Answer to Question #86124 in Biochemistry for Hans Modi

Question

What are the functional roles of tRNA and rRNA?Explain how these are structurally different and where are these RNAs found in cell?

Answer 1

tRNA or transfer RNA plays a key role in translation, the process of synthesizing proteins from amino acids in a sequence specified by information contained in messenger RNA. During this process, triplets of nucleotides (codons) of the messenger RNA are translated according to the genetic code into one of the 20 amino acids. tRNAs serve as the dictionary in this translation process. They contain a specific triplet nucleotide sequence, the anticodon, and they get attached to a specific (cognate) amino acid. During protein synthesis by ribosomes, tRNAs deliver the correct amino acids through interactions of their anticodon region with the complementary codons on the messenger RNA. Apart from their distinct anticodon regions, different tRNAs have very similar structures, allowing them to all fit into the tRNA-binding sites on the ribosome.

More information on the web-site: https://proteopedia.org/wiki/index.php/TRNA

Ribosomal RNA (rRNA),  molecule in cells that forms part of the protein-synthesizing organelle known as a ribosome and that is exported to the cytoplasm to help translate the information in messenger RNA (mRNA) into protein. The three major types of RNAthat occur in cells include rRNA, mRNA, and transfer RNA (tRNA). Molecules of rRNA are synthesized in a specialized region of the cellnucleus called the nucleolus, which appears as a dense area within the nucleus and contains the genes that encode rRNA. The encoded rRNAs differ in size, being distinguished as either large or small. Each ribosome contains at least one large rRNA and at least one small rRNA. In the nucleolus, the large and small rRNAs combine with ribosomal proteins to form the large and small subunits of the ribosome (e.g., 50S and 30S, respectively, in bacteria). (These subunits generally are named according to their rate of sedimentation, measured in Svedberg units [S], in a centrifugal field.) Ribosomal proteins are synthesized in the cytoplasm and transported to the nucleus for subassembly in the nucleolus. The subunits are then returned to the cytoplasm for final assembly.

More information on the web-site: https://www.britannica.com/science/ribosomal-RNA