title: Differential recognition of phosphorylated transactivation domains of p53 by different p300 domains.
abstract: Histone acetyltransferases form crucial links in transducing extrinsic signals to actual initiation of transcription. A multitude of stress signal integrations occur through the interaction of p300 with p53 phosphorylated at different residues of the transactivation domain. How such interactions activate different gene expression programs remains largely unknown. p300 contains at least five domains that are known to interact with p53, but their role in transcription regulation is not known. We measured the binding affinity of various phosphorylated transactivation domains towards several p53 binding domains of p300 by fluorescence anisotropy. The binding affinities of different phosphorylated transactivation domains of p53 towards different domains of p300 vary by several orders of magnitude, indicating that interactions of different post-translationally modified forms of p53 may occur through different domains of p300. Thus, different post-translationally modified p53 fragments may form transcription-initiating complexes of different configurations, leading to the activation of different promoters and pathways.
authors.affiliation: Division of Structural Biology and Bioinformatics, Indian Institute of Chemical Biology, 4 Raja S.C. Mullick Road, Kolkata 700 032, India.
authors.forename: Smarajit
authors.initials: S
authors.lastname: Polley
authors.forename: Soumi
authors.initials: S
authors.lastname: Guha
authors.forename: Neeladri Sekhar
authors.initials: NS
authors.lastname: Roy
authors.forename: Sanchari
authors.initials: S
authors.lastname: Kar
authors.forename: Kazuyasu
authors.initials: K
authors.lastname: Sakaguchi
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Chuman
authors.forename: V
authors.initials: V
authors.lastname: Swaminathan
authors.forename: Tapas
authors.initials: T
authors.lastname: Kundu
authors.forename: Siddhartha
authors.initials: S
authors.lastname: Roy
mesh_terms: D005454:Fluorescence Polarization; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry / Q000378:metabolism*; D050880:p300-CBP Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D000099224:p300-CBP-Associated Factor
chemical_list: D016159:Tumor Suppressor Protein p53; D050880:p300-CBP Transcription Factors; D000099224:p300-CBP-Associated Factor