NONSENSE CODONS Meaning and
Definition
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Nonsense codons, also known as stop codons or termination codons, are specific sequences of three nucleotides in messenger RNA (mRNA) that signal the termination of protein synthesis during translation. There are three nonsense codons in the genetic code: UAA (ochre), UAG (amber), and UGA (opal).
In the central dogma of molecular biology, the process of protein synthesis involves the conversion of mRNA into a polypeptide chain with the help of transfer RNA (tRNA) molecules. Each tRNA molecule carries a specific amino acid to the ribosome, where it binds to the corresponding codon on the mRNA. However, when a nonsense codon is encountered, instead of calling for an amino acid, it triggers the release of the newly synthesized polypeptide chain from the ribosome.
Nonsense codons play a crucial role in regulating gene expression and ensuring the accuracy and functionality of the protein synthesis process. Mutations that result in the insertion of a nonsense codon into an mRNA sequence can lead to the premature termination of protein synthesis, resulting in nonfunctional, truncated proteins. Additionally, nonsense codons are targeted by cellular quality control mechanisms, such as nonsense-mediated mRNA decay, which helps eliminate abnormal or incomplete mRNA molecules.
Overall, nonsense codons act as molecular punctuation marks, indicating the end of a protein-coding sequence and facilitating the production of fully functional proteins.
Common Misspellings for NONSENSE CODONS
- bonsense codons
- monsense codons
- jonsense codons
- honsense codons
- ninsense codons
- nknsense codons
- nlnsense codons
- npnsense codons
- n0nsense codons
- n9nsense codons
- nobsense codons
- nomsense codons
- nojsense codons
- nohsense codons
- nonaense codons
- nonzense codons
- nonxense codons
- nondense codons
- noneense codons
- nonwense codons
Etymology of NONSENSE CODONS
The term "Nonsense Codons" refers to the specific group of codons (sequences of three nucleotides) found in messenger RNA (mRNA) that signal the termination of protein synthesis during translation. The etymology of this term lies in the meaning of the individual words.
1. Nonsense: In the context of genetics, "nonsense" refers to a type of mutation that introduces a premature stop codon into the mRNA sequence. These stop codons act as signals for the ribosome to terminate protein synthesis. The term "nonsense" implies that the resulting mRNA sequence is nonsensical or lacking the necessary information for the complete synthesis of a functional protein.
2. Codons: In genetics, a codon refers to a sequence of three nucleotides (combinations of A, U, C, and G) in mRNA that specifies the addition of a specific amino acid during protein synthesis.
