The long-term objective is to understand how and why mammalian cells sense, or on the other hand escape from senescence and become immortal.
The specific aims are: 1) To identify murine genes whose expression changes during senescence and/or during immortalization of mouse embryo fibroblast in cell culture. 2) To discover why these changes in gene expression have occurred and what is responsible for them. Two families of genes, one encoding MRP/proliferin and a second encoding retroviral-related sequences, show a correlation between increase expression and the acquisition of immortality by mouse embryo fibroblast inculture. They thus provide the necessary handle to identify at what level (e.g. splicing, mRNA stability) changes in gene regulation are occurring. It will be of particular interest to ascertain the role of the retroviral sequences in immortazation. The macromolecular species (protein, possibly RNA) responsible for the changes in gene expression will be isolated and characterized. It is important of understand how this (these) component(s) contribute(s) to immortalization in particular and regulation of gene expression in general. Recombinant DNA technology will be used of generate cDNA clones of MRNA from mortal and immortal cells. The libraries of molecular clones will be screened to identify specific clones corresponding to genes whose expression, as assessed by the presence or absence of the mRNA in the cytoplasm correlates with immortalization. Clones of mRNAs that disappear, or are reduced in abundance, when cells become immortal will be the maker focus, These will be candidates for a positive regulator of mortality. This project relates to all diseases in which changes in gene expression occur, notably aging and cancer. Because studies on regulation of gene expression in mammalian cells are involved, the work may impact on other areas also.

Agency
National Institute of Health (NIH)
Institute
National Institute on Aging (NIA)
Type
Research Project (R01)
Project #
1R01AG007972-01
Application #
3119343
Study Section
Molecular Cytology Study Section (CTY)
Project Start
1989-05-01
Project End
1994-04-30
Budget Start
1989-05-01
Budget End
1990-04-30
Support Year
1
Fiscal Year
1989
Total Cost
Indirect Cost
Name
Rutgers University
Department
Type
Schools of Arts and Sciences
DUNS #
038633251
City
New Brunswick
State
NJ
Country
United States
Zip Code
08901
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Hwang, S M; Lopez, C A; Heck, D E et al. (1994) Osteopontin inhibits induction of nitric oxide synthase gene expression by inflammatory mediators in mouse kidney epithelial cells. J Biol Chem 269:711-5
Malyankar, U M; Rittling, S R; Connor, A et al. (1994) The mitogen-regulated protein/proliferin transcript is degraded in primary mouse embryo fibroblast but not 3T3 nuclei: altered RNA processing correlates with immortalization. Proc Natl Acad Sci U S A 91:335-9
Hwang, S M; Wilson, P D; Laskin, J D et al. (1994) Age and development-related changes in osteopontin and nitric oxide synthase mRNA levels in human kidney proximal tubule epithelial cells: contrasting responses to hypoxia and reoxygenation. J Cell Physiol 160:61-8
Lopez, C A; Hoyer, J R; Wilson, P D et al. (1993) Heterogeneity of osteopontin expression among nephrons in mouse kidneys and enhanced expression in sclerotic glomeruli. Lab Invest 69:355-63
Rittling, S R; Denhardt, D T (1992) p53 mutations in spontaneously immortalized 3T12 but not 3T3 mouse embryo cells. Oncogene 7:935-42
Cocuzzi, E T; Walther, S E; Rajan, S et al. (1992) Expression and purification of mouse TIMP-1 from E. coli. FEBS Lett 307:375-8
Hofbauer, R; Denhardt, D T (1991) Cell cycle-regulated and proliferation stimulus-responsive genes. Crit Rev Eukaryot Gene Expr 1:247-300