Protein translation

In this unit we are going to learn about the protein translation. This lesson is part of the unit "Genes and their function", and has to be learned after understandig the genetic transcription.

First of all, please click the button "What are proteins?" to watch a video that makes a review about proteins (0:59 min). Under the video you can find some information about proteins and their functions.

After watching this video, we have remembered that a protein is an organic molecule that carry out most of the body's functions and consist of a long chain of amino acids. Genes, are the sequences of DNA that have the instructions to produce proteins, and for that these DNA sequences have to change into RNA sequences through the genes transcription. But, how become those RNA sequence in amino acids to form proteins? The genetic mechanism that change RNA sequences into protein sequences is called Translation.

Translation starts with the binding of a ribosome to a mRNA sequence, which is the RNA that has the instructions for building proteins. The ribosomes' function is to read the mRNA in groups of three nucleotides (A, U, C or G) and assemble the pertinent transfer RNA (tRNA) to this treble of nucleotides called codon. Each tRNA has an amino acid and just can detect one single codon and bind to it. The codons that encode for each amino acid can be found clicking on the button "More information about translation".

After the ribosome's binding, it moves to the codon that codify for methionine and a tRNA with the amino acid methionine is assembled to the ribosome, forming the initiation complex. Then, the ribosome moves to the next codon binding the other amino acids until finding the codons that make the ribosome release the mRNA and the amino acid sequece.

If you want to learn more or receive an explanation from another point of view click the button "More information about translation". That is a link to the Khan Academy web page were you can find a video about the translation and a longer explanation of translation, ribosomes, tRNA and the genetic code.

Now is time to strengthen our knowledge about transcription and translation. You can find two more buttons in this unit. The first one, "Activity", redirects you to a game where you have to transcript a DNA sequence into a RNA sequence, and then choose the right codons to form a protein. Please, play and reinforce your knowledge.

The second one, "What makes a firefly glow?", is a video (1:48 min) that explains how a gene is transcript and then translate into an amino acid sequence to form the protein that makes a firefly glow. Try to detect in the video the name of that gene, the name of the protein and the different steps of the translation.