The broad, long-term objective is to understand the significance and molecular mechanism of the epigenetic phenomenon of genetic imprinting in mammalian development. Genetic imprinting in the mouse apparently effects differential expression of certain genes according to parental origin, and the normal level of expression of at least some of these genes is critical for normal embryogenesis. It is being realized that genetic imprinting underlies the etiology of a number of important inherited human syndromes, as well as cancers, and there is evidence that homologous genes may be imprinted in human and mouse.
The specific aims are to (i) determine the role of the distal region of chromosome 7 in androgenetic and parthenogenetic inviability. The importance of possible aberrant expression of the distal 7 gene, H19, will also be addressed, (ii) define in detail the distribution of androgenetic (two paternal genomes) and parthenogenetic (two maternal genomes) cells in chimeras in relation to their differentiative and proliferative capacity, and to the pathology they induce. This will provide basic information which might lead to the elucidation of the aberrant gene expression that must exist, (iii) test whether imprinted genes might act as developmental switch genes in hematopoiesis, and (iv) identify and determine the function of a significant number of developmentally important imprinted genes. The experimental design will make use of unique embryonic stem (ES) cell lines in which patterns of genetic imprinting are abnormal. These include cell lines with extreme maternal/paternal genetic imbalance, i.e. androgenetic and parthenogenetic, and those with partial imbalance, i.e. carrying paternal or maternal duplication of the distal region of chromosome 7. These cells are presumed to possess differential or mutually exclusive expression of certain genes. The methods to be employed in accordance with the specific aims will be (i) derivation and analysis of the developmental capacity in chimeras of ES cells with paternal and maternal duplication of distal 7. The role of H19 will be examined by manipulating its expression in androgenetic and parthenogenetic ES cells, then determining the fate of these altered cells in chimeras, (ii) production of chimeras using androgenetic and parthenogenetic ES cells or cleavage-stage eggs carrying a cell-- autonomous marker that can be visualized by DNA-DNA in situ hybridization in histological sections, (iii) analysis of the reconstitution of hematopoietic lineages by androgenetic and parthenogenetic hematopoietic stem cells, and (iv) differential (+/-) screening of androgenetic and parthenogenetic cDNA libraries employing subtraction technology.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM048103-06
Application #
2900788
Study Section
Human Embryology and Development Subcommittee 1 (HED)
Project Start
1992-08-01
Project End
2001-03-31
Budget Start
1999-04-01
Budget End
2000-03-31
Support Year
6
Fiscal Year
1999
Total Cost
Indirect Cost
Name
City of Hope/Beckman Research Institute
Department
Type
DUNS #
City
Duarte
State
CA
Country
United States
Zip Code
91010
Han, Li; Szabó, Piroska E; Mann, Jeffrey R (2010) Postnatal survival of mice with maternal duplication of distal chromosome 7 induced by a Igf2/H19 imprinting control region lacking insulator function. PLoS Genet 6:e1000803
Nucci, Nathaniel V; Scott, J Nathan; Vanderkooi, Jane M (2008) Coupling of complex aromatic ring vibrations to solvent through hydrogen bonds: effect of varied on-ring and off-ring hydrogen-bonding substitutions. J Phys Chem B 112:4022-35
Tang, Shih-Huey E; Silva, Francisco J; Tsark, Walter M K et al. (2002) A Cre/loxP-deleter transgenic line in mouse strain 129S1/SvImJ. Genesis 32:199-202
Szabo, Piroska E; Tang, Shih-Huey E; Reed, Michael R et al. (2002) The chicken beta-globin insulator element conveys chromatin boundary activity but not imprinting at the mouse Igf2/H19 domain. Development 129:897-904
Szabo, Piroska E; Hubner, Karin; Scholer, Hans et al. (2002) Allele-specific expression of imprinted genes in mouse migratory primordial germ cells. Mech Dev 115:157-60
Szabo, P; Tang, S H; Rentsendorj, A et al. (2000) Maternal-specific footprints at putative CTCF sites in the H19 imprinting control region give evidence for insulator function. Curr Biol 10:607-10
Szabo, P E; Pfeifer, G P; Mann, J R (1998) Characterization of novel parent-specific epigenetic modifications upstream of the imprinted mouse H19 gene. Mol Cell Biol 18:6767-76
McLaughlin, K J; Kochanowski, H; Solter, D et al. (1997) Roles of the imprinted gene Igf2 and paternal duplication of distal chromosome 7 in the perinatal abnormalities of androgenetic mouse chimeras. Development 124:4897-904
McLaughlin, K J; Szabo, P; Haegel, H et al. (1996) Mouse embryos with paternal duplication of an imprinted chromosome 7 region die at midgestation and lack placental spongiotrophoblast. Development 122:265-70
Szabo, P; Mann, J R (1994) Expression and methylation of imprinted genes during in vitro differentiation of mouse parthenogenetic and androgenetic embryonic stem cell lines. Development 120:1651-60

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