Gene expression requires that DNA plasmid cross the cell membrane and enter the cell cytoplasm, migrate to the cell nucleus and penetrate the nuclear envelope, and finally utilize the cellular transcription/translation machinery. The exact mechanism of internalization has not been determined. Several possible routes of internalization have been hypothesized, including endocytosis, fusion, and lipid-mediated transmembrane translocation (poration). While endocytosis is generally believed to be the predominant pathway into the cell, further work is needed to define the mechanism and optimize gene delivery systems. Likewise, the entry of DNA plasmid from the cytoplasm into the cell nucleus is poorly understood. In addition to active trafficking, the use of endogenous cationic material by the cell to complex DNA and facilitate transfer of the material into the nucleus cannot be ruled out at this time.

Note
Custom formulation and packaging is available for tranfection reagents in bulk quantities. Contact a product specialist to discuss your application and requirements.

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