Scribe: Chad Wingrave

Today's Handouts and Announcements

• Ayala, Franciso Barrio, Eladio Kwiatowski, Jan "Molecular clock or erratic evolution? A tale of two genes". Proc. Natl. Acad. Sci. vol 93, p 11729-11734, Oct 1996.

Today's Topics

• Stress Response in Plants
  • Alscher Early work
    • SOD- process that removes troubles from chloroplasts
    • found genes that worked on Fe xor Mn
    • also found some that worked on Fe and Mn
  • Current: Drought response in Loblolly Pine
• Compare kinetic evolution of SOD and Glyceral-3-Phosphate Dehydrogenase (GPDH)
  • Molecular Clock
    • thought were linear but turns out they are not
    • used by phylogenetic field to decide common ancestors ( fossils and observations)
    • turns out two different clocks can move at varying rates, and are not always linear
• Using Poisson distribution to model evolution
  • poisson - every site changes independently at a common rate
  • so given a length of time and a rate, we get the number of expected changes: ne^(-lt) where n is the length of divergence
  • so given the number of changes and the rate, we get time: = (-ln q)/2l where q is the probability that neither sequence changed

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  Today's Sources

  • Paper from above (see handouts)

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