BME Seminar Series: Prof. David Dean
Importance of Cytoskeletal Structure in Gene Delivery
Under physiologically relevant conditions, the levels of non-viral gene transfer are low at best. The reason for this is that many barriers exist for the efficient transfer of genes to cells, even before any gene expression can occur. While many transfection strategies focus on DNA condensation and overcoming the plasma membrane, events associated with the intracellular trafficking of the DNA complexes have not been as extensively studied. Once internalized, plasmids must travel potentially long distances through the cytoplasm to reach their next barrier, the nuclear envelope. By studying cells grown statically and under conditions of mild cyclic stretch, we have demonstrated that plasmids move through the cytoplasm using microtubule-associated motors. Moreover, we have found that post-translational acetylation of microtubules results in enhanced trafficking and greater transfection efficiency. Microrheological studies have begun to show that cyclic stretch also reduces cytoplasmic stiffness, which likely plays an additive role in intracellular trafficking and gene delivery.