RNA is a type of nucleic acid called ribonucleic acid. The RNA nucleotides are joined to form a single strand.
The nucleotides are joined by a bond between the sugar of one nucleotide and the phosphate of the next.
TYPES of RNA
- Messenger RNA (mRNA).
- This is formed in the nucleus of the cell.
- It rewrites the sequence of bases of a section of DNA in a process called transcription.
- mRNA carries the code for building a specific protein from the nucleus to the ribosomes in the cytoplasm. That is, it acts as a messenger.
- Transfer RNA (tRNA)
- This is found in the cytoplasm.
- The tRNA picks up specific amino acids from the cytoplasm and brings them into position on the surface of a ribosome where they can be joined together in specific order to make a specific protein.
- This process is called translation.
- Ribosomal RNA (rRNA)
- These move along an mRNA molecule, and catalyse the assembly of amino acids into protein chains.
- They also bind tRNAs
mRNA with incorrect codons results in a faulty CFTR protein. But the faulty protein in one mRNA will only affect that specific mRNA strand – yet the faulty protein is evident in all the epithelial cells! Therefore, the problem must arise when the DNA replicated its errors.