Title:Molecular Chaperone-Mediated Nuclear Protein Dynamics
Volume: 15
Issue: 3
Author(s): Frank J. Echtenkamp and Brian C. Freeman
Affiliation:
Keywords:
Molecular chaperone, nucleus, protein-DNA dynamics, transcription.
Abstract: Homeostasis requires effective action of numerous biological pathways including those working along a genome.
The variety of processes functioning in the nucleus is considerable, yet the number of employed factors eclipses
this total. Ideally, individual components assemble into distinct complexes and serially operate along a pathway to perform
work. Adding to the complexity is a multitude of fluctuating internal and external signals that must be monitored to
initiate, continue or halt individual activities. While cooperative interactions between proteins of the same process provide
a mechanism for rapid and precise assembly, the inherent stability of such organized structures interferes with the proper
timing of biological events. Further prolonging the longevity of biological complexes are crowding effects resulting from
the high concentration of intracellular macromolecules. Hence, accessory proteins are required to destabilize the various
assemblies to efficiently transition between structures, avoid off-pathway competitive interactions, and to terminate pathway
activity. We suggest that molecular chaperones have evolved, in part, to manage these challenges by fostering a general
and continuous dynamic protein environment within the nucleus.