Anticodon

Definition

An anticodon is a sequence of three nucleotides in transfer RNA (tRNA) that pairs with a complementary codon in messenger RNA (mRNA) during protein synthesis. This pairing is crucial as it ensures that the correct amino acid is added to the growing polypeptide chain, facilitating accurate translation of genetic information into functional proteins.

5 Must Know Facts For Your Next Test

1. Each tRNA molecule has a specific anticodon that corresponds to an amino acid, allowing for the precise translation of the genetic code.
2. The pairing between the anticodon and codon follows base-pairing rules, where adenine (A) pairs with uracil (U), and cytosine (C) pairs with guanine (G).
3. Anticodons are critical for maintaining fidelity in protein synthesis; incorrect pairing can lead to the incorporation of the wrong amino acid, potentially affecting protein function.
4. Anticodons are read by the ribosome in the 5' to 3' direction, ensuring that the correct amino acids are added in the right order during translation.
5. The recognition of codons by anticodons allows for the process of translation to occur, resulting in the formation of polypeptides based on the sequence encoded in mRNA.

Review Questions

• How does an anticodon ensure the accuracy of protein synthesis?
  • An anticodon ensures accuracy in protein synthesis by specifically pairing with its complementary codon on mRNA. This interaction allows tRNA molecules to deliver the correct amino acids to the ribosome, where proteins are assembled. If there is a mismatch between an anticodon and a codon, it can lead to incorrect amino acid incorporation, which may disrupt protein structure and function.
• Discuss the role of tRNA and its anticodon in the overall process of translation.
  • tRNA plays a vital role in translation by carrying amino acids to the ribosome, where proteins are synthesized. Each tRNA molecule has an anticodon that matches a specific codon on mRNA. As the ribosome moves along the mRNA strand, tRNAs sequentially bind to their respective codons through complementary base pairing, ensuring that amino acids are added in the correct order. This process is essential for translating genetic information into functional proteins.
• Evaluate how mutations affecting anticodon-codon pairing might influence protein function and cellular processes.
  • Mutations affecting anticodon-codon pairing can have profound impacts on protein function and cellular processes. If a mutation alters an anticodon such that it pairs incorrectly with a codon, it could result in the incorporation of an incorrect amino acid into a protein. This misincorporation can lead to dysfunctional proteins that may lose their activity or gain harmful properties. Such changes can disrupt cellular functions, potentially contributing to diseases or metabolic disorders.

Related terms

Codon: A codon is a sequence of three nucleotides in mRNA that specifies a particular amino acid or signals the termination of protein synthesis.

tRNA:

Transfer RNA (tRNA) is a type of RNA that transports specific amino acids to the ribosome during protein synthesis, matching its anticodon with the corresponding codon on mRNA.

Ribosome: A ribosome is a molecular machine made of ribosomal RNA and proteins, responsible for synthesizing proteins by facilitating the interaction between mRNA and tRNA.