Investigation of the p53-dependent apoptosis versus arrest decision through analysis of Prep gene regulation

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 2003.

Bibliographic Details
Main Author: Reczek, Elizabeth E. (Elizabeth Emily), 1975-
Other Authors: Tyler Jacks.
Format: Thesis
Language:eng
Published: Massachusetts Institute of Technology 2006
Subjects:
Online Access:http://hdl.handle.net/1721.1/29595
_version_ 1826213730258518016
author Reczek, Elizabeth E. (Elizabeth Emily), 1975-
author2 Tyler Jacks.
author_facet Tyler Jacks.
Reczek, Elizabeth E. (Elizabeth Emily), 1975-
author_sort Reczek, Elizabeth E. (Elizabeth Emily), 1975-
collection MIT
description Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 2003.
first_indexed 2024-09-23T15:53:54Z
format Thesis
id mit-1721.1/29595
institution Massachusetts Institute of Technology
language eng
last_indexed 2024-09-23T15:53:54Z
publishDate 2006
publisher Massachusetts Institute of Technology
record_format dspace
spelling mit-1721.1/295952019-04-12T09:53:44Z Investigation of the p53-dependent apoptosis versus arrest decision through analysis of Prep gene regulation Analysis of Prep gene regulation : implications for p53-dependent apoptosis versus arrest decision Reczek, Elizabeth E. (Elizabeth Emily), 1975- Tyler Jacks. Massachusetts Institute of Technology. Dept. of Biology. Massachusetts Institute of Technology. Dept. of Biology. Biology. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 2003. Includes bibliographical references. The p53 tumor suppressor gene is thought to play a critical role in the maintenance of genetic integrity by virtue of its ability to check the growth of abnormal or damaged cells through initiation of the cell cycle arrest and apoptosis pathways. p53 itself is mutated in roughly half of all human tumors and is likely to be inactivated through mutations in other components of the stress response pathway in the remaining cases, highlighting the centrality of p53 function to effective tumor suppression. The vast majority of p53 mutations disrupt its sequence-specific DNA binding function, compromising its ability to activate a large array of target genes involved in apoptosis, arrest, DNA repair, senescence, differentiation and other cellular functions. While the catalog of target genes is rapidly expanding, our understanding of the effector pathways downstream of p53 and the regulatory networks that govern their expression remains incomplete. Subtle changes in cellular environment and cell type specific factors can drastically affect the decision to pause and repair accumulated damage, or to commit cellular suicide to prevent the propagation of damaged genetic material. Our understanding of this life or death decision is still rudimentary. The work presented here represents an attempt to uncover mechanisms underlying the decision to initiate apoptosis or cell cycle arrest in a simple model system. Mouse embryo fibroblasts normally respond to DNA damage by undergoing cell cycle arrest, but can be sensitized to initiate p53-dependent apoptosis by the oncoprotein E1A. Through a subtractive hybridization screen, the Perp gene was identified as a transcript strongly upregulated in cells initiating p53-dependent apoptosis compared to those undergoing cell cycle arrest. (cont.) This pattern of expression is strikingly different from those of other p53 target genes, many of which are induced to similar levels under both conditions. This finding suggested that Perp might be involved in initiation of apoptosis and that analysis of Perp regulation by p53 could provide insight into how p53 activity is modulated to affect two very disparate responses. In our examination of the Perp locus we have identified four putative p53 response elements with differing characteristics in several in vitro and in vivo assays and have shown that p53 can distinguish Perp from other target genes at the level DNA binding to these sites. These findings demonstrate that p53 plays an active role in determining the fate of the cell during the stress response and that intrinsic differences in p53 response elements of target genes determine which effectors are activated under particular conditions. A model for p53-dependent apoptosis and arrest and the implications for future research will be discussed. by Elizabeth E. Reczek. Ph.D. 2006-03-24T16:05:49Z 2006-03-24T16:05:49Z 2003 2003 Thesis http://hdl.handle.net/1721.1/29595 52916121 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 230 leaves 10095503 bytes 10095309 bytes application/pdf application/pdf application/pdf Massachusetts Institute of Technology
spellingShingle Biology.
Reczek, Elizabeth E. (Elizabeth Emily), 1975-
Investigation of the p53-dependent apoptosis versus arrest decision through analysis of Prep gene regulation
title Investigation of the p53-dependent apoptosis versus arrest decision through analysis of Prep gene regulation
title_full Investigation of the p53-dependent apoptosis versus arrest decision through analysis of Prep gene regulation
title_fullStr Investigation of the p53-dependent apoptosis versus arrest decision through analysis of Prep gene regulation
title_full_unstemmed Investigation of the p53-dependent apoptosis versus arrest decision through analysis of Prep gene regulation
title_short Investigation of the p53-dependent apoptosis versus arrest decision through analysis of Prep gene regulation
title_sort investigation of the p53 dependent apoptosis versus arrest decision through analysis of prep gene regulation
topic Biology.
url http://hdl.handle.net/1721.1/29595
work_keys_str_mv AT reczekelizabetheelizabethemily1975 investigationofthep53dependentapoptosisversusarrestdecisionthroughanalysisofprepgeneregulation
AT reczekelizabetheelizabethemily1975 analysisofprepgeneregulationimplicationsforp53dependentapoptosisversusarrestdecision