A third role is to establish specific locations or cellular addresses for which processes should occur. For example, a transcription factor may be directed to a nucleus, where it can promote transcription of certain genes. In terms of protein synthesis, the necessary organelles are relatively near one another. The nucleolus within the nuclear envelope is the location of ribosome synthesis. The destination of synthesized ribosomes for protein translation is rough endoplasmic reticulum (rough ER), which is connected to and shares the same membrane with the nucleus. The Golgi body is also near the rough ER for packaging and redistributing. Likewise, intracellular compartmentalization allows specific sites of related eukaryotic cell functions isolated from other processes and therefore efficient.