Dr. Joseph Takahashi

Dr. Joseph Takahashi is the Walter and Mary Elizabeth Glass Professor in the Life Sciences, an Investigator of the Howard Hughes Medical Institute, and Director of the Center for Functional Genomics at Northwestern University. His laboratory has more than 21 years of experience studying the cellular and molecular bases of circadian rhythms in vertebrates. His group, in collaboration with Fred Turek and Lawrence Pinto at Northwestern University and William F. Dove at the University of Wisconsin at Madison, used N-ethyl-N-nitrosourea (ENU) to conduct a chemical mutagenesis screen in mice for circadian clock mutants. This initial screen led to the identification of the first circadian mutant in mice, called Clock. Using a combined approach of positional cloning and transgenic rescue, the Clock gene was identified at the molecular level in 1997. The Clock gene is a novel member of the basic-helix-loop-helix (bHLH)/Per-ARNT-Sim (PAS) family of transcription factors. It represents the first mammalian clock gene to be cloned and was the third clock gene to be described in animals (including period and timeless in Drosophila). The Clock gene has provided an important molecular entry point for the elucidation of the circadian clock mechanism and has led to the identification of a conserved pathway for the circadian oscillator that now includes nine genes. Moreover, Clock represents a “proof of principle” that forward genetics can be used in mice for discovery of genes regulating the nervous system and behavior. Takahashi was elected a member of the National Academy of Sciences in 2003. More information...