RESUMO
IL-23 is a heterodimeric cytokine composed of a unique p19 subunit and a common p40 subunit is shared with IL-12. IL-23 promotes the inflammatory response by inducing the expansion of CD4(+) cells producing IL-17. The regulation of p19 gene expression has been less studied than that of p40 subunit expression, which in macrophages is well known to be dependent on NF-kappaB. To clarify the role of NF-kappaB in expression of the p19 gene, we analyzed mRNA levels in NF-kappaB-deficient macrophages. As reported to occur in dendritic cells, p19 expression was dramatically reduced in c-rel-deficient macrophages. Moreover, we found that p19 expression was halved in rela-deficient macrophages, but it was enhanced in p52-deficient macrophages. The p19 promoter contains three putative kappaB sites, located at nt -642 to -632 (kappaB-642), nt -513 to -503 (kappaB-513), and nt -105 to -96 (kappaB-105), between the transcription start site and -937 bp upstream in the p19 promoter region. Although EMSA analysis indicated that both kappaB-105 and kappaB-642, but not kappaB-513, bound to NF-kappaB in vitro, luciferase-based reporter assays showed that the most proximal kappaB site, kappaB-105, was uniquely indispensable to the induction of p19 transcription. Chromatin immunoprecipitation demonstrated in vivo association of RelA, c-Rel, and p50 with kappaB-105 of the p19 promoter. These results provide the evidence that the association of RelA and c-Rel with the proximal kappaB site in the p19 promoter is required to induce of p19 expression.
Assuntos
Regulação da Expressão Gênica/fisiologia , Subunidade p19 da Interleucina-23/biossíntese , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-rel/metabolismo , Elementos de Resposta/fisiologia , Fator de Transcrição RelA/metabolismo , Transcrição Gênica/fisiologia , Animais , Sequência de Bases , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Subunidade p40 da Interleucina-12/biossíntese , Subunidade p40 da Interleucina-12/genética , Subunidade p40 da Interleucina-12/imunologia , Interleucina-17/biossíntese , Interleucina-17/genética , Interleucina-17/imunologia , Subunidade p19 da Interleucina-23/genética , Subunidade p19 da Interleucina-23/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , NF-kappa B/genética , NF-kappa B/imunologia , Ligação Proteica , Proteínas Proto-Oncogênicas c-rel/genética , Proteínas Proto-Oncogênicas c-rel/imunologia , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/imunologiaRESUMO
We collected and completely sequenced 28,469 full-length complementary DNA clones from Oryza sativa L. ssp. japonica cv. Nipponbare. Through homology searches of publicly available sequence data, we assigned tentative protein functions to 21,596 clones (75.86%). Mapping of the cDNA clones to genomic DNA revealed that there are 19,000 to 20,500 transcription units in the rice genome. Protein informatics analysis against the InterPro database revealed the existence of proteins presented in rice but not in Arabidopsis. Sixty-four percent of our cDNAs are homologous to Arabidopsis proteins.
