(56)
6. Angive at kodons i mRNA er komplementære til og læses af anticodons i tRNA
Devlin, s.236, fig. 6.1
Devlin, s.79
Stryer, s.831-832

Translation of the codons in mRNA involves direct interaction between the codon sequences of mRNA with complementary anticodon sequences in tRNA. Each of the bases of the codon forms a Watson-Crick type of base-pair with a complementary base on the anti-codon. The codon and the anticodon would then be lined up in an antiparallel fashion.

The anti-codon region in tRNA is an unpaired, base stacked loop of seven nucleotides. The partial helix cause by base stacking in this loop binds, by base pairing, to the complementary codon in mRNA. 

Each tRNA species carries a unique amino acid, and each has a specific three-base anticodon sequence. When the codon-anticodon interaction is made, the amino-acid is incorporated into the growing polypeptide chain.

The amino-acid in aminoacyl-tRNA does not play a role in selecting a codon. The codon is strictly selected by complementary codon-anticodon base pairing.

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