Please use this identifier to cite or link to this item:
|Title:||Identification of PP2A as a novel interactor and regulator of TRIP-Br1|
|Source:||Zang, Z.J., Gunaratnam, L., Cheong, J.K., Hsiao, L.-L., O'Leary, E., Sun, X., Bonventre, J.V., Hsu, S.I.-H., Salto-Tellez, M., Lai, L.Y. (2009). Identification of PP2A as a novel interactor and regulator of TRIP-Br1. Cellular Signalling 21 (1) : 34-42. ScholarBank@NUS Repository. https://doi.org/10.1016/j.cellsig.2008.09.018|
|Abstract:||TRIP-Br proteins are a novel family of transcriptional coregulators involved in E2F-mediated cell cycle progression. Three of the four mammalian members of TRIP-Br family, including TRIP-Br1, are known oncogenes. We now report the identification of the Bα regulatory subunit of serine/threonine protein phosphatase 2A (PP2A) as a novel TRIP-Br1 interactor, based on an affinity binding assay coupled with mass spectrometry. A GST-TRIP-Br1 fusion protein associates with catalytically active PP2A-ABαC holoenzyme in vitro. Coimmunoprecipitation confirms this association in vivo. Immunofluorescence staining with a monoclonal antibody against TRIP-Br1 reveals that endogenous TRIP-Br1 and PP2A-Bα colocalize mainly in the cytoplasm. Consistently, immunoprecipitation followed by immunodetection with anti-phosphoserine antibody suggest that TRIP-Br1 exists in a serine-phosphorylated form. Inhibition of PP2A activity by okadaic acid or transcriptional silencing of the PP2A catalytic subunit by small interfering RNA results in downregulation of total TRIP-Br1 protein levels but upregulation of serine-phosphorylated TRIP-Br1. Overexpression of PP2A catalytic subunit increases TRIP-Br1 protein levels and TRIP-Br1 co-activated E2F1/DP1 transcription. Our data support a model in which association between PP2A-ABαC holoenzyme and TRIP-Br1 in vivo in mammalian cells represents a novel mechanism for regulating the level of TRIP-Br1 protooncoprotein. © 2008 Elsevier Inc. All rights reserved.|
|Source Title:||Cellular Signalling|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Dec 6, 2017
WEB OF SCIENCETM
checked on Nov 17, 2017
checked on Dec 10, 2017
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.