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PubMed · 11076933

p300 does not require its acetylase activity to stimulate p73 function.

X Zeng·H Lee·Q Zhang·H Lu
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Abstract

We previously reported that p73, like p53, utilizes p300 or cAMP-response element-binding protein-binding protein as its coactivator. Here, we extended this work by further examining whether the intrinsic acetylase activity of p300 is necessary for stimulating p73 function. Although p300 acetylated the C-terminal fragment of p73 (amino acids 311-636) in vitro, it was unable to efficiently acetylate the full-length p73. Consistently, p300 did not acetylate p73 in vivo when both the proteins were overexpressed in cells. Also, an acetylase-defective mutant p300 named p300AT2 was able to elevate p73-dependent transcription in cells. p300 associated with p73 when forming DNA-protein complexes and stabilized p73 proteins. These results demonstrate that p300 does not need its acetylase activity to be a coactivator of p73.

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AcetylationAcetyltransferasesCarcinoma, Small CellCell Cycle ProteinsDNADNA-Binding ProteinsGene Expression RegulationGenes, Tumor SuppressorHistone AcetyltransferasesHumansLung NeoplasmsMutationNuclear ProteinsPeptide FragmentsProtein BindingRecombinant ProteinsTranscription FactorsTranscription, GeneticTumor Cells, CulturedTumor Protein p73Tumor Suppressor Proteinsp300-CBP Transcription Factorsp300-CBP-Associated FactorJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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X Zeng, H Lee, Q Zhang, H Lu. 2001-01-05. p300 does not require its acetylase activity to stimulate p73 function.. https://doi.org/10.1074/jbc.c000722200

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