Estrogen Receptor Alpha G525L Knock-In Mice

Abstract

We are developing a knock-in' mouse model with a mutation (glycine 525 to leucine, G525L) in estrogen receptor alpha (ERalpha) that permits exogenous regulation of its ligand-induced signaling pathways. This ligand-binding pocket mutation significantly reduces ERalpha response to endogenous estrogens but not to the synthetic nonsteroidal estrogen diethylstilbestrol (DES). Therefore, ERalpha signaling pathways can be turned on and off' in these mice through DES administration or withdrawal. To generate knock-in mice, an ERalpha construct containing the G525L mutation was engineered to facilitate homologous recombination into the mouse genome. The targeting construct was electroporated into ES cells, two positive clones were injected into mouse blastocysts, chimeras were generated, and germline transmission was established. Heterozygous mice were mated to produce litters of homozygous, heterozygous, and wild type mice. Genomic DNA from homozygous animals was sequenced and confirmed the G525L mutation was present. Reproductive tissues from 5 week old heterozygous and homozygous females were analyzed. Homozygous mice had immature and hypoplastic uterine tissue and mammary gland ductal trees. Homozygous ovaries were similar to those of heterozygous animals. Further analysis of this knock-in model will provide valuable information about the role of ERalpha in mammary gland development and carcinogenesis.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 2005
Accession Number
ADA435099

Entities

People

  • Kerstin W. Sinkevicius

Organizations

  • University of Chicago

Tags

DTIC Thesaurus Topics

  • Abstracts
  • Biomedical Research
  • Demographic Cohorts
  • Embryos
  • Estrogens
  • Genetic Phenomena
  • Genetics
  • Glands
  • Hormones
  • Mammary Glands
  • Medical Personnel
  • Mutations
  • Pcr Testing
  • Polymerase Chain Reaction
  • Regulations
  • Sex Glands
  • Targeting

Fields of Study

  • Biology

Readers

  • Breast cancer cell signaling and growth regulation.
  • Molecular Biology and Genetics
  • Molecular and genetic basis of cancer.