Nuclear structure and function

The Minisymposium on Nuclear Structure and Function featured new strategies and approaches for understanding how the vast amount of information in the nucleus is parsed out in individual cells. The field faces the problem of deducing the structure of a dynamic polymer (chromatin) in a living cell. Classical structural biology approaches have not been as forthcoming for dissecting the structure of this highly flexible and dynamic polymer. From a statistical mechanics perspective, the number of states that chromatin can adopt provides a rich source of conformational energy. Extrapolating to nuclear domains, we appreciate these are statistical definitions for regions within the nucleus that are on average differentiated from adjacent regions. Nuclear domains are not confined by membranes; rather, they are more like eddies in a highly viscous environment that provide chemistry favoring one chromatin state over another. The question is how we probe subtle features in such a fragile environment as the cell.