You have transfected HeLa cells with a gene encoding the human immunodeficiency virus (HIV) protein Rev and have induced the expression of the protein. You incubate the cell culture in the presence or absence of leptomycin B and later measure the localization of Rev inside the cells by immunofluorescence microscopy. Leptomycin B specifically inhibits the cellular Crm1 protein, a nuclear transport receptor that is essential for the normal function of Rev in the HIV life cycle. Your results are tabulated below. Which condition (1 or 2) do you think corresponds to the presence of leptomycin B?

Question

Quizplus · Accepted Answer

By inhibiting Crm1, leptomycin B inhibits the nuclear export of Rev, resulting in its nuclear accumulation.

You Have Transfected HeLa Cells with a Gene Encoding the Human