Monday, August 8, 2011
Researchers at Salk Institute have mapped the genome sequence of a plant - that leads the way for widespread implications for agriculture and possibly human medicines.
Researchers at Salk Institute have mapped the genome sequence of a plant - that leads the way for widespread implications for agriculture and possibly human medicines. Find out how the "little weed that could" has given researchers the tool they need to engineer plants to help feed people around the world.
Dr. Joe Ecker, Professor, Plant Biology Lab, Salk Institute
FUDGE: This is KPBS Midday Edition. I'm Tom Fudge. In the 1960s and '70s, a green revolution increased food production dramatically through the use of hybrid plant, fertilization, and irrigation. The world still has an ever expanding population, climate change poses a new threat to agriculture. The threat of famine has not gone away.
Science is looking for another green revolution. And this might actually be happening in San Diego. Scientists at the sidewalk institute have mapped the genome of a mustard weed providing the world with a model for creating plants that are productive, disease and drought resistant of the joining me to talk about this is doctor John Ecker. Doctor Ecker is a professor of biology at the Salk institute. The Salk's biology program has just received a top ranking from. Thompson Roiters. And thank you for coming in.
ECKER: Thanks, Tom. It's Joe.
FUDGE: I'm sorry. Joe. If that's your name, that's what I'll call you. First of all, talk with me about this challenge of feeding the world. What stands in our way? And what do you consider to be the biggest challenge?
ECKER: There are many challenges with growing crops throughout the world, with, are as you mentioned already, a changing climate. Along with changing climate, you have changes in pest populations that go look along with that. So there are lots of challenges related to being able to produce plants that are resistance to pathogens, and for example, are drought resistant. So there are many stresses on the plants that are of biotic and abiotic --
FUDGE: Talk a little bit more about the challenges that we're seeing out here. We're talking about drought, disease, of course disease has always been a problem with plants. But what would you consider your top priorities in terms of creating plants that can feed the world?
ECKER: Well, I think there are many avenues. Our own institute is interested in creating the tools that others can use to study plants. We have our own biological interests in plant growth and hormone response, and response to light. But the challenge will be to translate this basic knowledge into field crops. And that's largely the focus of companies. Like a drug being produced in academia would be very challenging, but you need pharmaceutical companies. So the information we produce in terms of basic research and understanding of plant growth and development gets handed off to industry to create those plants.
FUDGE: So eventually industry has got to make it happen.
FUDGE: Tell us about this plant whose genome you mapped. How did you get so curious about a mustard weed?
ECKER: Right. So this is the little weed that could, I like to say. It's Arabidopsis Thaliana. The genome of this plant was actually sequenced, and that's a kind of map of all of the jeans in the year 2000. And our group is part of that. The most recent map that we recently published in two papers in science magazine a few months ago, has to do with how proteins talk to one another, it's a map of a cellular network. And that helps us to begin to understand what the proteins do, is the next step. 50 we understood what the jeans do, now we're hoping to understand what the proteins do.
FUDGE: We're talking about feeding the world, which is a very important thing and quite a challenge in a time of climate change. Call us if you would like at 1-888-895-5727. My guest is Joe Ecker, professor of plant biology at the Salk institute. So finding out what proteins do, finding out what jeans do, and I assume that what you would eventually do with this information or what people would do with this information is manipulate those genetics in order to create a new kind of plant.
ECKER: There are a number of ways the information can be used. One is to basically understand how much variation there is in natural populations. In other words, if you go and find varieties of.
Arabidopsis from around the world, they'll grow from anywhere from the arctic circle down off the coast of Africa on cape Verdi island. And understanding how that's possible by looking at their DNA and looking at the proteins will allow us to identify what jeans can be important in those processes. And so by understanding the natural variation that occurs, we can use that for example for breeding purposes or for genetically modifying plants to be able to adapt to new environments.
FUDGE: Getting back to the mustard weed, why is it so important to have the genome of this mustard weed mapped? I talked to some other people at the Salk institute, and they have compared this weed to a lab rat or mouse. Can you run with that?
ECKER: That's right. It's equivalent to what people would use in animal biology as a mouse model or a -- for drosophila, for example. A fruit fly model. This is a reference organism. We're trying to build all different kinds of reference maps of this weed. . It grow it is fast, it has a small amount of DNA in its cells. We're able to add DNA or make mutations in this plant very easily. So we have mutations in most genes in the genome. And that's unique among the plant world. That allows us to make hypotheses, very large numbers of hypotheses very quickly.
FUDGE: Using this mustard weed. But you're not trying to turn this mustard weed into the next great corn plant.
ECKER: No we're not. We're trying to understand how jeans function in Arabidopsis. And we know there's a lot of conservation of function. You mentioned, for example, the green revolution. The gene that was bred by Norman Borlag into wheat that caused it to dwarf, and dwarfing is important in increasing the yield of the plant, because of instead of putting its energy into growing tall, it puts its in energy into producing more seeds. The gene that was important in doing that exists in.
Arabidopsis, so that tells us something important about how to breed other plants like that. And what other jeans in.
