Flavr Savr Gene Modification

NOTE: Mr. Vink! as I previously told you about the font, and you probably would have already forgotten. So, I wanted to remind you about the font being uncooperative and annoying in this blog post. You'll see some paragraphs font are larger than the other. I think it's because I wrote this blog on MS word and then copy pasted it on here. So,Please excuse the organizing component for this blog post.

Next time I'll directly post my blog through blogspot, Sorry for the inconvenience.Cheers to you and read on.

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As my previous blog post: "History and Introduction to the gene insertion" introduced the concept of how the gene insertion in Flavr Savr was done. This blog will explain of how the insertion was done on Flavr Savr in more details.

Botanical Details

Beginning with the basics of a “normal” tomato, every cell

wall of a plant contains a complex carbohydrate

known as Pectin. It helps the plant to be firm

and strong as well as help the flow of water in and out of the cell walls.

Why did I mention Pectin? It is because pectin is found in tomatoes and that is what makes the tomatoes to ripen an

d become softer or basically lose its freshness “normally”. An enzyme called Polygalacturonase triggers Pectin to do this.

So guess what the geneticists would need to do

in order to help preserve the tomato? THE EXA

CT OPPOSITE

How is the torture done?

It begins with the process of genetic modific

ation where a different/opposite gene is inserted in the happy and normal tomato.

Biological Details

So, what and how the geneticists do it?

They create an antisense oligonucleotide that does the exact opposite role of Polygalacturonase. They then insert it into the tomato as it's growing in the fields.

What is an antisense oligonucletide?

According to the Nelson 12 Biology Textbook, “an antisense oligonucleotides are short stretches of RNA that recognize and deactivate complementary mRNA molecules. If antisense RNA is produced that is complementary to the pronociceptive transmitter mRNA and then introduced into the cells. It will hyberdize to the mRNA and prevent Ribosomes from translating it into the protein” ( in our tomatoes case, the protein is polygalacturonase)

The figure below is a similar way of how the inhibition process occurs for the protein:

(“One way of visualizing this is to imagine how hard it would be for people to function if we each had a mirror image of ourselves stuck to us.”)

Back to the process, so the mental people (geneticists) insert the antisense gene into the tomatoes as they are in the process of growing. The antisense oligonucleotide does its job by interrupting the job of polygalactunorase and the result is that pectins job is slowed down causing the tomato ripening and softening process to become more delayed . The following picture shows how the process undergoes within the tomato:

(poor Tomao, he's very upset with this)

Kan-r gene against Kanamycin

As well as that, to confirm if the product is successful, another genetic modification was made. They wanted to make it resistant towards the antibiotic kanamycin. Kanamycin is used to treat bacterial infections.

(more torture ?)

So, to conform if the Flavr Savr would actually work, they created a marker gene. The marker gene is called kan-r. This gene creates a "natural occurring protein" that makes the tomato resistant to antibiotic kanamycin. So, the geneticists test it by exposing it to kanamycin and the ones with no effect are the Flavr Savr ones.

Misinformation regarding Kanamycin

It was thought that Kanamycin would cause humans to become resistant towards the actual antobiottic. However, Calgene then proved it wrong by providing some "data" showing that the kan-r gene from Flavr does not "travel to the human gut" while consumed by human "nor by the bacteria in the soil."

Calgene should have also proven that this did not cause any side affects on human...but of course they wouldn't. They only proved this because it was probably a causing them problems.

Of course, there has to be cons / issues to this whole topic of gene insertion. I will talk about that in another blog post.

THE END...for now!

-The EnviroGirl

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