Escherichia coli possesses three distinct formate dehydrogenase enzymes encoded by the fdnGHI, fdhF, and fdoGHI operons. To examine how two of the formate dehyrogenase operons (fdnGHI and fdhF) are expressed anaerobically in the presence of low, intermediate, and high levels of nitrate, nitrite, and formate, chemostat culture techniques were employed with fdnG-lacZ and fdhF-lacZ reporter fusion...

The E. coli lacZ gene encoding /3-galactosidase has proven to be a useful reporter gene in Dictyostelium (1, 2). We describe a set of three vectors for the rapid construction of promoter ::lacZ fusions. These vectors improve on the previously described vector pDdlac-1 by: (1) the removal of the additional lacZ fragment responsible for instabiity of the polylinker when grown in E. coli; (ii) the...

A 2.4-kb truncated L-plastin promoter was inserted either 5' to the LacZ gene (Ad-Lp-LacZ) or 5' to the cytosine deaminase (CD) gene (Ad-Lp-CD) in a replication-incompetent adenoviral vector backbone. Infectivity and cytotoxicity experiments with the LacZ and CD vectors suggested that the L-plastin promoter-driven transcriptional units were expressed at much higher levels in explants of ovarian...

To determine if endodermal Notch activation and Hes1 expression depends on Dll1 activity, we analyzed NICD expression in wild-type and Dll1lacZ/lacZ embryos and EGFP expression in crosses of Tg(Hes1-EGFP)1Hri and Dll1lacZ/+ mice. NICD expression was reduced in E10.5 Dll1lacZ/lacZ embryos compared with controls (Fig. 2A,B), but appeared to recover, approaching wild-type levels at E11.5 (Fig. 2C,...

Injured podocytes lose differentiation markers. Therefore, the true identity of severely injured podocytes remains unverified. A transgenic mouse model equipped with a podocyte-selective injury induction system was established. After induction of podocyte injury, mice rapidly developed glomerulosclerosis, with downregulation of podocyte marker proteins. Proliferating epithelial cells accumulate...

The alarmone ppGpp is an important signal molecule for the stringent response. Escherichia coli relA encodes a ppGpp synthetase, and although the regulation of RelA protein activity has been studied extensively, the regulation of relA transcription remains unclear. Here, we describe a novel relA promoter, relAP2. According to quantitative measurement of mRNA by primer extension analysis, the pr...

The Escherichia coli sRNA GcvB regulates several genes involved in transport of amino acids and peptides (sstT, oppA, dppA, and cycA). Two regions of GcvB from nt +124 to +161 and from nt +73 to +82 are complementary with essentially the same region of the cycA mRNA. Transcriptional fusions of cycA to lacZ showed the region of cycA mRNA that can pair with either region of GcvB is necessary for ...

Enamel development requires the strictly regulated spatiotemporal expression of genes encoding enamel matrix proteins. The mechanisms orchestrating the initiation and termination of gene transcription at each specific stage of amelogenesis are unknown. In this study, we identify cis- regulatory regions necessary for normal enamelin (Enam) expression. Sequence analysis of the Enam promoter 5'-no...

To investigate in vivo roles of a murine hypothalamic homeobox gene, Bsx, we generated and analyzed two mutant alleles, Bsx(DeltaHD) and Bsx(lacZ). Bsx(DeltaHD) lacks the homeodomain, and Bsx(lacZ) is an insertion of a lacZ reporter gene. Bsx-lacZ expression was detected in the hypothalamus and pineal gland and reiterates Bsx expression. Bsx homozygous mutant mice were born at the expected Mend...