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AAT Bioquest

What are three types of RNA?

Posted January 26, 2021


Answer

Three main types of RNA present in cells include messenger RNA (mRNA), ribosomal RNA (rRNA) and transfer RNA (tRNA).

  • Messenger RNA (mRNA) is a single-stranded RNA molecule responsible for carrying genetic information from the nucleus to the cytoplasm for protein synthesis by ribosomes. mRNA is transcribed in the nucleus with DNA acting as its template.
  • Ribosomal RNA (rRNA), which is a type of non-coding RNA (i.e. not translated into protein), is present in the cytoplasm of cells. It associates with ribosomal proteins to form large and small ribosome subunits, and together, these subunits are responsible for translating mRNA into proteins.
  • Transfer RNA (tRNA) is a small RNA molecule, typically 75 to 90 nucleotides long, that is present in the cytoplasm of cells. It is responsible for bringing amino acids to the ribosome that corresponds to the appropriate codon of mRNA. These amino acids are then joined together to make proteins.
Additional resources

The Three Roles of RNA in Protein Synthesis

DNA and RNA

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