Title: "Unraveling the nature of the segmentation clock"
Speaker: Dr. Santiago Schnell, School of Informatics, Indiana University, Bloomington, IN
Place: Mechanical Engineering (ME) 161; Tuesday, October 18, 2005; 4:30pm


Vertebrate segmentation has proven to be under a strict temporal control governed by a biological clock. The breakthrough demonstrating the cyclic oscillation of genes and proteins in the presomitic mesoderm is the first example of a molecular oscillator, a segmentation clock, working in early embryos. The mechanism driving the oscillations of the cycling genes has been intensively studied experimentally in zebrafish, chick, and mouse. However, the segmentation clock is far from well understood. The present experimental and theoretical evidence suggest that the segmentation clock initiates and maintains its periodic cycling by the periodic activation and/or inhibition of Notch signalling pathway as well as the periodic autoregulation of the cycling genes themselves. Our hypothesis is that the segmentation clock oscillations are determined by the topology of the network of genes/proteins central to the oscillator and the type of regulatory interactions between components. In order to test this hypothesis we are investigating using bioinformatics techniques the structural and interaction properties of the proteins in the segmentation clock. We are also modeling whether the topology and the regulatory interactions - known experimentally and predicted theoretically - of the components of the segmentation clock can explain the periodic expression of the cyclic genes.

Click here for a full scheule of BIOINFORMATICS SEMINARS, past and present.