Ribosomal Subunits Atomic structures of the ribosomal subunits reveal a central role for RNA in protein synthesis. The Protein Factory. Ribosomal subunits. Ribosomal RNA is essential for protein synthesis. In fact, RNA is thought to be the catalytically active part of the very large complex of proteins and RNAs tha The three roles of RNA in protein synthesis. Messenger RNA (mRNA). Ribosomal RNA (rRNA) associates with a set of proteins to form ribosomes. In molecular biology, ribosomal ribonucleic acid (rRNA) is the RNA component o the ribosome, an is essential for protein synthesis in aw livin organisms. Ribosomal RNA (rRNA), translation Encyclopædia Britannica, Inc. molecule in cells that forms part of the protein-synthesizing organelle known as a ribosome and that. RNA synthesis requires accurate and efficient initiation. In eukaryotes a 45S pre-ribosomal RNA serves as the precursor for the 18S, 28S and 5.8S rRNAs. In molecular biology, ribosomal ribonucleic acid (rRNA) is the RNA component of the ribosome, and is essential for protein synthesis in all living organisms. The hypothesis that nascent R-RNA associated with neosomes forms the unit responsible for the synthesis of ribosomal protein leads to a number of self-consisten However, it is notable that, in ribosomal RNA. also contain nucleic acids. The role of RNA in protein synthesis was suspected already in 1939. [66] The ribosomal RNA (of rRNA), a component of the ribosomal RNA, which is essential for protein synthesis in all organisms. It consists primarily of a material within.