The binding of advanced glycation end-products (AGE) to the receptor for AGE (RAGE) is known to deteriorate various cell functions and is implicated in the pathogenesis of diabetic vascular complications. In the present study, we show that the cellular constituents of small vessels, endothelial cells (EC) and pericytes express novel splice variants of RAGE mRNA coding for the isoforms that lack the N-terminal V-type immunoglobulin-like domain (N-truncated) or the C-terminal transmembrane domain (C-truncated), as well as the known full-length mRNA. The ratio of the expression of the three variants was different between EC and pericytes; the content of the C-truncated form was highest in EC, whereas the full-length form was the most abundant in pericytes. Transfection experiments with COS-7 cells demonstrated that those variant mRNAs were translated into proteins as deduced; C-truncated RAGE was efficiently secreted into the culture media, and N-truncated RAGE was located mainly on the plasma membrane. The three isoforms were also detected in primary cultured human EC and pericytes. Further, full-length and C-truncated forms of RAGE bound to an AGE-conjugated column, whereas N-truncated RAGE did not. The AGE induction of extracellular-signal-related kinase phosphorylation and vascular endothelial growth factor in EC and of the growth and cord-like structure formation of EC was abolished completely by C-truncated RAGE, indicating that this endogenous secretory receptor (endogenous secretory RAGE) is cytoprotective against AGE. The results may contribute to our understanding of the molecular basis for the diversity of cellular responses to AGE and for individual variations in the susceptibility to diabetic vascular complications.

These results suggest that the model we have established is useful for not only elucidating the pathogenesis of atopic dermatitis but also for evaluating therapeutic agents.

Posttranslational histone modifications are important for the regulation of many biological phenomena. Here, we show the purification and characterization of nucleosomal histone kinase-1 (NHK-1). NHK-1 has a high affinity for chromatin and phosphorylates a novel site, Thr 119, at the C terminus of H2A. Notably, NHK-1 specifically phosphorylates nucleosomal H2A, but not free H2A in solution. In Drosophila embryos, phosphorylated H2A Thr 119 is found in chromatin, but not in the soluble core histone pool. Immunostaining of NHK-1 revealed that it goes to chromatin during mitosis and is excluded from chromatin during S phase. Consistent with the shuttling of NHK-1 between chromatin and cytoplasm, H2A Thr 119 is phosphorylated during mitosis but not in S phase. These studies reveal that NHK-1-catalyzed phosphorylation of a conserved serine/threonine residue in H2A is a new component of the histone code that might be related to cell cycle progression.[Keywords: Nucleosome; phosphorylation; histone code; transcription; NHK-1] Supplemental material is available at http://genesdev.org.

Various 1,2-isothiazolidine-1,1-dioxide (gamma-sultam) derivatives containing an antioxidant moiety, 2,6-di-tert-butylphenol substituent, were prepared. Some compounds, which have a lower alkyl group at the 2-position of the gamma-sultam skeleton, showed potent inhibitory effects on both cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LO), as well as production of interleukin (IL)-1 in in vitro assays. They also proved to be effective in several animal arthritic models without any ulcerogenic activities. Among these compounds, (E)-(5)-(3,5-di-tert-butyl-4-hydroxybenzylidene)-2-ethyl-1, 2-isothiazolidine-1,1-dioxide (S-2474) was selected as an antiarthritic drug candidate and is now under clinical trials. The structure-activity relationships (SAR) examined and some pharmacological evaluations are described.