In the cytoplasm, ribosomal RNA and protein combine to form a nucleoprotein called a ribosome. It binds to the 50S subunit of the bacterial ribosome, thus inhibiting translation of mRNA. It binds to the 30S subunit of the bacterial ribosome. Both of these polymerases are important for ribosome biogenesis. The binding site of the ribosome on the rough endoplasmic reticulum is the translocon. Presence of a ribosome quality control protein Rqc2 is associated with mRNA-independent protein elongation. It is best known as the site of ribosome biogenesis. There are several levels of regulation including translation initiation, mRNA turnover and ribosome loading. The acetylation prevents chloramphenicol from binding to the ribosome. It does this by binding to the 40S subunit of the ribosome. An increased rRNA concentration serves as a negative feedback mechanism to ribosome synthesis. The mature mRNA finds its way to a ribosome, where it gets translated. Protein synthesis resumes as SRP is released from the ribosome. There are three sites on the ribosome for tRNA binding. The complete ribosome (80S) then commences translation elongation.