A chromatin immunoprecipitation screen reveals protein kinase Cbeta as a direct RUNX1 target gene.
RUNX1 (also known as AML1) is a DNA-binding transcription factor that functions as a tumor suppressor and developmental determinant in hematopoietic cells. Target promoters have been identified primarily through the use of differential expression strategies and candidate gene approaches but not biochemical screens. Using a chromatin immunoprecipitation screen, we identified protein kinase Cbeta as a direct RUNX1 target gene and demonstrate that endogenous RUNX1 binds the chromatinized protein kinase Cbeta promoter of U937 cells. A phylogenetically conserved RUNX1-binding site within the PKCbeta promoter binds RUNX1 in electrophoretic mobility shift analyses and confers RUNX1 responsiveness on a heterologous promoter. Changes in RUNX1 activity affect endogenous protein kinase Cbeta expression, and a dominant-negative form of RUNX1 protects U937 cells from apoptotic stimuli previously shown to be dependent on protein kinase Cbeta. This protection can be reversed by the ectopic expression of protein kinase Cbeta. Together these findings demonstrate that protein kinase Cbeta is a direct, downstream target of RUNX1 and links RUNX1 to a myeloid apoptotic pathway.
Hug
Bruce A
BA
Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Pennsylvania Medical Center, Philadelphia, PA 19104, USA.
Ahmed
Nazia
N
Robbins
Jonathan A
JA
Lazar
Mitchell A
MA
D017305:Annexin A1 / Q000494:pharmacology; D017209:Apoptosis; D001483:Base Sequence; D001665:Binding Sites; D015153:Blotting, Western; D002460:Cell Line; D002843:Chromatin / Q000378:metabolism*; D003001:Cloning, Molecular; D050676:Core Binding Factor Alpha 2 Subunit; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005799:Genes, Dominant; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D008969:Molecular Sequence Data; D011233:Precipitin Tests; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011493:Protein Kinase C / Q000378:metabolism*; D064546:Protein Kinase C beta; D011518:Proto-Oncogene Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012689:Sequence Homology, Nucleic Acid; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic; D020298:U937 Cells
D017305:Annexin A1; D002843:Chromatin; D050676:Core Binding Factor Alpha 2 Subunit; D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; C493728:RUNX1 protein, human; D014157:Transcription Factors; D008156:Luciferases; D011493:Protein Kinase C; D064546:Protein Kinase C beta