Arabidopsis do can be translated into other plants.
FUDGE: And this is something that Mr. Borlag wouldn't know because he didn't know the genetics.
ECKER: Absolutely. He didn't know the molecular basis. He knew the type, what the plant looked like, and he bred for that. Now we know what the jeans are, for example, for that particular trait, and men other traits. And these can be selected for by molecular braiding, that is looking for strains that have that. Or you request introduce into the plant that doesn't have a particular type like drought resistance, you can create that trait.
FUDGE: We have a call from Nan in Kearny Mesa. Go ahead, you're on with Joe Ecker.
NEW SPEAKER: Hi Tom, it's Nan Sterman.
FUDGE: Oh, hello, nan. Man is a master gardener, in case listeners don't know.
NEW SPEAKER: I am a horticulturalist, and as a plant biologist too. The research that's going on, I think it's really important. I have this little nagging concern because when you go from bench research to applied situations, one of the issues that still needs to be considered is whether the plant can be controlled in an agricultural situation or whether because it's so successful it succeeds better than we expect, and it becomes invasive and then causes problems by our competing native plants and habitat. So I'm wondering if there's any thought to that, how you would make sure plants don't become invasive or is that at the next level?
ECKER: That's an interesting and important concern. Obviously there some examples of introducing plants, foreign plants that will take over. I think the kind of traits that we're talking about here are fairly simple, and the sort of first generation, like improving root architecture so that plants can take up more water would be an important concern for increasing the plant's ability to resist drought. And a few other simple traits, I think the traits of invasiveness are fairly complicated and not single gene events, it's an important concern, and those kinds of tests need to be done when introducing a new variety.
FUDGE: So is that something that you can control? The invasiveness of a plant? Because if you're creating a plant that's healthier than most, I guess I can imagine how that could be a problem.
ECKER: We're really talking about modern agriculture where you have hundreds and thousands of acres of one variety of plant. For example a maze plant. And it wouldn't be particularly invasive to introduce a gene into a maze plant that would allow it to be more resistant to a pest because it's an annual plant that's harvested every year.
FUDGE: Thank you very much for calling in. There's an expression I'm almost afraid to use, but I'll use it now. Genetic engineering. A lot of people when they hear that they think that that's a bad thing to do to nature. What do you tell folks about this? How do you tell them that, no, manipulating the genetics of I plant is not necessarily a bad thing?
ECKER: Well, you have to understand that plant genomes are manipulated every day. And what I mean by that is if you go out and compare two varieties of any plant species, let's say corn, to inbred varieties are 25% different from one another. That's an enormous amount of change in the genome. And a lot of that difference is due to mobile DNA. DNA jumping around in the genome. And so that's millions of bases that are different in one plant versus another. And yet these are both maze. So you have to understand something about the natural world to be able to on understand concerns about genetic modification. And I think people don't appreciate how much upon variability there are in genomes in plants.
FUDGE: So what is the difference between what you're doing and what farmers have been doing for a long time when they created hybrid plants?
ECKER: So they're -- what we're doing is trying to study how plant jeans functions. Will and we do that by creating mutations. We will alter jeans, and then and what the function of those genes are. In terms of modification, what companies will do is take one of the genes where we know what its function is, for example, increased resistance of a particular pest, and they'll introduce that from the plant that's resistant, where they identified to the plant that's susceptible, so that it becomes resistant. Instead of introducing thousands of genes by trying to breed the resistance from the plant into the new plant, you're more sort of like laser surgery, taking one gene, and it without all the baggage of the other genes that have negative effects. I think it's a much more precise technology. And we're just beginning to see the fruits of that.
FUDGE: Joe Ecker is a professor of biology at the Salk Institute. We're talking about the efforts of the Salk institute and him and other scientists to create new foods to feed the world. Can you give us an example how this kind of science has led to the creation of a new plant which has helped to feed starving people in India or in Africa?
ECKER: Yes. So the first generation of plants that have been provided by taking information, basic information, and then using that, really were more for the farmer to allow the farmers to grow plants that were more resistant to pathogens or would be resistant to herbicides. The next generation that we'd see coming are plants that have increased yield properties, increased drought resistance, and stress resistance. So those are really the direct benefit of studying the little weed that could. Because the genes that were using used to understand those processes came arabidopsis.
FUDGE: Do we need another green revolution?
ECKER: Absolutely. If you just read the paper and see what's going on in the world, either massive floods that happened last year in Pakistan, and droughts in Somalia. These have devastated the agriculture there. We're going to need to understand more about how plants grow and develop in changing environments to be able to allow enough food to feed the world. There's a lot of pressures on feed security, biofuels was one, for example. We saw an impact of that a few years ago. So we really need to be worried about food security because it's a sort of something that we haven't really thought about until the last decade.
FUDGE: Well, once again, doctor Joe Ecker is a professor of plant biology at the Salk institute. The Salk's plant biology program just received the top ranking from Thompson Roiters. And Joe, thank you very much for coming in.
ECKER: Thank you very much, Tom.