期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1992
卷号:89
期号:4
页码:1473-1476
DOI:10.1073/pnas.89.4.1473
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Using a DNA probe from the DNA-binding portion of the NF-IL6 gene and an antibody against the DNA-binding domain of NF-IL6, we isolated a gene homologous to NF-IL6 in the DNA-binding and leucine zipper domains. This intronless gene, termed NF-IL6 beta encodes a 269-amino acid protein with a potential leucine zipper structure, and the gene product can bind to the CCAAT homology as well as the viral enhancer core sequence, as in the cases of NF-IL6 and C/EBP. This gene is expressed at an undetectable or a minor level in normal tissues but is induced by lipopolysaccharide or inflammatory cytokines, as in the case of NF-IL6. NF-IL6 beta easily forms a heterodimer with NF-IL6 in vitro and the heterodimeric complex binds to the same DNA sequence as the respective homodimers. When examined by transient luciferase assays, NF-IL6 beta is consistently a stronger transactivator than NF-IL6. Furthermore, NF-IL6 beta shows a synergistic transcriptional effect with NF-IL6. These data suggest that NF-IL6 beta is an important transcriptional activator in addition to NF-IL6 in regulation of the genes involved in the immune and inflammatory responses.