细胞技术

The use of genetically modified retroviruses as agents for gene transfer has provided developmental biology with some of its most elegant and compelling research stories of the last few years. The growing recognition of the utility of retrovirally derived constructs is perhaps unsurp ...

In female mammals, one of the two X chromosomes in each and every embryonic cell is randomly inactivated during embryogenesis, leaving only one active X chromosome per cell and thereby maintaining dosage parity with males (1). This natural phenomenon, known as X inactivation or lyonization, p ...

The ideal cell lineage marker is one that can be visualized in living tissues without perturbing development. Exogenously applied dyes are very useful, but in many instances there would be advantages to an endogenously expressed marker. Green fluorescent protein (GFP) appears to have the p ...

The development of fluorescent calcium (Ca2+) indicators has been a very powerful tool for looking at the role of this second messenger in signal transduction. The ability to load these indicators into cells in a nondisruptive manner allow for the visualization of intracellular-free Ca2+ i ...

The chick embryo provides an excellent model system for studying the development of higher vertebrates wherein growth accompanies morphogenesis. (Note: virtually all information given here for the chick embryo is applicable to the quail embryo, and much of it is applicable to embryos of o ...

Current understanding of organ-level vertebrate heart development has been gained primarily from studies of avian and amphibian heart development from whole-mount culture studies and subsequent dissections and serial sections of the heart during different stages of develop ...

Extensive genetic information and transgenic techniques available in the mouse have led to its wide use in studies of mammalian development and models of human disease. A basic limitation of analyzing dynamic developmental processes in mouse embryos is their inaccessibility, becau ...

Optical coherence tomography (OCT) is an attractive imaging technique for developmental biology because it permits the imaging of tissue microstructure in situ, yielding micron-scale image resolution without the need for excision of a specimen and tissue processing. OCT enables r ...

Analyzing phenotypic effects in embryos produced with directed gene manipulation is a major challenge for developmental biologists who are trained in molecular techniques but who are not well-versed in embryology. Analysis techniques that preserve the three-dimensional (3-D) ...

For topographical (surface) analysis of developing embryos, investigators typically rely on scanning electron microscopy (SEM) to provide the surface detail not attainable with light microscopy. Although it provides beautiful surface detail, SEM is an expensive and time-cons ...

In our efforts to use confocal laser scanning microscopy for study of organogenesisstage rodent embryos, we have developed fixation and clearing methods to allow optical sectioning through embryos with thickness approaching 1 mm (z-axis). We have combined fixation and clearing meth ...

A major conceptual breakthrough has occurred in the field of developmental morphogenesis in the past decade. It is now clear that molecular mechanisms at the external cell surface and within the surrounding extracellular matrix are fundamental to embryogenesis. Adhesion receptor ...

The use of the confocal microscope to study living Xenopus eggs affords the opportunity to obtain four-dimensional (4-D) data (three-dimensional data over time) throughout early development of these large cells. Microscopy of living cells often reveals important information about ...

The development of a complex multicellular organism from a single-celled zygote requires that the protein structures encoded in the DNA of the organism’s genome be expressed in specified cells at specified levels, contingent on specific signals generated at specific stages of develo ...

Development of tissues and organs relies on the constant interplay of intracellular events and molecules in the microenvironment of the cells. Dynamics of patterning of molecules in a spatiotemporal manner become important in understanding any developing system. Immunohistoc ...

Cardiovascular anomalies are the most common birth defects in man, accounting for 0.5–1% of live births. They are typically classified according to the affected segment of the heart. The complexity of an anomaly, its relationship to other cardiac structures, and its physiologic consequen ...

The axial skeleton represents one product of the metameric segregation of the mesoderm in the developing embryo. The mechanisms underlying this pattern formation remain poorly understood. Genetic alterations, either resulting from spontaneous mutation or as a result of xenobio ...

In this overview, we examine approaches to the embryological development of the craniofacial region of avian and rodent embryos. By craniofacial region we mean: externally, the face and head, excluding the caudal pharyngeal arches; internally, the brain, skull, jaws, and facial skeleton, ...

The process of gastrulation occurs during the early embryogenesis of vertebrates, immediately following the phase of cleavage and when the embryo is at the blastula stage. Gastrulation results in the formation of the primitive gut or archenteron. With the initial formation of the archen ...

In situ hybridization of nucleotide sequence to Drosophila melanogaster interphase polytene chromosomes was initially developed by Pardue, who has published an extensive account of Drosophila polytene chromosomes and hybridization to these chromosomes (1). The procedure, ...