title: Stable siRNA-mediated silencing of ATM alters the transcriptional profile of HeLa cells.
abstract: The ATM protein, which is mutated in the inherited disease ataxia telangiectasia (AT), is a key regulator of the cells' DNA damage response. AT cells also exhibit constitutive activation of transcriptional regulators such as p53, E2F, AP1, and NFkappaB. Inactivation of ATM may therefore alter the cells' transcriptional profile. ATM expression in HeLa cells was silenced with siRNA expressed from a plasmid based vector, generating a stable cell line, HeLaATM601. HeLaATM601 cells displayed minimal levels of ATM protein and had a 10-fold increase in sensitivity to ionizing radiation. DNA microarray analysis demonstrated that 35 genes were upregulated and five genes were downregulated in HeLaATM601 cells. Genes upregulated in the absence of ATM included interferon-response proteins, cell cycle regulators, integral membrane proteins, and adhesion and extracellular matrix proteins. Using real-time PCR, these genes were also upregulated in cells derived from AT patients. Inactivation of the ATM protein therefore has a significant impact on the transcriptional profile of the cell.
authors.affiliation: Department of Radiation Oncology, JF513, Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney St., Boston, MA 02115, USA.
authors.forename: Shujuan
authors.initials: S
authors.lastname: Chen
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.forename: G Mike
authors.initials: GM
authors.lastname: Makrigiorgos
authors.forename: Brendan D
authors.initials: BD
authors.lastname: Price
mesh_terms: D064007:Ataxia Telangiectasia Mutated Proteins; D018797:Cell Cycle Proteins; D002470:Cell Survival / Q000528:radiation effects; D004268:DNA-Binding Proteins; D005453:Fluorescence; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000502:physiology; D020868:Gene Silencing; D006367:HeLa Cells; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000235:genetics*; D034741:RNA, Small Interfering / Q000502:physiology*; D011839:Radiation, Ionizing; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014162:Transfection; D025521:Tumor Suppressor Proteins
chemical_list: D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D034741:RNA, Small Interfering; D025521:Tumor Suppressor Proteins; C576324:ATM protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; D017346:Protein Serine-Threonine Kinases