If you were talking to Douglas Anthony Cooper from Huff. He too is a bully, who is very verbally abusive to others who do not agree with his point of few. Many people here pointing fingers here at PETA, eat animals. 99% of cruelty to animals happens to the animal they eat.
it was interesting to read your (unsubstantiated) account and i certainly respect your opinion, but like most things i read on the internet- i read with a weathered eye toward accuracy, trustworthiness and verifiability.
FinePrint 10.05 With Full Crack Here
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Peta is in the building please go back to your kennels and stay there with you dogs, if you only have one please stay in the ring you are showing in, as soon as this is resolved the show will continue!!! its something I will never forget.
Anyway, thank you for writing this timely blog. Going to go read the follow-up interview now. Oh, and no matter where you are, remember that these people a chemically imbalanced, disconnected from empathy and have no problem with murder.Head-on-a-swivel! Be safe.
I too am a field worker for Peta and you are full of SHIT!!! When we see a bad situation for a dog we call local authorities to deal with situation appropriately. Never once have I been instructed to take a dog and bring it in for Euthanasia . According to you you do not even live in the US I did report this to headquarters they had already seen it . Enjoy lying to naive people . Maybe Rick Berman will put you on his payroll or are you already
I think this post would be more honest if it admitted there is no feasible way for PETA to significantly increase animal adoption in the Hampton Roads area, which is well served by a number of large (and full) shelters, including the Norfolk and (excellent) Virginia Beach facilities. Opening their own shelter would cost millions (probably much more than is budgeted for all local casework) and would fill up with animals in a few weeks. Then where Black Boy, or the thousands of other animals like him, be placed in the following weeks, months, and years? They would be left freezing to death under porches or sick with untreated heartworm or bred for fighting dogs.
Trying to get them to do something in the town where I first started my rescue was a joke. I took pictures of a dog in a pickup on a hot day. Windows barely cracked. SO once the cops wouldnt do anything i put the picture on facebook. Still heard from the people thinking I was being judgemental and how dogs love to go for rides.. UM OK>so I think Common sense is gone. I just think it is one thing after another that people are so selfish on. Breeding , treatment, and worried about spending money on their pets. I really hope this is fixed soon. I doubt it will be a over night fix but animals deserve so much better
I think most people reading this are aware that PETA is an animal rights group, many might not be aware that CAP the an animal rescue/welfare division of PETA. This is not a piece of journalism, it is my blog and I have never said otherwise. Therefore, I am not obligated to report both sides of a story, I am only obligated to write about my experiences honestly, which I have done. I have also encouraged people, many times, to do their own research and come to their own conclusions. What anyone does with my story is up to them.
00:00:08.10I'm Elliot Meyerowitz.00:00:10.04I'm at the California Institute of Technology,00:00:13.12on the faculty00:00:16.08in the division of Biology and Biological Engineering.00:00:18.15What I want to talk about,00:00:21.18in three parts,00:00:23.09is why we use plants in the laboratory,00:00:27.04how we use the plants,00:00:29.08and one set of things that we've learned from the plants00:00:31.29that we learned for reasons of curiosity,00:00:34.18but which may have implications00:00:36.26for agriculture in the future.00:00:39.02In this part, Part 1,00:00:41.06I'm going to talk about the urgent need we have00:00:44.15for learning more about plants,00:00:47.08for a variety of reasons00:00:50.00that have to do with human progress00:00:52.02and human suffering,00:00:54.00and I'm going to talk about a set of methods00:00:56.06that we've developed for studying plants00:00:58.21so that we can learn, in detail,00:01:00.26how they grow and develop.00:01:03.16And I'm also going to say a couple of things00:01:05.24about why that's important practically,00:01:08.18as well as to satisfy our curiosity.00:01:11.21In Part 2,00:01:13.16I'll then talk about the application of these methods,00:01:16.10in our laboratory,00:01:18.20to understand more00:01:21.20about how the leaves and flowers of a plant00:01:24.05are organized around its stem,00:01:26.06what you can see in the pictures here.00:01:28.26And in Part 3,00:01:30.23I'll talk about some surprising aspects00:01:32.24of the models we've developed00:01:34.24for figuring out how it is00:01:37.06that leaves and flowers arrange themselves00:01:39.08around a stem00:01:41.04that has led to a new way of looking at plant development,00:01:43.16in which mechanical signaling00:01:45.20is as important as chemical signaling00:01:47.29in the communication from one cell to the other00:01:50.16and the formation