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：2009
卷号：106
期号：24
页码：9779-9784
DOI：10.1073/pnas.0812022106
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The Drosophila NF-{kappa}B transcription factor Relish is an essential regulator of antimicrobial peptide gene induction after Gram-negative bacterial infection. Relish is a bipartite NF-{kappa}B precursor protein, with an N-terminal Rel homology domain and a C-terminal I{kappa}B-like domain, similar to mammalian p100 and p105. Unlike these mammalian homologs, Relish is endoproteolytically cleaved after infection, allowing the N-terminal NF-{kappa}B module to translocate to the nucleus. Signal-dependent activation of Relish, including cleavage, requires both the Drosophila I{kappa}B kinase (IKK) and death-related ced-3/Nedd2-like protein (DREDD), the Drosophila caspase-8 like protease. In this report, we show that the IKK complex controls Relish by direct phosphorylation on serines 528 and 529. Surprisingly, these phosphorylation sites are not required for Relish cleavage, nuclear translocation, or DNA binding. Instead they are critical for recruitment of RNA polymerase II and antimicrobial peptide gene induction, whereas IKK functions noncatalytically to support Dredd-mediated cleavage of Relish.
