Gene expression profile analysis of 4-phenylbutyrate treatment of IB3-1 bronchial epithelial cell line demonstrates a major influence on heat-shock proteins

• Published in: Physiological genomics Vol. 16; no. 2; pp. 204 - 211
• Main Authors: Wright, Jerry M, Zeitlin, Pamela L, Cebotaru, Liudmila, Guggino, Sandra E, Guggino, William B
• Format: Journal Article
• Language: English
• Published: United States Am Physiological Soc 15.01.2004
• Subjects: 4-phenylbutryate; Animals; Bronchi - cytology; Bronchi - metabolism; Cell Line; CFTR protein; Cystic Fibrosis Transmembrane Conductance Regulator - metabolism; Endoplasmic Reticulum - metabolism; Epithelial Cells - drug effects; Epithelial Cells - metabolism; Gene Expression Profiling; Gene Expression Regulation; Heat-Shock Proteins - biosynthesis; Heat-Shock Proteins - genetics; Kinetics; Mice; Oligonucleotide Array Sequence Analysis; Phenylbutyrates - pharmacology; Protein Folding; Protein Transport; Respiratory Mucosa - metabolism
• ISSN: 1094-8341; 1531-2267
• DOI: 10.1152/physiolgenomics.00160.2003

1 Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287 2 Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287 3 Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287 Most individuals with cystic fibrosis (CF) carry one or two mutations that result in a maturation defect of the full-length CFTR protein. The F508 mutation results in a mutant protein that is degraded by the proteosome instead of progressing to the apical membrane where it functions as a cAMP-regulated chloride channel. 4-Phenylbutyrate (PBA) modulates heat-shock protein expression and promotes trafficking of F508, thus permitting maturation and membrane insertion. The goal of this study was to gain insight into the genetic mechanism of PBA action through a large-scale analysis of gene expression. The Affymetrix genome-spanning U133 microarray set was used to compare mRNA expression levels in untreated IB3-1 cell line cultures with cultures treated with 1 mM PBA for 12 and 24 h. The most notable changes in mRNA levels were transient elevations in heat-shock proteins. The majority of genes downregulated throughout the application period were functionally associated with control of gene expression. Another set of genes increased in expression starting at 24 h, suggesting these are downstream effects of altered gene expression initiated by PBA. More than one-third of the genes in this late expressing set were identified as having potential significance in understanding the pathology of CF. Our results demonstrate the usefulness of gene expression profile analysis in understanding the consequences of PBA treatment and provide insights in how this drug exerts its effect on the trafficking of CFTR. microarray; chaperones; cystic fibrosis; RNA