title: Peptide nucleic acid (PNA) binding-mediated induction of human gamma-globin gene expression.
abstract: Peptide nucleic acids (PNAs) can bind to homopurine/homopyrimidine sequences of double-stranded DNA targets in a sequence-specific manner and form [PNA]2/DNA triplexes with single-stranded DNA D-loop structures at the PNA binding sites. These D-loop structures have been found to have a capacity to initiate transcription in vitro. If this strategy can be used to induce transcription of endogenous genes, it may provide a novel approach for gene therapy of many human diseases. Human [beta] globin disorders such as sickle cell anemia and beta-thalassemia are very common genetic diseases that are caused by mutations in the beta-globin gene. When gamma-globin genes are highly expressed in sickle cell patients, the presence of high levels of fetal hemoglobin (HbF, alpha2gamma2) can compensate for the defective beta-globin gene product and such patients have much improved symptoms or are free of disease. However, the gamma-globin genes are developmentally regulated and normally expressed at very low levels (>1%) in adult blood cells. We have investigated the possibility of inducing gamma-globin gene expression with PNAs. Using PNAs designed to bind to the 5' flanking region of the gamma-globin gene, induction of expression of a reporter gene construct was demonstrated both in vitro and in vivo. More importantly, PNA-mediated induction of endogenous gamma-globin gene expression was also demonstrated in K562 human erythroleukemia cells. This result suggests that induction of gamma-globin gene expression with PNAs might provide a new approach for the treatment of sickle cell disease. PNA-induced gene expression strategy also may have implications in gene therapy of other diseases such as genetic diseases, cancer and infectious diseases.
authors.affiliation: Department of Structural and Cellular Biology, University of South Alabama College of Medicine, MSB 2042, Mobile, AL 36688-0002, USA. gwang@jaguar1.usouthal.edu
authors.forename: G
authors.initials: G
authors.lastname: Wang
authors.forename: X
authors.initials: X
authors.lastname: Xu
authors.forename: B
authors.initials: B
authors.lastname: Pace
authors.forename: D A
authors.initials: DA
authors.lastname: Dean
authors.forename: P M
authors.initials: PM
authors.lastname: Glazer
authors.forename: P
authors.initials: P
authors.lastname: Chan
authors.forename: S R
authors.initials: SR
authors.lastname: Goodman
authors.forename: I
authors.initials: I
authors.lastname: Shokolenko
mesh_terms: D000755:Anemia, Sickle Cell / Q000097:blood / Q000235:genetics; D001483:Base Sequence; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D005914:Globins / Q000096:biosynthesis / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D020135:Peptide Nucleic Acids / Q000235:genetics*; D014158:Transcription, Genetic; D017086:beta-Thalassemia / Q000097:blood / Q000235:genetics
chemical_list: D020135:Peptide Nucleic Acids; D005914:Globins