...

Fundamental processes in the life of Dictyostelium, such as locomotion, endocytosis, cytokinesis, and morphogenesis, are mediated by the actin cytoskeleton, which is composed of actin, myosins, and numerous actin-binding proteins. An understanding of these processes at the molec ...

Both prokaryote and eukaryote cells can sense and move up chemical concentration gradients (chemotax). As a means of finding food sources during vegetative growth, Dictyostelium discoideum naturally chemotaxes toward chemicals released by bacteria. As part of its developmental ...

Cryopreservation methods, including rapid freezing, freeze-substitution, and low-temperature embedment, lead to superior ultrastructural preservation compared with traditional fixation procedures. This is particularly true for the multicellular stages of Dict ...

Recent years have seen a powerful revival of fluorescence microscopy techniques, both to observe live cells and fixed objects. The limits of sensitivity, simultaneous detection of multiple chromophores, and spatial resolution have all been pushed to the extreme. Therefore, it is essen ...

In the vegetative state, Dictyostelium amoebae are chemotactic toward pterins released by bacteria, whereas during multicellular development, they become chemotactic to endogenously produced cAMP. A variety of assays have been used to visualize and quantify chemotactic move ...

The Dictyostelium discoideum cDNA sequencing project started in 1995, preceding the genome sequencing project. Altogether, 14 cDNA libraries, including full-length ones, were constructed from five different stages of growth and asexual and sexual development, from which near ...

Time-lapse microscopy provides a powerful tool with which to study cell behavior during Dictyostelium development. On a macroscopic level, the overall cell movement patterns that give rise to the complex multicellular structures such as slugs and fruiting bodies can be studied toget ...

The mechanisms that mediate how migratory eukaryotic cells amplify a shallow, extracellular chemoattractant gradient into a steep intracellular gradient of signaling components to guide chemotaxis remains unknown. To unravel these mechanisms, it is essential to quantitat ...

Coordinated cell type differentiation is essential for morphogenesis during Dictyostelium development. The specification of different cell types and the regulation of temporal and spatial patterns of expression of cell type-specific genes are important problems current ...

The advent of the “GFP technology” together with advances in digital imaging and microscopic techniques has revolutionized our view of the living cell. Genetically encoded fluorescent proteins have become widely used as markers in living cells. The application of these fluorescent p ...

Knockouts by homologous recombination are frequently used to investigate the function of genes in Dictyostelium and other organisms. Antisense-mediated gene silencing and RNA interference (RNAi) are convenient alternatives to reduce gene expression to different levels and ...

Dictyostelium discoideum is an exceptionally powerful system by which to study various aspects of modern cell and developmental biology. The completion of the genome sequencing project together with a high-efficiency of targeted gene disruption have enabled researchers to char ...

In the following protocols, broken cells are the starting material of all downstream purifications of functional organelles or intact subcellular membranes. The choice of the breakage method has direct and deep repercussions on the quality of subsequent steps. Breaking vegetative ...

The Dictyostelium discoideum genome has been sequenced, assembled and annotated to a high degree of reliability. The parts-list of proteins and RNA encoded by the six chromosomes can now be accessed and analyzed. One of the initial surprises was the remarkably large number of genes that are shar ...

Dictyostelium discoideum proliferates as solitary amoebae, constitutes multicellular structures called fruiting bodies, and mates to form macrocysts depending on environmental conditions. All of these processes can be easily induced in the laboratory. The amoebae are norm ...

A large number of RNA binding proteins have recently been identified that influence various human genetic disorders. However, the specific function of many of these proteins and what role they may play in a particular disease remains unclear. Identification of the substrate mRNA bound by an R ...