The mouse is integral to our understanding of hematopoietic biology. Serving as a mammalian model system, the mouse has allowed for the discovery of self-renewing multipotent stem cells, provided functional assays to establish hematopoietic stem cell identity and function, and has become a tool for understanding the differentiation capacity of early hematopoietic progenitors. The advent of gene...

The ability to produce transgenic animals through the introduction of exogenous DNA has existed for many years. However, past methods available to generate transgenic animals, such as pronuclear microinjection or the use of embryonic stem cells, have either been inefficient or not available in all animals, bovine included. More recently somatic cell nuclear transfer has provided a method to cre...

We describe here simple methods for producing transgenic zebrafish reporter lines using BAC clones. The use of BAC clones facilitates creation of useful transgenics as the large amounts of genomic DNA they contain increase the likelihood that reporter gene expression will be properly regulated. Combined with recent advances in live embryo image analysis, this strategy has the potential to great...

Synapses are lost during developmental synapse elimination. Until now, it has been impossible to follow elimination in the entirety of any neuron's branches and synapses. Using transgenic mice in which one or two of a muscle's motoneurons express variants of GFP, Keller-Peck et al. show in this issue of Neuron that elimination occurs asynchronously by local competitive interactions at each syna...

Experiments in vitro suggest that although interleukin 5 (IL5) stimulates the late stages ofeosinophil differentiation, other cytokines are required for the generation of eosinophil progenitor cells . In this study transgenic mice constitutively expressing the IL-5 gene were established using a genomic fragment of the 11,5 gene coupled to the dominant control region from the gene encoding human...

Transgenics and gene targeting by homologous recombination provide an ideal opportunity to delineate immune functions of specific genes. These gene knockout mice are powerful tools to understand complex mechanism of immune system and molecular processes underlying autoimmune diseases and immunodeficiencies. Availability of an increased pool of genetically manipulated mice will provide a basic f...