Science Buddies: "Ask an Expert"

I need to know what is the general aim from tissue culture , And how it can affect the plant , and if it can change its biochemical and genetic acticity ???

Hi Aliaa,

I'm not sure if I understand your question. Plant tissue culture is a way to make new plants from small bits of a mother plant. The new plants are identical clones of the original plant, so they should be identical in other ways as well.

You could change the biochemistry of a plant by changing certain genes. That's what a genetic engineer does in creating new forms of plants that have pest resistance or enhanced nutritional qualities. Is that what you are interested in using plant tissue culture for?

We will be pleased to help get you started on a good project if you could tell us more specifically what question you are thinking of asking.

Repost to this same thread with your ideas and we can go from there.

Best wishes,

Sybee

Thank you for your help !
I thought first of changing the genes of a plant to Increase the production of a certain element and to adapt with certain condtions and soil , And i wanted to know what is tissue culture and if it can help , but now i think tissue culture is not what i want to do , I want to know how can i change genes of a plant

Hi Aliaa,

Genetic engineering and genetic modification are a hot topic in research and policy right now. Some people think it is a great idea and some people call it 'Frankenfood'. Whatever we think about GMO plants and animals, they are going to be made because there is a need for them.

The question you asked is how you can modify the genes of a plant. Well, first you have to decide WHY you want to change a particular gene. Do you want the plant to be resistant to an herbicide like those that have been genetically modified to resist glyphosate, the chemical in RoundUp? Do you want a tomato that ripens faster and tastes better? How about a GMO corn that requires less fertilizer?

Changes to the DNA in genes is at the heart of evolution and nature has been doing this through DNA mutations for a billion years. That is how plants and animals and fungi and bacteria all adapt to their environment. It is only since the discovery of DNA as the genetic material that people have thought about doing mutations themselves rather than just crossing and breeding plants and animals to get the desired traits.

Mutations--changes in the base sequence in a gene--can be caused by radiation or certain chemicals but nowadays researchers can create the changed DNA synthetically and simply insert it into the gene. This gives them much better control over the change and avoids damage to other genes by the radiation or chemicals.

Now what can you do? That depends on specifically what you are interested in. Genes control everything so everything can be changed. You said that you might like to increase the yield of a crop plant or increase its production of something. I would suggest you pick a specific plant like soybeans or cotton or carrots and do some online research on their genetic modifications to see what others have done or thought about.

As a genetic engineer, you need to first identify the genes that are involved in the process that you are trying to change, then figure out how to modify the DNA to accomplish the change. This is really hard! The lab work necessary to create a GMO takes a long time and lots of expensive equipment, but it will never happen until the scientist knows exactly which base pairs need to be changed and how they need to be changed. This preliminary sequence analysis can now mostly all be done with computers so you don't even need a lab (see Genetic Engineering wiki, http://en.wikipedia.org/wiki/Genetic_engineering)

OK. I've given you lots of information, now you need to tell us what you want to do to make a project out of this. If you have access to a university molecular biology lab and a mentor to guide you and lots of time then you could actually make a genetically modified organism. Otherwise, you can develop an online feasibility study as the first part of a GMO project for later and work out the genes and modification that you would have to do and how you would test them in the lab.

Good luck and do let us know soon what you decide.

Best wishes,

Sybee

Thank you Very much !
I want to Make GMO , I decided what I i wil do , And I've searched About genetic engneering , But I don't now how to begin or what exactly should i begin with .
I've also downloaded Genome compiler , But I couldn't understand anything in it actually , I think i should know many things before using it , But I don't know what to begin with espcially that I don't know much about Genetic engineering and this stuff

Hi Aliaa,

When I was first learning genetics in college we worked with bacteria because they are a lot simpler than higher organisms. They are easy to grow and mutate. They can be ‘engineered’ quite easily and can do some pretty amazing things like digest oil spills, make fuel and generate electricity. If you want to try your hand at genetic engineering then I would suggest you pick a bacterial species and try to make it do something by mutating its DNA.

For example, here’s a story about a Chinese girl who discovered a bacterium that can break down the plastic in styrofoam cups and won the People’s Choice award at the 2009 Intel International Science & Engineering Fair

http://www.mnn.com/green-tech/research- ... -bacterium#

Other ideas for engineered bacteria are to make a kind of fuel oil called ‘biodiesel’ http://www.bbc.co.uk/news/science-environment-22253746

This was done by using the common human intestinal bacterium Escherichia (‘E.’) coli and modifying certain genes to produce oil almost identical to what is made from petroleum. You could do something like that—try to create a mutant of E. coli that makes more oil or makes it faster.

