A further example of how genetic instability contributes to cancer progression is recent data indicating that mutation in any one of four human mismatch repair gene homologs, MSH2. MLH1, PMS1 and PMS2, predisposes to hereditary nonpolyposis colon cancer (HNPCC). We have cloned cDNA and/or genomic sequences for three mouse MutL homologs, PMS2, MLH1 and PMS1. We have derived by gene knockouts in embryonic stem cells, mice that are heterozygous and homozygous for a PMS2 null mutation. A tumor from a homozygous animal exhibits new alleles for a number of randomly chosen microsatellite loci. Genome-wide instability of microsatellite sequences is one key feature of """"""""mismatch repair defective"""""""" sporadic tumors and tumors from HNPCC individuals. We have observed male- specific sterility in mice homozygous for PMS2 null mutation. Our overall objective is to study further the effect of """"""""null"""""""" mutations in MutL homologs of DNA mismatch repair genes. We will concentrate on homologs of the bacterial MutL gene, PMS2 and MLH1. A primary goal is to derive an animal model for a common form of human cancer, HNPCC. We will monitor tumor formation in PMS2 heterozygous and homozygous animals. We will measure microsatellite instability in these tumors. We wilt test for cooperativity between a null allele in PMS2 and different alleles of the mouse APC (adenomatous polyposis coli) gene. We will study the effect of PMS2 mutation in the male germ line. We wilt measure the frequency of mutation in CA/GT dinucleotide repeats in sperm from normal, heterozygous and homozygous mice. In these mice we will study heteroduplex DNA repair during male meiotic recombination. To examine the basis for the male- specific seen in mice homozygous for mutation in PMS2, we will evaluate spermatogenesis primarily by cytological methods, including an assessment of meiotic progression. We will measure mutation rates in cell lines established from mouse embryos that are wild-type, heterozygous or homozygous for the PMS2 null mutation. Finally, we will derive mice carrying mutations in a second mismatch repair gene, MLH1, and compare the phenotype of these mice to those with PMS2 mutation.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM032741-17
Application #
2838492
Study Section
Mammalian Genetics Study Section (MGN)
Project Start
1983-12-01
Project End
1999-11-30
Budget Start
1998-12-01
Budget End
1999-11-30
Support Year
17
Fiscal Year
1999
Total Cost
Indirect Cost
Name
Oregon Health and Science University
Department
Genetics
Type
Schools of Medicine
DUNS #
009584210
City
Portland
State
OR
Country
United States
Zip Code
97239
Fischer, Jared M; Calabrese, Peter P; Miller, Ashleigh J et al. (2016) Single cell lineage tracing reveals a role for Tgf?R2 in intestinal stem cell dynamics and differentiation. Proc Natl Acad Sci U S A 113:12192-12197
Fischer, Jared M; Dudley, Sandra; Miller, Ashleigh J et al. (2016) An intact Pms2 ATPase domain is not essential for male fertility. DNA Repair (Amst) 39:46-51
Fischer, Jared M; Schepers, Arnout G; Clevers, Hans et al. (2014) Occult progression by Apc-deficient intestinal crypts as a target for chemoprevention. Carcinogenesis 35:237-46
Fischer, J M; Miller, A J; Shibata, D et al. (2012) Different phenotypic consequences of simultaneous versus stepwise Apc loss. Oncogene 31:2028-38
Johnson, Jennifer R; Erdeniz, Naz; Nguyen, Megan et al. (2010) Conservation of functional asymmetry in the mammalian MutL? ATPase. DNA Repair (Amst) 9:1209-13
Tsao, Jen-Lan; Dudley, Sandra; Kwok, Brian et al. (2002) Diet, cancer and aging in DNA mismatch repair deficient mice. Carcinogenesis 23:1807-10
Baross-Francis, A; Makhani, N; Liskay, R M et al. (2001) Elevated mutant frequencies and increased C : G-->T : A transitions in Mlh1-/- versus Pms2-/- murine small intestinal epithelial cells. Oncogene 20:619-25
Yao, X; Buermeyer, A B; Narayanan, L et al. (1999) Different mutator phenotypes in Mlh1- versus Pms2-deficient mice. Proc Natl Acad Sci U S A 96:6850-5
Buermeyer, A B; Wilson-Van Patten, C; Baker, S M et al. (1999) The human MLH1 cDNA complements DNA mismatch repair defects in Mlh1-deficient mouse embryonic fibroblasts. Cancer Res 59:538-41
Winter, D B; Phung, Q H; Umar, A et al. (1998) Altered spectra of hypermutation in antibodies from mice deficient for the DNA mismatch repair protein PMS2. Proc Natl Acad Sci U S A 95:6953-8

Showing the most recent 10 out of 28 publications