The expression of gluconeogenic fructose-1,6-bisphosphatase (encoded by the FBP1 gene) depends on the carbon source. Analysis of the FBP1 promoter revealed two upstream activating elements, UAS1FBP1 and UAS2FBP1, which confer carbon source-dependent regulation on a heterologous reporter gene. On glucose media neither element was activated, whereas after transfer to ethanol a 100-fold derepressi...

The aberrant production of nitric oxide (NO) contributes to the pathogenesis of diseases as diverse as cancer and arthritis. Sustained NO production via the inducible enzyme, nitric-oxide synthase 2 (NOS2), requires extracellular arginine uptake. Three closely related cationic amino acid transporter genes (Cat1-3) encode the transporters that mediate most arginine uptake in mammalian cells. Bec...

Maize aminopeptidase is coded by four genes. Amp1 and Amp2 have been localized to chromosome 1. A three-point cross shows the gene order to be Amp2-15%-Amp1-33%-Adh2 (alcohol dehydrogenase). Amp3 and Amp4 assort independently of each other and of chromosome 1 aminopeptidases. Another linkage relationship among the maize genes Amy2 (amylase), Cat1 (catalase), and Amp3 exists, but the chromosome ...

Calcium absorption in intestine and kidney involves transport through the apical membrane, cytoplasm, and basolateral membrane of the epithelial cells. Apical membrane calcium influx channels have recently been described in rabbit (epithelial calcium channel, ECaC) and rat (calcium transport protein, CaT1). We amplified from human duodenum a 446-base partial cDNA probe (ECAC2) having a predicte...

The XC cell line undergoes extensive syncytium formation after infection with ecotropic murine leukemia viruses (MLVs) and is frequently used to titrate these viruses. This cell line is unique in its response to the ecotropic MLV envelope protein (Env) in that it undergoes syncytium formation with cells expressing Env protein containing R peptide (R(+) Env), which is known to suppress the fusog...

The parental cell line (P) of Caco-2 cells and two clones, BBe and TC7, were studied at 11 days postconfluence to test the facilitated diffusion model of vitamin D-mediated intestinal calcium absorption (CaTx). Nuclear vitamin D receptor (nVDR) and calbindin D(9k) (CaBP) were measured by Western blot; 1,25-hydroxyvitamin D(3) 24-hydroxylase (CYP24), CaBP, plasma membrane Ca-ATPase (PMCA), and C...

We describe a Cat-valued nerve of bicategories, which associates to every bicategory a simplicial object in Cat, called the 2-nerve. This becomes the object part of a 2-functor N : NHom → [∆,Cat], where NHom is a 2-category whose objects are bicategories and whose 1-cells are normal homomorphisms of bicategories. The 2-functor N is fully faithful and has a left biadjoint, and we characterize it...