There’s really no limit to what bacteria can be engineered to do. Cyanobacteria have a kind of chlorophyll like plants so they can make their own food by photosynthesis. Photobacterium phosphoreum can make its own blue-green light. Maybe you could turn it into a biological flashlight!

I hope these ideas can spark some plan in your mind for engineering a highly useful organism. Think about it, read about it, plan it and let’s DO IT! We’re here to help you design a great science project.

Best wishes,

Sybee

Thank u !
but how can corn require less fertilizers ??!
and how am i going to identify the genes that are involved in the process that iam trying to change ?? , and if will it work if i use the GE to multiply a certain gene ??

Hello again,

Food crops such as corn have been developed over a thousand years to produce larger and sweeter ears, but this has all been done by selective breeding which takes a LONG time. Genetic engineering now offers us the means to make very specific changes to plants and animals very quickly. But, as you said, the big problem is identifying WHICH genes to change and HOW to change them.

Nitrogen is an element that all plants [and animals for that matter] need to grow and reproduce. Most crops get their nitrogen today from chemical fertilizers that are expensive and potentially harmful to the environment. Remember when I talked to you about bacteria—well there is a type of bacteria that can take nitrogen from the atmosphere and turn it into a form that plants can use. The process is called ‘fixation’ because the gaseous nitrogen is now held in a solid form as nitrate which plants can use.

So this sounds great, right? Just let the nitrogen-fixing bacteria do all the work of producing fertilizer for us. The problem is that these bacteria live in the soil in nodules on the roots of only a few types of plants—beans, mostly—and the bacteria are very picky. They won’t associate with other plants like corn. So, the idea is to engineer corn by changing certain of its genes so that it WILL be able to get together with the bacteria. Maybe we can only supply half the corn’s nitrogen needs, but still that would be a huge savings in fertilizer when you think about how much corn is grown just in this country. Here’s more info about this if you are interested: http://www.biofortified.org/2013/04/an- ... riculture/

I used nitrogen fixation as one example of what a genetic engineer could do, but there are zillions of other possibilities. Most of the current genetic modifications have to do with creating herbicide or insect resistance, but there are some that improve the flavor and enhance nutrient content [http://www.gmo-compass.org/eng/grocery_shopping/crops/].

If you want to design a food crop that requires less nitrogen, a bacterium that digests Styrofoam or chickens that grows faster, the first thing you have to do is identify which genes are part of that process. Sometimes the genes are known and sometimes only a few of them have been identified or none at all [http://www.nature.com/scitable/topicpag ... ps-and-732].

You will have to choose a plant or animal that has been studied by scientists for a long time and do a literature search using google scholar, PubMed, BioOne, WorldWideScience and others. This will be the hardest part of the project because a lot of publications are very technical and use terms and concepts you are probably not familiar with. And this is just the planning stage! Then there are many genetic engineering problems that have to be considered before an attempt can be made to actually create the desired organism.

I don’t know what you want to do but I do know you are limited by time, resources and lack of knowledge of genetic engineering. Read, read, read! That’s my advice for now. Try to understand how a database can be searched online to find the genes that might be involved in insect or herbicide resistance or enhanced nutrition. You cannot make a GMO without knowing which genes need to be modified and how.

Study genetic engineering some more then get back to us and we will help you ‘engineer’ a great project!

Best wishes,

Sybee

Thank You Very Much !
What about increasing the crop yield , can it be done with increasing the number of genes that controls the crop production ?
Or there's another way for increasing the crop yield ??

The yield of a crop depends on a lot of things--rain, fertilizer, weed competition, insect predation and plant diseases. Genetic engineers have already inserted genes for resistance to herbicides so weeds can be killed without harming the crop plants. Plants such as tomatoes have been bred for resistance to various bacterial and viral diseases for many years.

If you want to create a genetically-modified organism, a GMO, in a relatively short amount of time then crop plants are out of the question. You could do it using bacteria or yeasts or possibly nematodes or water fleas (daphnia). I would use the gene for green-fluorescent protein (GFP) as the gene to transfer because you can see it glowing under certain light.

What is the question that you would like to ask that relates to genetic engineering? You have to state your hypothesis before you can even begin to decide on the experiments.

Let us know what you are planning and we will guide you into a particular project.

Sybee