Webcast Lectures

Webcast Lectures

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Lecture One—Biology in Four Dimensions

Most organisms have internal clocks—molecular timepieces that control sleep, body temperature, and many other functions. Even in the absence of external cues, internal clocks operate on about a 24-hour cycle. In this lecture, Dr. Joseph S. Takahashi discusses why and how these circadian (meaning “about a day”) timekeepers evolved. Reviewing pioneering and current research, he describes the characteristics of these clocks and the role of the nervous system in producing and controlling circadian rhythms.

Lecture Two—Unwinding Clock genetics

Dr. Michael Rosbash describes genetic advances in circadian rhythms research. The breakthrough in understanding the molecular basis of circadian rhythms came for the fruit fly, Drosophila melanogaster. Using the tools of molecular genetics, Dr. Rosbash and his collaborator Dr. Jeffrey Hall cloned the first circadian rhythm gene, which they named period, or per.

Lecture Three—PERfect TIMing

The discovery and cloning of several key circadian genes in Drosophila melanogaster have greatly increased our understanding of the ways the circadian clock operates and adjusts to the outside world. In this lecture, Dr. Rosbash explains the current view of how the known genes and their proteins work together to produce the timekeeper in Drosophila. In a feedgack loop with a 24-hour rhythm, specialized clock genes are switched on and off by the proteins they encode.

Lecture Four—The Mammalian Timekeeper

As more circadian clock genes are found—among diverse species—our picture of the underlying mechanisms of circadian clocks grows more complicated. In this lecture, Dr. Takahashi will discuss recent circadian gene discoveries and highlight the similarities and differences between the circadian clock in Drosophila and the clock in mammals.

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