Anti-S. cerevisiae NOP2 Monoclonal antibody, Clone 34I3

New ligands, 2-(4-methoxyphenyl)imidazo [4,5-f][1,10] phenanthroline (MOP) and 2-(4-dimethylaminophenyl)imidazo[4,5-f] [1,10]phenanthroline (DMNP) and their (bpy)(2)Ru2+ complexes (bpy=2,2'-bipyridine), have been synthesized. Single crystal X-ray diffraction reveals that MOP is a planar molecule. The binding of the above two complexes, Ru(bpy)(2)NOP2+ and (NOP=2-(4-nitrophenyl) imidazo [4,5-f] [ 1,10] phenanthroline) to calf thymus DNA is investigated using various photophysical methods. Considerable absorption, hypo- and bathochromicity, as well as enantiomeric selectivity demonstrate that the complexes bind to DNA through intercalation of MOP, DMNP or NOP into the base pairs. The absorption change, regarding the DMNP or NOP localized transition, provides a unique 'direct' criterion. Steady-state emission enhancement, reduced accessibility to ferrocyanide quencher, and an excited-state Lifetime increase are also observed for Ru(bpy)(2)MOP2+ and Ru(bpy)(2)DMNP2+ once bound to DNA. The monoexponential emission-decay profiles infer that the perpendicular intercalation might be the sole binding mode. Owing to a relatively low sensitivity to collision-quenching by neighboring molecules, the emission change of Ru(bpy)(2)DMNP2+ is lower than that of Ru(bpy)(2)MOP2+.No emission is observed for Ru(bpy)(2)NOP2+ due to intramolecular electron transfer caused by -NO2, which is unaffected by DNA. (C) 1998 Elsevier Science S.A. All rights reserved.

Rationale: Vascular endothelial inflammation, including the expression of intercellular adhesion molecule 1 (ICAM-1), is a key event in vascular diseases. However, the mechanisms underlying the regulation of ICAM-1 are largely unknown. Objective: To investigate the mechanisms on the regulation of ICAM-1 by NOP2/Sun domain family, member 2 (NSun2)-mediated mRNA methylation and the impact of NSun2-ICAM-1 regulatory process in vascular inflammation and allograft arteriosclerosis. Methods and Results: By using in vitro, in cells, and in vivo methylation assays, we showed that the tRNA methyltransferase NSun2 methylated the ICAM-1 mRNA. Methylation by NSun2 promoted the translation of ICAM-1, thereby increasing the adhesion of leukocytes to endothelial cells. Tumor necrosis factor- or homocysteine activated the methyltransferase activity of NSun2 by repressing the phosphorylation of NSun2 by Aurora-B. The levels of ICAM-1 induction and of leukocyte adhesion to vascular endothelium observed with homocysteine treatment in wild-type rats were markedly decreased in NSun2(-/-) rats. In a rat model of aortic allograft, the lack of donor NSun2 impaired the formation of allograft arteriosclerosis. Conclusions: NSun2 upregulates the expression of ICAM-1 by methylating ICAM-1 mRNA. This regulatory process impacts on vascular inflammation and allograft arteriosclerosis.