In vivo DNA is partitioned into discrete domains, either as complete closed circular molecules or as loops within linear molecules. This imposes a topological constraint on each domain by which its linking number is fixed. (The linking number is the number of times either strand links through the loop formed by the other strand.) The value of this linking number is carefully regulated by enzymes. Many important biological events are modulated by the topological state of the domain involved, including the initiation of gene expression and of DNA replication.
This workshop will focus on the topological aspects of DNA structure and function that are of greatest biological importance. Topics covered will include the nature of the topological constraints on DNA, and how the resulting stresses affect the folding and the helical structure of the DNA. Dynamical, statistical and mechanical approaches to the analysis of topologically constrained DNA structures will be presented. In addition, topological methods used to determine the mechanisms of activity of enzymes that transiently cut and rearrange DNA strands will be described.
The following speakers will give lectures in this workshop: