SISSA COLLOQUIUM

[Alex Meehan]

SISSA COLLOQUIUM

September 24, 16:30 - Lecture Room D, SISSA main building

The seminar will be preceded by a get-together at 4.10pm in front of
room D for tea and coffee.


Dr. Silvia Onesti

Elettra and Statistical and Biological Physics Sector, SISSA

Title:
Perpetuating the double helix: molecular engines on the DNA

Abstract:
Coded in the structure of DNA is a biological message that can be 
stored, transferred, read and interpreted. Before each cell division, 
the entire DNA needs to be accurately replicated to ensure that each 
daughter cell contains an undamaged copy of the original molecule. The 
regulation of this process is particularly tricky for the more complex 
eukaryotic cells (including humans), due to the larger amount of genetic 
information.
One of the most important proteins in this process is the MCM helicase. 
We use a combination of X-ray diffraction and electron microscopy 
techniques to unravel the atomic structure and the mechanism of action 
of the MCM helicases. We can  visualise this molecular machine as a 
combustion engine that is able to harness the energy from ATP to unzip 
the DNA double helix.
The control of DNA replication is not only a fundamental biological 
problem, but has important medical consequences. Most cells in our body 
are in a quiescent state: triggering DNA replication in adults is often 
connected with unwanted proliferation (a hallmark of cancer). MCM 
helicases are only present in replicating cells, and can therefore be 
used as tumor markers and possible drug targets for cancer.