p53 and Beclin 1 in Caenorhabditis elegans are involved in cell death and DNA damage repair

Item

Title
p53 and Beclin 1 in Caenorhabditis elegans are involved in cell death and DNA damage repair
Identifier
d_2009_2013:8cdf84e3392d:11732
identifier
12361
Creator
Gamss, Sandy,
Contributor
Jill Bargonetti
Date
2013
Language
English
Publisher
City University of New York.
Subject
Biochemistry | Molecular biology | Cellular biology | Beclin 1 | C. elegans | p53
Abstract
p53 is a key regulator of growth arrest, DNA repair, apoptosis, and autophagy in response to cellular stress in animals as diverse as Caenorhabditis elegans and humans. In mammals, p53 functions as a key tumor suppressor protein that promotes removal of potentially tumorigenic cells. p53 is mutated or deleted in over 50% of all mammalian tumors and these tumors are highly resistant to available therapies. Therefore, identifying therapeutic agents and cell death pathways that promote p53-independent cell death is vital to the future of cancer therapy. We are interested in identifying how the alkylating agent, 10-decarbomyl mitomycin C (DMC) promotes p53-indpendent cell death. To answer this question, we used a C. elegans as a model system to identify known and novel cell death genes involved in DMC-induced death. C. elegans have an orthologue of p53, cep-1, that functions in germline cell death in a similar way to p53 in apoptosis. The germline in C. elegans has both mitotic and meiotic cells and displays CEP-1/p53-dependent cell death in response to UV. We examined both germline cell death and transcript levels of CEP-1 target genes in C. elegans. We found that DMC increased CED-1::GFP positive cells and DNA lesions in the absence of CEP-1 while UV required CEP-1 for germline cell death but not nuclear lesion formation. More lesions were seen over time in cep-1(gk138) mutant worms leading to the idea that CEP-1 is involved in DNA repair. Additionally, we examined the role of autophagy in cell death and DNA damage and saw that initially the knockdown of bec-1 required CEP-1 for increases in germ cell death. However in the F1 generation of bec-1 RNAi knockdown animals, the observed increase in cell death was due to a lack of clearance. Furthermore, bec-1 knockdown resulted in the increase of DNA lesions in worms with UV damage.
Type
dissertation
Source
2009_2013.csv
degree
Ph.D.
Program
Biochemistry