The road much traveled: trafficking in the cell nucleus

Trafficking of RNA molecules and proteins within the cell nucleus is central to genome function. Recent work has revealed the nature of RNA and protein motion within the nucleus and across the nuclear membrane. These studies have given insight into how molecules find their destinations within the nucleus and have uncovered some of the structural properties of the nuclear microenvironment. Control of RNA and protein trafficking is now emerging as a physiological regulatory mechanism in gene expression and nuclear function.