Insulators are elements required for transcriptional fidelity in eukaryotic genomes. Prevailing models suggest that insulators are structural components that divide chromosomes into loop domains to constrain enhancer and silencer action. The goal of our studies is to define mechanisms of insulator action, focusing on the Drosophila gypsy insulator of the gypsy retrovirus. This insulator is bound by the zinc finger protein, Suppressor of Hairy-wing [Su(Hw)], that recruits E(y)2 and two BTB domain proteins, Mod67.2 and CP190. Studies herein will elucidate mechanisms used by these proteins to regulate nuclear organization and gene expression in the Drosophila genome. A multi- faceted approach is proposed to understand the function of Su(Hw) at gypsy and non- gypsy sites in the genome.
Three aims are proposed. First, we will determine the how the gypsy insulator blocks enhancer activated transcription. Second, we will define the role of insulator proteins in chromosome organization. Third, we will elucidate Su(Hw) function at non-gypsy sites in the female germline. These studies will provide new insights into models of insulator function and enhance our understanding of mechanisms involved in genome organization.

Public Health Relevance

Insulators are genomic elements that define domains of independent transcription. Understanding mechanisms of insulator action is critical for improved design of gene therapy vectors, as current approaches face challenges such as inappropriate activation of cellular genes and inadequate long-term expression of therapeutic genes. Such studies will lead to the definition of discrete elements that can be included in the next generation of gene therapy vectors to enhance their effectiveness.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM042539-19
Application #
7933920
Study Section
Molecular Genetics B Study Section (MGB)
Program Officer
Carter, Anthony D
Project Start
1991-04-01
Project End
2012-05-14
Budget Start
2010-09-01
Budget End
2012-05-14
Support Year
19
Fiscal Year
2010
Total Cost
$373,952
Indirect Cost
Name
University of Iowa
Department
Biochemistry
Type
Schools of Medicine
DUNS #
062761671
City
Iowa City
State
IA
Country
United States
Zip Code
52242
Duan, Tingting; Geyer, Pamela K (2018) Spermiogenesis and Male Fertility Require the Function of Suppressor of Hairy-Wing in Somatic Cyst Cells of Drosophila. Genetics 209:757-772
Baxley, Ryan M; Bullard, James D; Klein, Michael W et al. (2017) Deciphering the DNA code for the function of the Drosophila polydactyl zinc finger protein Suppressor of Hairy-wing. Nucleic Acids Res 45:4463-4478
Soshnev, Alexey A; Baxley, Ryan M; Manak, J Robert et al. (2013) The insulator protein Suppressor of Hairy-wing is an essential transcriptional repressor in the Drosophila ovary. Development 140:3613-23
Hohl, Amber M; Thompson, Morgan; Soshnev, Alexey A et al. (2012) Restoration of topoisomerase 2 function by complementation of defective monomers in Drosophila. Genetics 192:843-56
Soshnev, Alexey A; He, Bing; Baxley, Ryan M et al. (2012) Genome-wide studies of the multi-zinc finger Drosophila Suppressor of Hairy-wing protein in the ovary. Nucleic Acids Res 40:5415-31
Soshnev, Alexey A; Ishimoto, Hiroshi; McAllister, Bryant F et al. (2011) A conserved long noncoding RNA affects sleep behavior in Drosophila. Genetics 189:455-68
Geyer, Pamela K; Vitalini, Michael W; Wallrath, Lori L (2011) Nuclear organization: taking a position on gene expression. Curr Opin Cell Biol 23:354-9
Baxley, Ryan M; Soshnev, Alexey A; Koryakov, Dmitry E et al. (2011) The role of the Suppressor of Hairy-wing insulator protein in Drosophila oogenesis. Dev Biol 356:398-410
Kuhn-Parnell, Emily J; Helou, Cecilia; Marion, David J et al. (2008) Investigation of the properties of non-gypsy suppressor of hairy-wing-binding sites. Genetics 179:1263-73
Soshnev, Alexey A; Li, Xingguo; Wehling, Misty D et al. (2008) Context differences reveal insulator and activator functions of a Su(Hw) binding region. PLoS Genet 4:e1000159

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