The Components and Functions of Ribosomal Ribonucleic Acid,

1990 WordsJan 26, 20188 Pages
Ribosomal ribonucleic acid, or rRNA, is the principle component of the ribosome and is crucial in the development of proteins for living cells. Approximately 80-85% of a cell’s total RNA is made up of rRNA. The low molecular weight transfer RNA (tRNA), which aids in bringing amino acids to the site of ribosomal translation, comprises only 15-20%. The remaining 1-5% is made up by messenger RNA (mRNA), which is essentially the encoding blueprint for the synthesis of a given protein. Proteins are comprised of particularly assembled amino acid chains – the instructions for proper sequencing of these chains are found within the cell’s genome. Transcription of the DNA into RNA is the first step towards protein production. This occurs in the nucleus of the cell and undergoes RNA splicing to produce mRNA (Transcription, 2014). In addition to the removal of introns, mature mRNA will also exhibit the addition of a 5’ cap and a 3’ poly(A)-tail. This cap provides resistance to 5’ exonuclease activity and protects the mRNA from degradation on that end. The cap also serves as an important binding site for ribosomes during translation, and aids the transport of mRNA through the nuclear membrane into the cytoplasm. Similar to the 5’ cap, the poly(A)-tail also helps prevents degradation of the mRNA and may help facilitate the movement of mRNA into the cytoplasm. Translation of the newly synthesized mRNA occurs in the cytoplasm, through coordination of the ribosome and other
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