A new protein with a molecular weight of 25,000 Da is discovered and found to reside only in the nucleus.For this to happen, the protein must
A) be made in the nucleolus.
B) be transported across the nuclear envelope.
C) contain a large number of hydrophobic amino acids.
D) exist in a denatured state.
E) be synthesized by a unique mechanism.

Question

Quizplus · Accepted Answer

Proteins that reside in the nucleus are generally transported across the nuclear envelope, which consists of the inner and outer membranes. Small molecules (less than 60 kDa) can pass through nuclear pores, but larger proteins must be actively transported across the envelope through the nuclear pore complex. Therefore, option B is the correct answer. Options A, C, D, and E are not relevant to the localization of the protein in the nucleus.

A New Protein with a Molecular Weight of 25,000 Da