Which of the following statements about the import of protein to the nucleus is correct? Choose all that apply. a. An NLS can be
a monopartite or bipartite signal which includes a significant number of basic amino acids. b. GTP is required for an importin to bind to an NLS of a protein destined to be localized to the nucleus. c. Ribosomal proteins must display an NLS to be localized to the nucleus, and an NES to be localized to the nucleolus. d. The recycling of importins back to their original conformation requires GTP hydrolysis in the cytoplasm.
• a. An NLS can be a monopartite or bipartite signal which includes a significant number of basic amino acids.
• d. The recycling of importins back to their original conformation requires GTP hydrolysis in the cytoplasm.
The other answers are incorrect because GTP is not required for an importin to bind to an NLS but for the release of importin and an NES or nuclear export signal is the sequence in a protein for export from the cell nucleus to the cytoplasm, not to the nucleolus.
