Question

The transport receptor, exportin, functions to transport:

A) RNA to the nucleus when associated with GDP-bound Ran protein.

B) RNA to the nucleus when associated with GDP-bound RNA protein.

C) RNA to the cytoplasm when associated with GTP-bound Ran protein.

D) RNA to the cytoplasm when associated with GDP-bound Ran protein.

Answer 1

Answer--

In this question option C (RNA to the cytoplasm when associated with GTP bound Ran protein) will be correct. exportin are transportor protein found in nuclear membrane.it transport several components like nuclear proteinfrom cytoplasm to nucleus and RNA from nucleus to cytoplasm.

Exportin first bind to fully proccesd RNA with the Ran-GTP complexcomplext that diffuse through NPC ( nuclear pore complex) releasing RNA in to cytosol . Ran dependent mechanism also require for the nuclear transport of ribosomal subunit through the NPC.