Inosine (I) at position 34 (wobble position) of tRNA is formed by the hydrolytic deamination of a genomically encoded adenosine (A). The enzyme catalyzing this reaction, termed tRNA A:34 deaminase, is the heterodimeric Tad2p/ADAT2.Tad3p/ADAT3 complex in eukaryotes. In budding yeast, deletion of each subunit is lethal, indicating that the wobble inosine tRNA modification is essential for viabili...

Regulatory T (T reg) cell deficiency causes lethal, CD4+ T cell-driven autoimmune diseases. Stem cell transplantation is used to treat these diseases, but this procedure is limited by the availability of a suitable donor. The intestinal microbiota drives host immune homeostasis by regulating the differentiation and expansion of T reg, Th1, and Th2 cells. It is currently unclear if T reg cell de...

The resistance of a Novikoff hepatoma cell line (Ni -Si I FdUrd) to 5-fluorouracil (FUra) was reversed by the inclusion of inosine in the culture medium. As the concentration of inosine in the medium was increased, there was a marked increasein the uptakeof [14C]FUra nd conversionto nucleo tides with a corresponding increase in the incorporation into RNA. While FUra alone had no effect on this ...

Adenosine, formed from AMP and metabolized to inosine, modulates renal sympathetic neurotransmission. The present study had two goals: 1) to develop ultrasensitive and specific mass spectrometry-based assays for cAMP, AMP, adenosine, inosine, and, for comparison, guanosine using state-of-the-art tandem liquid chromatography-mass spectrometry (LC-MS-MS); and 2) to quantify the effects of renal s...

Human intestinal epithelial cell monolayers (Caco-2) subjected to hypoxia and reoxygenation release soluble factors into the apical medium that activate the virulence of the opportunistic pathogen Pseudomonas aeruginosa to express the potent barrier-dysregulating protein PA-I lectin/adhesin. In this study, we defined the role of hypoxia-inducible factor (HIF)-1alpha in this response. We tested ...

Introduction The pharmaceutical industry, in an attempt to develop drugs for immunosuppression and to control cell proliferation, has turned its attention to inosine 5’monophosphate dehydrogenase (IMPDH). IMPDH, a homotetramer composed predominantly of a (β/α)8 barrel, is the enzyme which catalyzes the conversion of inosine monophosphate (IMP) to xanthosine monophosphate (XMP) in the de novo sy...

Substitution of inosine for granosine in the nucleic acid fragments synthesized for the sequencing of RNA effectively prevents the formation of secondary structures during electrophoretic analysis. Consequently, the mobility of each fragment in the sequencing gel is a strict function of its molecular weight. Inosine substitution should markedly improve the resolution that can be obtained in the...

The yeast YLR209c (PNP1) gene encodes a protein highly similar to purine nucleoside phosphorylases. This protein specifically metabolized inosine and guanosine. Disruption of PNP1 led to inosine and guanosine excretion in the medium, thus showing that PNP1 plays an important role in the metabolism of these purine nucleosides in vivo.