A cell can control the proteins it contains by:
A.
(1) controlling when and how often a given gene is transcribed, (2) controlling how an RNA transcript is spliced or otherwise processed
B.
(3) selecting which mRNAs are exported from the nucleus to the cytosol
C.
(4) regulating how quickly certain mRNA molecules are degraded, (5) selecting which mRNAs are translated into protein by ribosomes
D.
(6) regulating how rapidly specific proteins are destroyed after they have been made; in addition, the activity of individual proteins, once they have been synthesized, can be further regulated in a variety of ways