Protein synthesis

translation of mRNA

Click to view another animation of the process of translation.

Once a copy of the required gene is formed, the messenger RNA(mRNA) travels out through pores in the nuclear membrane through the cytoplasm where it attaches itself to a ribosome. A template is now formed for the formation of a specific protein.

Smaller RNA molecules called transfer RNA(tRNA) pick up amino acids that float around in the cytoplasm. Each tRNA has a specific amino acid which it binds to and also has a specific triplicate base code on its surface. If the triplicate base code on the tRNA matches the codon of the mRNA, currently passing through the ribosome, a chemical bond takes place. The amino acid that is carried by the tRNA now bonds to adjacent amino acids to form the long protein chain.

See the animation above. Red represents adenine, blue represents uracil, green represents guanine and brown represents cytosine.

 

Having the code and the appropriate resources, proteins of many different shapes can be assembled. As the protein assembles it takes on a unique shape.
1) From viewing the animations above explain:
- how the genetic code on the mRNA is translated,
- what is the function of tRNA,
- how does the next item in the assembly process come to be attached,
- what happens to the protein as it grows in length,
- what the function of the ribosome is.
2) Some scientists hope to use the cell's own protein manufacturing process to build small objects in the nano range.
a) What must the scientists change or provide in order for the cell to produce a unique nano sized object?
b) What will the scientists keep the same?
Protein synthesis is analogous to car manufacturing. It may be worthwhile in comparing the two processes. Click if you wish to read the analogy.

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