title: Role of Novel Serine 316 Phosphorylation of the p65 Subunit of NF-κB in Differential Gene Regulation.
abstract: Nuclear factor κB (NF-κB) is a central coordinator in immune and inflammatory responses. Constitutive NF-κB is often found in some types of cancers, contributing to oncogenesis and tumor progression. Therefore, knowing how NF-κB is regulated is important for its therapeutic control. Post-translational modification of the p65 subunit of NF-κB is a well known approach for its regulation. Here, we reported that in response to interleukin 1β, the p65 subunit of NF-κB is phosphorylated on the novel serine 316. Overexpression of S316A (serine 316 → alanine) mutant exhibited significantly reduced ability to activate NF-κB and decreased cell growth as compared with wtp65 (wild type p65). Moreover, conditioned media from cells expressing the S316A-p65 mutant had a considerably lower ability to induce NF-κB than that of wtp65. Our data suggested that phosphorylation of p65 on Ser-316 controls the activity and function of NF-κB. Importantly, we found that phosphorylation at the novel Ser-316 site and other two known phosphorylation sites, Ser-529 and Ser-536, either individually or cooperatively, regulated distinct groups of NF-κB-dependent genes, suggesting the unique role of each individual phosphorylation site on NF-κB-dependent gene regulation. Our novel findings provide an important piece of evidence regarding differential regulation of NF-κB-dependent genes through phosphorylation of different p65 serine residues, thus shedding light on novel mechanisms for the pathway-specific control of NF-κB. This knowledge is key to develop strategies for prevention and treatment of constitutive NF-κB-driven inflammatory diseases and cancers.
authors.affiliation: From the Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, Ohio 44106.
authors.forename: Benlian
authors.initials: B
authors.lastname: Wang
authors.affiliation: Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202.
authors.forename: Han
authors.initials: H
authors.lastname: Wei
authors.affiliation: Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202.
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Prabhu
authors.affiliation: Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, and.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202.
authors.forename: Matthew
authors.initials: M
authors.lastname: Martin
authors.affiliation: Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202.
authors.forename: Antja-Voy
authors.initials: AV
authors.lastname: Hartley
authors.affiliation: Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana 46202, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202, and Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana 46202 lut@iupui.edu.
authors.forename: Tao
authors.initials: T
authors.lastname: Lu
mesh_terms: D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D051379:Mice; D010766:Phosphorylation; D012694:Serine / Q000378:metabolism*; D053719:Tandem Mass Spectrometry; D051996:Transcription Factor RelA / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*
chemical_list: C498144:Rela protein, mouse; D051996:Transcription Factor RelA; D012694:Serine
keywords: NF-κB (NF-κB); mass spectrometry (MS); phosphorylation; post-translational modification (PTM); serine