Steven N. Fiering
Associate Professor of Microbiology & Immunology, and
Genetics
Research Areas: Genetics, Regulation of Gene Expression
DNA Elements in Regulation of Mammalian Genes During Development
The proper growth and development of a multicellular organism requires appropriate developmental and tissue-specific expression of many genes. Appropriate developmentally-regulated gene expression involves the interplay of protein factors that may or may not be tissue-specific with cis-regulatory DNA elements and related chromatin structure associated with the various genetic loci. We are investigating the DNA elements involved in the regulation of mammalian genes during development by producing specific mutations in the genome of mice and analyzing the associated phenotype. The discovery of genetic homologous recombination in mammalian cells has produced the ability to make specific targeted mutations in the mammalian genome. In association with the ability to use embryonic stem (ES) cells to produce ES cell-derived lines of mice, homologous recombination can be used to make mouse lines with designed mutations and thereby assay the phenotype of known mutations in an otherwise normal animal. This technique is widely used to inactivate (knockout) genes of interest in order to analyze the function of their protein products. We use this approach to investigate the role of cis-regulatory DNA elements, in particular elements associated with the beta-globin locus. In essence we "knockout" putative regulatory elements to assay the role these elements play in regulating the beta-like globin genes. We also utilize a technical system known as recombinase-mediated cassette exchange (RMCE) that permits the reproducible integration of different constructs at specific genomic sites. RMCE permits a detailed analysis of position effect variegation in mammals, including the mechanisms and chromatin structures involved.
Publications
Rosenbauer F, Wagner K, Kutok JL, Iwasaki H, LeBeau M, Okuno Y, Akashi K, Fiering S, and Tenen DG. Acute myeloid leukemia induced by graded reduction of a lineage-specific transcription factor, PU.1. Nature Genetics 36: 624-30, 2004.
Hu X., Bulger M, Roach JN, Eszterhas SK, Olivier E, Bouhassira EE, Groudine M, and Fiering S. Promoters of the murine embryonic $DF-like globin genes Ey and $DFh1 do not compete for interaction with the $DF-globin locus control region. Proc. Natl. Acad. Sci. USA 100:1111-1115, 2003.
Hu, X, M. Bulger, M.A. Bender, J. Fields, M. Groudine, S. Fiering: Deletion of the core region of 5'HS2 of the mouse β-globin locus control region reveals a distinct effect in comparison with human β-globin transgenes. Blood, 107:821-6, 2006