Analysis of Gene Transcription in Cells Lacking DNA-PK Activity

Abstract Bryntesson, F., Regan, J. C., Jeggo, P. A., Taccioli, G. E. and Hubank, M. Analysis of Gene Transcription in Cells Lacking DNA-PK Activity. Radiat. Res. 156, 167–176 (2001). The DNA-dependent protein kinase (DNA-PK), comprised of the Ku70/Ku80 (now known as G22p1/Xrcc5) heterodimer and the catalytic subunit DNA-PKcs (now known as Prkdc), is required for the nonhomologous end joining (NHEJ) pathway of DNA double-strand break repair. The mechanism of action of DNA-PK remains unclear. We have investigated whether DNA-PK regulates gene transcription in vivo after DNA damage using the subtractive hybridization technique of cDNA representational difference analysis (cDNA RDA). Differential transcription, both radiation-dependent and independent, was detected and confirmed in primary mouse embryo fibroblasts from DNA-PKcs–/– and DNA-PKcs+/+ mice. We present evidence that transcription of the extracellular matrix gene laminin alpha 4 (Lama4) is regulated by DNA-PK in a radiation-independent manner. Howev...