Synthesis of an immunoglobulin in membrane-bound or secretory form is determined by

The regulation of gene expression is not confined to the differential transcription of DNA. Even if a paicular RNA transcript is synthesized, there is no guarantee that it will create a functional protein in the cell. To become an active protein, the RNA must be (1) processed into a messenger RNA by the removal of introns, (2) translocated from the nucleus to the cytoplasm, and (3) translated by the protein-synthesizing apparatus. In some cases, the synthesized protein is not in its mature form and (4) must be posttranslationally modified to become active. Regulation can occur at any of these steps during development.