title: Uncovering the basis of ATP hydrolysis activity in purified human p53 protein: a reinvestigation.
abstract: p53 is one of the most well studied tumor suppressor proteins and regarded as the guardian of the genome. The protein mediates cell-cycle arrest, apoptosis in response to myriads of cellular stresses including DNA damage via its transcriptional as well as non-transcriptional roles. ATP binding/hydrolysis by p53 had been implicated in its DNA binding functions. However, till date, no ATP binding/hydrolysis domains have been mapped in p53. In the current study, we have reinvestigated the ATP hydrolysis activity associated with recombinant human p53 protein expressed and purified from E.coli. We confirmed the source of ATPase activity using various deletion constructs of p53 and an In-gel ATPase assay followed by LC-ESI-MS/MS analysis of the activity band. The activity was associated with Hsp70 homologue in E.coli, DnaK, a known interactor of p53. We clarify that wildtype human p53, expressed in E. coli BL21 (DE3) strain, carries no ATPase activity.
authors.affiliation: Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India.
authors.forename: Shalini
authors.initials: S
authors.lastname: Verma
authors.affiliation: Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India.
authors.forename: Basuthkar J
authors.initials: BJ
authors.lastname: Rao
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000737:chemistry / Q000378:metabolism*; D004249:DNA Damage / Q000235:genetics; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D053719:Tandem Mass Spectrometry; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; C063842:dnaK protein, E coli