Linked Life Data

18842582

Source:http://linkedlifedata.com/resource/pubmed/id/18842582

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
51
pubmed:dateCreated
2008-12-16
pubmed:abstractText
Pre-mRNA splicing entails reversible phosphorylation of spliceosomal proteins. Recent work has revealed essential roles for Ser/Thr phosphatases, such as protein phosphatase-1 (PP1), in splicing, but how these phosphatases are regulated is largely unknown. We show that nuclear inhibitor of PP1 (NIPP1), a major PP1 interactor in the vertebrate nucleus, recruits PP1 to Sap155 (spliceosome-associated protein 155), an essential component of U2 small nuclear ribonucleoprotein particles, and promotes Sap155 dephosphorylation. C-terminally truncated NIPP1 (NIPP1-DeltaC) formed a hyper-active holoenzyme with PP1, rendering PP1 minimally phosphorylated on an inhibitory site. Forced expression of NIPP1-WT and -DeltaC resulted in slight and severe decreases in Sap155 hyperphosphorylation, respectively, and the latter was accompanied with inhibition of splicing. PP1 overexpression produced similar effects, whereas small interfering RNA-mediated NIPP1 knockdown enhanced Sap155 hyperphosphorylation upon okadaic acid treatment. NIPP1 did not inhibit but rather stimulated Sap155 dephosphorylation by PP1 in vitro through facilitating Sap155/PP1 interaction. Further analysis revealed that NIPP1 specifically recognizes hyperphosphorylated Sap155 thorough its Forkhead-associated domain and dissociates from Sap155 after dephosphorylation by associated PP1. Thus NIPP1 works as a molecular sensor for PP1 to recognize phosphorylated Sap155.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
283
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
35805-14
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Nuclear inhibitor of protein phosphatase-1 (NIPP1) directs protein phosphatase-1 (PP1) to dephosphorylate the U2 small nuclear ribonucleoprotein particle (snRNP) component, spliceosome-associated protein 155 (Sap155).
pubmed:affiliation
Division of Cancer Chemotherapy, Miyagi Cancer Center Research Institute, Natori 981-1293, Japan. tanuma-no872@pref.miyagi.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't