Genome-wide siRNA screen for mediators of NF-κB activation.

Proc Natl Acad Sci U S A
Authors
Keywords
Abstract

Although canonical NFκB is frequently critical for cell proliferation, survival, or differentiation, NFκB hyperactivation can cause malignant, inflammatory, or autoimmune disorders. Despite intensive study, mammalian NFκB pathway loss-of-function RNAi analyses have been limited to specific protein classes. We therefore undertook a human genome-wide siRNA screen for novel NFκB activation pathway components. Using an Epstein Barr virus latent membrane protein (LMP1) mutant, the transcriptional effects of which are canonical NFκB-dependent, we identified 155 proteins significantly and substantially important for NFκB activation in HEK293 cells. These proteins included many kinases, phosphatases, ubiquitin ligases, and deubiquinating enzymes not previously known to be important for NFκB activation. Relevance to other canonical NFκB pathways was extended by finding that 118 of the 155 LMP1 NF-κB activation pathway components were similarly important for IL-1β-, and 79 for TNFα-mediated NFκB activation in the same cells. MAP3K8, PIM3, and six other enzymes were uniquely relevant to LMP1-mediated NFκB activation. Most novel pathway components functioned upstream of IκB kinase complex (IKK) activation. Robust siRNA knockdown effects were confirmed for all mRNAs or proteins tested. Although multiple ZC3H-family proteins negatively regulate NFκB, ZC3H13 and ZC3H18 were activation pathway components. ZC3H13 was critical for LMP1, TNFα, and IL-1β NFκB-dependent transcription, but not for IKK activation, whereas ZC3H18 was critical for IKK activation. Down-modulators of LMP1 mediated NFκB activation were also identified. These experiments identify multiple targets to inhibit or stimulate LMP1-, IL-1β-, or TNFα-mediated canonical NFκB activation.

Year of Publication
2012
Journal
Proc Natl Acad Sci U S A
Volume
109
Issue
7
Pages
2467-72
Date Published
2012 Feb 14
ISSN
1091-6490
URL
DOI
10.1073/pnas.1120542109
PubMed ID
22308454
PubMed Central ID
PMC3289371
Links
Grant list
R01CA47006 / CA / NCI NIH HHS / United States
U54AI057159 / AI / NIAID NIH HHS / United States
R01043351 / PHS HHS / United States
P30 DK043351 / DK / NIDDK NIH HHS / United States
UL1RR025758 / RR / NCRR NIH HHS / United States
U54 AI057159 / AI / NIAID NIH HHS / United States
K08 CA140780 / CA / NCI NIH HHS / United States
R01 CA047006 / CA / NCI NIH HHS / United States
K08CA140780 / CA / NCI NIH HHS / United States
R01AI062773 / AI / NIAID NIH HHS / United States
P50 HG004233 / HG / NHGRI NIH HHS / United States
R01CA085180 / CA / NCI NIH HHS / United States
R01 AI062773 / AI / NIAID NIH HHS / United States
HGS5P50HG004233 / PHS HHS / United States
UL1 RR025758 / RR / NCRR NIH HHS / United States
T32 CA009031 / CA / NCI NIH HHS / United States
R01 CA085180 / CA / NCI NIH HHS / United States
R0183756 / PHS HHS / United States
5T32CA009031 / CA / NCI NIH HHS / United States