Linked Life Data

19675099

Source:http://linkedlifedata.com/resource/pubmed/id/19675099

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2009-12-2
pubmed:abstractText
Upon activation, NF-kappaB translocates into the nucleus and initiates biological events. This NF-kappaB signalling is mainly regulated by the protein kinase IKKbeta. Early in this signalling pathway, IKKbeta is phosphorylated for activation by several factors, such as pro-inflammatory cytokines and the Tax oncoprotein of HTLV-1. In cells infected by HTLV-1, IKKbeta is persistently phosphorylated and conjugated with monoubiquitin due to Tax expression. Although this Tax-induced monoubiquitination appears to be an important regulation system for IKKbeta, how the monoubiquitination occurs is unknown and its role in NF-kappaB signalling is still unclear. Here, we show that an E3-ubiquitin ligase Ro52 interacts weakly with wild-type IKKbeta but strongly with a phosphomimetic mutant IKKbeta to conjugate monoubiquitin in cooperation with an E2-ubiquitin-conjugating enzyme UbcH5B. These results suggest that the Tax-induced phosphorylation of IKKbeta causes an interaction with Ro52 for the subsequent monoubiquitination. NF-kappaB reporter assays have shown that the IKKbeta activity is suppressed by wild-type Ro52, but not by its inactive mutant. In addition, monoubiquitin fusion of IKKbeta reduced its activity for NF-kappaB signalling. We also found that Ro52 dramatically reduces the level of Tax. These results suggest that Ro52 down-regulates Tax-induced NF-kappaB signalling by monoubiquitinating IKKbeta and by reducing the level of Tax.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1756-2651
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
146
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
821-32
pubmed:dateRevised
2011-3-3
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Ro52-mediated monoubiquitination of IKK{beta} down-regulates NF-{kappa}B signalling.
pubmed:affiliation
Department of Cardiology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural