The transgenic and gene knockout technology has proved to be a powerful system to elucidate in vivo functions of target genes and to establish mouse models of human diseases. However, the conventional approach introduces modifications in mouse germline, which may lead to adverse effects or may be fully compensated in development. Thus...

Hormones are well known to coordinate animal metabolism, reproduction, and homeostasis to maximize survival and reproductive success. Pioneering work in the small roundworm Caenorhabditis elegans has revealed that several hormones also impact animal longevity. Nuclear hormone receptors are transcription factors that turn on or off...

Few mammalian models of aging have the phenotype of increased life span. Virtually all work has focused on food restricted (FR) rodents. Although many changes in physiologic function and gene expression have been identified, it is difficult to determine which changes contribute significantly to life span extension. Additional models...

The major focus of my laboratory for the last 15 years has been on understanding the functions of a category of genes called tumor suppressors. As their name implies, a primary role of tumor suppressor genes is to prevent the onset of cancers. Cancers are often initiated when cells and their genes are damaged by internal or external toxins...

Epigenetics entails the study of the switching on and off of genes during development, cell proliferation and also by environmental insults. Epigenetic changes can result in the stable inheritance of a given spectrum of gene activities in specific cells. Genome modifications resulting from epigenetic changes appear to play a critical role in...

Immunosenescence is the deterioration of immune function that accompanies aging and that contributes to age-dependent increases in infection, mortality, and potentially cancer. Dietary restriction is a manipulation whereby exposing experimental animals to a reduced-calorie environment extends lifespan and retards many forms of age-associated...