Transfer RNA

Exploring the Structure

Of course, the first thing we want to look at when examining a tRNA structure is the anticodon. The structure 2tra, an aspartate tRNA, forms a dimer in the crystal lattice, with the anticodons of two separate molecules bound together. This is shown in the upper figure. The segment from the second molecule (with carbon in green in the illustration) will give you an idea of how the codon of an RNA message would bind to the tRNA anticodon. The anticodon in this structure is composed of guanine 34, uracil 35, and cytosine 36. The lower figure shows the interaction of three bases in the structure 4tna, a phenylalanine tRNA. The cytosine and guanine form a typical base pair, just as in DNA, but a second guanine, modified with a methyl group (white sphere), forms an unusual interaction with the pair.

These illustrations were created with RasMol. You can create similar pictures by clicking on the PDB accession codes, and then choosing one of the viewing options under "View Structure."

For suggestions for further information on tRNA, click here.