The nucleolar detention pathway: A cellular strategy for regulating molecular networks.

Molecular dynamics ensures that proteins and other factors reach their site of action in a timely and efficient manner. This is essential to the formation of molecular complexes, as they require an ever-changing framework of specific interactions to facilitate a model of self-assembly. Therefore, the absence or reduced availability of any key component would significantly impair complex formation and disrupt all downstream molecular networks. Recently, we identified a regulatory mechanism that modulates protein mobility through the inducible expression of a novel family of long noncoding RNA. In response to diverse environmental stimuli, the nucleolar detention pathway (NoDP) captures and immobilizes essential cellular factors within the nucleolus away from their effector molecules. The vast array of putative NoDP targets, including DNA (cytosine-5)-methyltransferase 1 (DNMT1) and the delta catalytic subunit of DNA polymerase (POLD1), suggests that this may be a common and significant regulatory mechanism. Here, we discuss the implications of this new posttranslational strategy for regulating molecular networks.