We have replaced part of the mouse homeogene Otx2 coding region with the E. coli lacZ coding sequence, thus creating a null allele of Otx2. By 9.5 dpc, homozygous mutant embryos are characterized by the absence of forebrain and midbrain regions. From the early to midstreak stages, endomesodermal cells expressing lacZ fail to be properly localized anteriorly. In the ectodermal layer, lacZ transc...

The vertebrate caudal proteins, being upstream regulators of the Hox genes, play a role in establishment of the body plan. We describe analysis of two orthologous caudal genes (chick cdx-A and mouse cdx-1) by use of lacZ reporters expressed in transgenic mouse embryos. The expression patterns show many similarities to the expression of endogenous mouse cdx-1. At 8.7 days, cdx/lacZ activity with...

Photoacoustic molecular imaging, combined with the reporter-gene technique, can provide a valuable tool for cancer research. The expression of the lacZ reporter gene can be imaged using photoacoustic imaging following the injection of X-gal, a colorimetric assay for the lacZ-encoded enzyme β-galactosidase. Dual-wavelength photoacoustic microscopy was used to non-invasively image the detailed mo...

We have developed a positive screen for cloning PCR products based on translational activation of lacZ. A vector with a translationally deficient lacZ alpha gene has been made by deletion of the Shine-Dalgarno sequence and initiation codon. The Shine-Dalgarno sequence and initiation codon are incorporated into one of the PCR primers to allow complementation by the PCR product of the inactive la...

Human Platt neuroblastoma cells were transfected with the marker gene, bacterial lacZ, to track cells at the earliest stages after ectopic injection at two different sites in athymic nude mice. Three clones (LZPt-1,-2 and -3) of differing morphologies were analysed. All clones yielded large primary tumours subcutaneously or intradermally with similar latency. While LZPt-2 and -3 clones generate...

We examined the role of Notch signaling on the generation of neurons and glia from neural stem cells by using neurospheres that are clonally derived from neural stem cells. Neurospheres prepared from Dll1(lacZ/lacZ) mutant embryos segregate more neurons at the expense of both oligodendrocytes and astrocytes. This mutant phenotype could be rescued when Dll1(lacZ/lacZ) spheres were grown and/or d...

Results on the localization of erythropoietin (Epo) synthesis in renal cells have been contradictory, implicating either interstitial or tubular cells. We fused the lacZ gene to a 7-kb DNA fragment of the mouse Epo gene encompassing a portion of the first intron, the first exon, and a 6-kb sequence of the 5'-flanking region. Transgenic mice carrying this construct show a low level of specific e...

We have developed a large-scale, expression-based gene trap strategy to perform genome-wide functional analysis of the murine hematopoietic and vascular systems. Using two different gene trap vectors, we have isolated embryonic stem (ES) cell clones containing lacZ reporter gene insertions in genes expressed in blood island and vascular cells, muscle, stromal cells, and unknown cell types. Of 7...

The transposition of P elements in Drosophila melanogaster is regulated by products encoded by the P elements themselves. The molecular mechanisms of this regulation are complex and still unclear. We have assayed in vivo the effects of P regulatory products on the P promoter itself by using P-lacZ fusion genes. We have found that all the P-lacZ insertions are repressed in a P background. This r...

objective(s):diabetic nephropathy is an important long-term complication of diabetes mellitus which appears to be partially mediated by an increase in secretion of transforming growth factor-β (tgf-β). fibromodulin, the small leucine-rich proteoglycan, has been proposed to be the potent tgfβ1 modulator. in this study, the therapeutic effects of recombinant adenoviral vectors expressing fibromod...