Abstract

The propagation of the eukaryotic genome depends upon the initiation of DNA replication from numerous origins. Origin activity requires the binding and activation of a pre-Replicative Complex (pre-RC). In multi-cellular eukaryotes, however, it is not known how certain regions on chromosomes are selected for pre-RC binding and activation;a DNA consensus has yet to emerge. Moreover, the genomic sites that act as origins, and the time that they initiate during S phase, can change during development, but it is not known what determines this developmental specificity. We have employed a model system based on developmental amplification of Drosophila eggshell (chorion) genes to investigate origin identity and the regulation of genome duplication. Our previous results indicated that nucleosome acetylation regulates the developmental specificity of chorion and other origins in the ovary. We propose to extend this work by investigating the mechanism by which nucleosome modifications influence the activity of origins using genetic and molecular methods. An important aspect of this proposal is that it takes advantage of methods in Drosophila to address the role of chromatin in developmental specificity of origin activity. Our long term goals are to describe the full repertoire of chromatin modifications at origins, to reveal the mechanism by which chromatin alters origin activity, and to discover how these modifications are targeted to specific origins in different cell types in development. This investigation should lead to important new insights into the epigenetic control of genome duplication during development. Lay description: A complete and accurate copy of DNA must be made each cell division. To accomplish this large task, the cell starts copying from numerous """"""""origins"""""""". How certain sites in the genome are chosen to be origins is not understood. This proposal investigates how the structure of chromosomes regulates where DNA replication starts in different cells. The results will provide a deeper understanding for how defects in this process contribute to human cancers, leading to better diagnosis and therapies.

  Funding Agency

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM061290-10
Application #
7688558
Study Section
Molecular Genetics C Study Section (MGC)
Program Officer
Santangelo, George M
Project Start
2000-07-01
Project End
2012-08-31
Budget Start
2009-09-01
Budget End
2012-08-31
Support Year
10
Fiscal Year
2009
Total Cost
$284,115
Indirect Cost

  Institution

Name
Indiana University Bloomington
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
006046700
City
Bloomington
State
IN
Country
United States
Zip Code
47401

  Publications

Paranjape, Neha P; Calvi, Brian R (2016) The Histone Variant H3.3 Is Enriched at Drosophila Amplicon Origins but Does Not Mark Them for Activation. G3 (Bethesda) 6:1661-71
Zhang, B; Rotelli, M; Dixon, M et al. (2015) The function of Drosophila p53 isoforms in apoptosis. Cell Death Differ 22:2058-67
Liu, Jun; Zimmer, Kurt; Rusch, Douglas B et al. (2015) DNA sequence templates adjacent nucleosome and ORC sites at gene amplification origins in Drosophila. Nucleic Acids Res 43:8746-61
Zhang, Bingqing; Mehrotra, Sonam; Ng, Wei Lun et al. (2014) Low levels of p53 protein and chromatin silencing of p53 target genes repress apoptosis in Drosophila endocycling cells. PLoS Genet 10:e1004581
Hassel, Christiane; Zhang, Bingqing; Dixon, Michael et al. (2014) Induction of endocycles represses apoptosis independently of differentiation and predisposes cells to genome instability. Development 141:112-23
Liu, Jun; McConnell, Kristopher; Dixon, Michael et al. (2012) Analysis of model replication origins in Drosophila reveals new aspects of the chromatin landscape and its relationship to origin activity and the prereplicative complex. Mol Biol Cell 23:200-12
McConnell, Kristopher H; Dixon, Michael; Calvi, Brian R (2012) The histone acetyltransferases CBP and Chameau integrate developmental and DNA replication programs in Drosophila ovarian follicle cells. Development 139:3880-90
Maqbool, Shahina B; Mehrotra, Sonam; Kolpakas, Alexis et al. (2010) Dampened activity of E2F1-DP and Myb-MuvB transcription factors in Drosophila endocycling cells. J Cell Sci 123:4095-106
Calvi, B R; Byrnes, B A; Kolpakas, A J (2007) Conservation of epigenetic regulation, ORC binding and developmental timing of DNA replication origins in the genus Drosophila. Genetics 177:1291-301
May, Noah R; Thomer, Marguerite; Murnen, Katherine F et al. (2005) Levels of the origin-binding protein Double parked and its inhibitor Geminin increase in response to replication stress. J Cell Sci 118:4207-17

Showing the most recent 10 out of 11 publications