There is no structure responsible for protein synthesis, there are many structures. Eukaryotes are different than prokaryotes. Here is eukaryote: It is a whole process: 1st something activates the transcription of the DNA into RNA. read more
All components of protein function are defined by the exact composition, structure and conformation of the proteins, which is encrypted within the DNA region (called locus) encoding that protein. With the process of protein synthesis biological cells generate new proteins, which on the other hand is balanced by the loss of cellular proteins via degradation or export. read more