Engagement of Components of DNA-Break Repair Complex and NF[kappa]B in Hsp70A1A Transcription Upregulation by Heat Shock

• Published in: PloS one 2017-01, Vol.12 (1), p.e0168165
• Main Authors: Hazra, Joyita, Mukherjee, Pooja, Ali, Asif, Poddar, Soumita, Pal, Mahadeb
• Format: Article
• Language: English
• Subjects: Analysis; DNA repair; Genetic aspects; Heat shock proteins; Transcription (Genetics)
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0168165

An involvement of components of DNA-break repair (DBR) complex including DNA-dependent protein kinase (DNA-PK) and poly-ADP-ribose polymerase 1 (PARP-1) in transcription regulation in response to distinct cellular signalling has been revealed by different laboratories. Here, we explored the involvement of DNA-PK and PARP-1 in the heat shock induced transcription of Hsp70A1A. We find that inhibition of both the catalytic subunit of DNA-PK (DNA-PKc), and Ku70, a regulatory subunit of DNA-PK holo-enzyme compromises transcription of Hsp70A1A under heat shock treatment. In immunoprecipitation based experiments we find that Ku70 or DNA-PK holoenzyme associates with NF[kappa]B. This NF[kappa]B associated complex also carries PARP-1. Downregulation of both NF[kappa]B and PARP-1 compromises Hsp70A1A transcription induced by heat shock treatment. Alteration of three bases by site directed mutagenesis within the consensus [kappa]B sequence motif identified on the promoter affected inducibility of Hsp70A1A transcription by heat shock treatment. These results suggest that NF[kappa]B engaged with the [kappa]B motif on the promoter cooperates in Hsp70A1A activation under heat shock in human cells as part of a DBR complex including DNA-PK and PARP-1.