Article

Role of the cytoskeleton in nuclear import.

Department of Microbiology and Immunology (MC790), College of Medicine, University of Illinois at Chicago, E-704 Medical Sciences Building, 835 S. Wolcott Avenue, Chicago, IL, USA.
Advanced Drug Delivery Reviews (impact factor: 11.5). 07/2003; 55(6):761-71. pp.761-71
Source: PubMed

ABSTRACT The role of the cytoskeleton in regulating the intracellular localization of cellular organelles, viruses, and individual proteins has been the subject of much investigation in recent years. While regulated transport through the nuclear pore remains the primary determinant of nuclear localization, it has become clear that the nuclear localization of viruses and some cellular proteins is mediated by the ability of the cytoskeleton, usually microtubules, to direct their perinuclear accumulation in close proximity to the nuclear pore complex. We also discuss how the size of virions and the viscous nature of the cytoplasm would make it very unlikely or even impossible for viruses to achieve this localization by diffusion alone in the absence of active transport mechanisms. This review focuses on the known methods employed by different viruses and proteins to effect their perinuclear accumulation.

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Keywords

active transport mechanisms
 
cellular organelles
 
cellular proteins
 
clear
 
different viruses
 
diffusion
 
individual proteins
 
intracellular localization
 
known methods
 
localization
 
microtubules
 
nuclear localization
 
nuclear pore
 
nuclear pore complex
 
perinuclear accumulation
 
primary determinant
 
recent years
 
regulating
 
viscous nature