Question

Which of these actions occur(s) commonly at a nuclear pore complex? Choose one or more:

a)Nuclear import receptors enter from the cytosol.
b)Nuclear import receptors are exported to the cytosol.
c)Proteins with a nuclear localization signal enter at the same time that proteins with a nuclear export signal exit.
d)mRNA molecules are exported to the cytosol.
e)Protein complexes diffuse into the nucleus.
f)Small water-soluble molecules are selectively transported into the nucleus.

Answer 1

Common actions at the nuclear pore complex include the entry of nuclear import receptors with proteins carrying nuclear localization signals and the export of mRNA to the cytosol. Proteins with nuclear export signals and small water-soluble molecules are also transported through these pores.

Step-by-step explanation:

The actions that commonly occur at a nuclear pore complex include several processes:

• Nuclear import receptors enter from the cytosol carrying proteins with nuclear localization signals.
• mRNA molecules, after being processed in the nucleus, are exported to the cytosol.
• Proteins with nuclear export signals are transported out of the nucleus.
• Small water-soluble molecules can also be selectively transported into the nucleus.

Proteins with a nuclear localization signal bind to nuclear import receptors in the cytosol and enter the nucleus, where ATP hydrolysis drives their active transport against a concentration gradient. mRNA molecules bound to nuclear transport receptors and associated proteins are exported through the nuclear pores into the cytoplasm where they can be translated into proteins.