Functional genomic responses to cystic fibrosis transmembrane conductance regulator (CFTR) and CFTR(delta508) in the lung.
Cystic fibrosis (CF), a common lethal pulmonary disorder in Caucasians, is caused by mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR) that disturbs fluid homeostasis and host defense in target organs. The effects of CFTR and delta508-CFTR were assessed in transgenic mice that 1) lack CFTR expression (Cftr-/-); 2) express the human delta508 CFTR (CFTR(delta508)); 3) overexpress the normal human CFTR (CFTR(tg)) in respiratory epithelial cells. Genes were selected from Affymetrix Murine Gene-Chips analysis and subjected to functional classification, k-means clustering, promoter cis-elements/modules searching, literature mining, and pathway exploring. Genomic responses to Cftr-/- were not corrected by expression of CFTR(delta508). Genes regulating host defense, inflammation, fluid and electrolyte transport were similarly altered in Cftr-/- and CFTR(delta508) mice. CFTR(delta508) induced a primary disturbance in expression of genes regulating redox and antioxidant systems. Genomic responses to CFTR(tg) were modest and were not associated with lung pathology. CFTR(tg) and CFTR(delta508) induced genes encoding heat shock proteins and other chaperones but did not activate the endoplasmic reticulum-associated degradation pathway. RNAs encoding proteins that directly interact with CFTR were identified in each of the CFTR mouse models, supporting the hypothesis that CFTR functions within a multiprotein complex whose members interact at the level of protein-protein interactions and gene expression. Promoters of genes influenced by CFTR shared common regulatory elements, suggesting that their co-expression may be mediated by shared regulatory mechanisms. Genes and pathways involved in the response to CFTR may be of interest as modifiers of CF.
Xu
Yan
Y
Division of Pulmonary Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center and The University of Cincinnati College of Medicine, Cincinnati, Ohio 45229-3039, USA. yan.xu@cchmc.org
Liu
Cong
C
Clark
Jean C
JC
Whitsett
Jeffrey A
JA
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D017209:Apoptosis; D016000:Cluster Analysis; D000242:Cyclic AMP / Q000378:metabolism; D003550:Cystic Fibrosis / Q000235:genetics / Q000378:metabolism; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D020869:Gene Expression Profiling / Q000379:methods*; D016678:Genome; D005838:Genotype; D006358:Hot Temperature; D006801:Humans; D007249:Inflammation; D008168:Lung / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D008856:Microscopy, Fluorescence; D008954:Models, Biological; D020411:Oligonucleotide Array Sequence Analysis; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D016133:Polymerase Chain Reaction; D025341:Principal Component Analysis; D011401:Promoter Regions, Genetic; D025941:Protein Interaction Mapping; D012313:RNA / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic
D000975:Antioxidants; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D012313:RNA; D000242:Cyclic AMP