your friend works in a biotechnology company and has discovered a drug that blocks the ability of ran to exchange gdp for gtp. what is the most likely effect of this drug on nuclear transport? your friend works in a biotechnology company and has discovered a drug that blocks the ability of ran to exchange gdp for gtp. what is the most likely effect of this drug on nuclear transport? nuclear transport receptors would be unable to bind cargo. nuclear transport receptors would be unable to enter the nucleus. nuclear transport receptors would be unable to release their cargo in the nucleus and return to the cytoplasm nuclear transport receptors would interact irreversibly with the nuclear pore fibrils.