TAp73 protein stability is controlled by histone deacetylase 1 via regulation of Hsp90 chaperone function.
Histone deacetylases (HDACs) play important roles in fundamental cellular processes, and HDAC inhibitors are emerging as promising cancer therapeutics. p73, a member of the p53 family, plays a critical role in tumor suppression and neural development. Interestingly, p73 produces two classes of proteins with opposing functions: the full-length TAp73 and the N-terminally truncated ΔNp73. In the current study, we sought to characterize the potential regulation of p73 by HDACs and found that histone deacetylase 1 (HDAC1) is a key regulator of TAp73 protein stability. Specifically, we showed that HDAC1 inhibition by HDAC inhibitors or by siRNA shortened the half-life of TAp73 protein and subsequently decreased TAp73 expression under normal and DNA damage-induced conditions. Mechanistically, we found that HDAC1 knockdown resulted in hyperacetylation and inactivation of heat shock protein 90, which disrupted the interaction between heat shock protein 90 and TAp73 and thus promoted the proteasomal degradation of TAp73. Functionally, we found that down-regulation of TAp73 was required for the enhanced cell migration mediated by HDAC1 knockdown. Together, we uncover a novel regulation of TAp73 protein stability by HDAC1-heat shock protein 90 chaperone complex, and our data suggest that TAp73 is a critical downstream mediator of HDAC1-regulated cell migration.
Comparative Oncology Laboratory, University of California at Davis, Davis, California 95616.
Jin
J
Zhang
Comparative Oncology Laboratory, University of California at Davis, Davis, California 95616.
Enshun
E
Xu
Comparative Oncology Laboratory, University of California at Davis, Davis, California 95616. Electronic address: xbchen@ucdavis.edu.
Xinbin
X
Chen
D045744:Cell Line, Tumor; D002465:Cell Movement; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D005786:Gene Expression Regulation; D015972:Gene Expression Regulation, Neoplastic; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism*; D056284:Histone Deacetylase 1 / Q000378:metabolism*; D006801:Humans; D018832:Molecular Chaperones / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry* / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism; D020033:Protein Isoforms; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry; D000072160:Tumor Protein p73; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000737:chemistry* / Q000378:metabolism
D004268:DNA-Binding Proteins; D018841:HSP90 Heat-Shock Proteins; D018832:Molecular Chaperones; D009687:Nuclear Proteins; D020033:Protein Isoforms; D011506:Proteins; C495901:TP53 protein, human; C000606460:TP73 protein, human; D000072160:Tumor Protein p73; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; C000606369:delta Np73 protein, human; D046988:Proteasome Endopeptidase Complex; C110550:HDAC1 protein, human; D056284:Histone Deacetylase 1