*ITAMP Topical Lunch Discussion*
Date: Thursday, February 25th
Time: 12:00-1:30 pm
Pizza will be served.
Location: B-106 @ Center for Astrophysics (60 Garden Street)
Directions: after entering the lobby of the CfA, turn right to enter the
hallway of the B building. In the hallway, turn right again, and B-106
is there.
*Speaker:* Amy Gilson (Harvard University)
*Title: *The role of evolutionary selection on the dynamics of protein
structure evolution*
*
*Abstract:* A wide variety of proteins exist in nature. While protein
sequence evolution can be easily detected in natural sequences and
produced in the laboratory, protein structure evolution is rarely
observed and is difficult to engineer. Therefore, many questions
regarding protein tertiary structure evolution remain unanswered. For
example, how does sequence evolution translate into structure evolution?
Must proteins lose thermodynamic stability during the process of
evolving a new fold? In this work, we propose a simple analytical model
in which evolutionary transitions among protein structures follow
activated dynamics. This model is tested against Monte Carlo simulations
of model protein evolution and also population genetic simulations of
organisms evolving under Darwinian selection. An analogy between
temperature in statistical physics and population size in evolutionary
dynamics can be drawn. Indeed, these two key parameters control the
transition from diffusive to activated dynamics in the respective
simulations. Finally, we provide bioinformatic evidence that the
strength of selection under which proteins evolve has modulated rates of
protein structure evolution in nature.*
*
--
Stefan Pabst
ITAMP Postdoc
Alexander von Humboldt Fellow
ITAMP, Harvard-Smithsonian Center for Astrophysics
60 Garden Street
Cambridge, MA 02138, USA
phone: +1-617-495-7239
fax: +1-617-496-7668
email: stefan.pabst(a)cfa.harvard.edu
website:
www.stefanpabst.name