7 Which of the following statements about a protein function

7. Which of the following statements about a protein functioning in the nucleus is true?

a) The nuclear protein contained a sequence that directed its import into the nucleus after completion on a membrane-bound ribosome.

b) The nuclear protein could have been synthesized by a ribosome bound to the outer membrane of the nuclear envelope.

c) The nuclear protein contained a “signal sequence” that ensured translation would be completed on the R.E.R. membrane.

d) The nuclear protein’s translation may have been completed in the nucleolus.

e) None of the above

Solution

Answer. A. The nuclear protein contained a sequence that directed its import into the nucleus after completion on a membrane-bound ribosome.

The nuclear protein contains a signal peptide of positively charged amino acid which is recognised by the importin protein which helps in the import of the nuclear protein