of developmental patterns.00:01:53.06So, we'll always be talking about the formation00:01:55.29of developmental patterns,00:01:57.17but with a long preface,00:01:59.15which is Part 1.00:02:01.15Why should we study plants?00:02:03.16And that's what I'll start with,00:02:05.13and then we'll get up to,00:02:07.02how do plants use chemical signals00:02:09.00to form developmental patterns?00:02:12.04And in Part 2,00:02:13.24we'll actually answer that question, in part,00:02:16.10how do plants use chemical signals?00:02:18.08In Part 3, we'll talk about physical signals.00:02:22.06This is a map00:02:25.06from the World Food Organization,00:02:27.02which shows hunger in the world.00:02:29.04The darker areas, here,00:02:31.10in Africa and in Southeast Asia, back here,00:02:34.16are places where people don't have enough to eat.00:02:38.03Not enough calories and not enough of other nutrients,00:02:40.03and if you can read the fine print on this map00:02:43.10you'll see that it says that more people00:02:45.13die of hunger every year00:02:47.10than from AIDS, from Malaria,00:02:51.06and Tuberculosis, combined.00:02:53.02So, one problem that we have00:02:55.16that relates to the study of plants00:02:57.24is how to feed the world.00:02:59.11Let's look at the numbers.00:03:01.08According to the Food and Agriculture Organization00:03:03.02of the United Nations,00:03:05.27805 million people suffer from chronic hunger,00:03:09.20and this is the report of 2014.00:03:12.16That's at an encouraging low level00:03:15.21compared to some years in the past,00:03:17.10but it's still almost one in eight people on Earth00:03:20.02who don't have enough to eat.00:03:22.04One in four children in the world00:03:25.08are stunted by malnutrition.00:03:28.06In the United States,00:03:29.24we're not really familiar with the extent of hunger00:03:31.26in the world,00:03:33.23but it's serious.00:03:35.08Poor nutrition, according to the World Food Program,00:03:37.28causes nearly half of deaths in children00:03:40.21under five years old.00:03:42.15That's 3.1 million children each year.00:03:46.15That's a remarkable number.00:03:51.14And so here's the World Health Organization's00:03:54.12conclusion on the same subject.00:03:56.20Together, maternal and child undernutrition00:03:59.28account for more than 10 percent00:04:02.08of the global burden of disease.00:04:04.14So, in a series of films00:04:06.12that are largely medicine00:04:08.07and the treatment of individual diseases,00:04:10.05there's a good region to have talks about plants,00:04:13.07such as this one,00:04:14.26because 10 percent of all the disease in the world00:04:17.17is caused by our inability to grow plants00:04:20.07in the right places at the right times00:04:22.09and the right amounts.00:04:24.22And an enormous contribution00:04:27.08to the health of people in the world00:04:30.01would come from a better understanding of how to grow plants,00:04:32.18and of how plants grow.00:04:35.06It's surprising, in fact,00:04:37.04that so little attention is paid to this part of biology00:04:39.18in our medical funding agencies.00:04:42.26Now, why are plants so important?00:04:45.10I don't have to tell you that it's because they're what we eat.00:04:48.10Plants directly provide00:04:51.06about 85% of human food.00:04:53.29And that other 15% is almost entirely00:04:57.05something like this buffalo, that just ate a plant.00:05:00.01That is, in the richer societies00:05:02.04where we eat meat,00:05:03.27we couldn't have meat either,00:05:05.16unless there were plants growing,00:05:07.05so that our food comes from plants.00:05:09.23Now, right now, as we pointed out,00:05:11.25805 million people on Earth00:05:14.07are not getting enough to eat in the past year.00:05:17.29There are about 7.8 billion people on the Earth.00:05:22.25So, the problem is bad,00:05:24.21and it's about to get worse,00:05:26.27because by 2040 there will be 9 billion people in the world,00:05:29.19as you can see on this graph.00:05:32.19That's almost 25% more00:05:34.29than the number of people that we have on Earth now.00:05:37.15And we have to learn to feed all of those people,00:05:40.00not just the 805 million who were starving,00:05:42.16but the additional 1.2 billion00:05:45.00who will be added to the world's population00:05:47.20by 2040,00:05:49.01which is not very many years from now.00:05:52.10Now, you might think that it would be easy to do this,00:05:55.00we just expand the amount of agricultural land00:05:58.05that's used by farmers00:06:01.01so that we can grow more food,00:06:02.27but in fact this isn't happening.00:06:04.18All the agricultural land that's suitable for plant growth now00:06:08.03is in use.00:06:09.25Indeed, the amount of agricultural land00:06:12.25that's used on Earth is slowly going down.00:06:17.03Why?00:06:18.15Because there's desertification00:06:20.21in some parts of the world,00:06:22.03where current agricultural land is being degraded00:06:23.27to the point where it becomes desert.00:06:26.10And there's urbanization00:06:28.12in some of richest farming areas in the world,00:06:30.11such as around Shanghai, in China,00:06:32.15the expansion of the city00:06:34.23is eating up the farmland.00:06:36.02So, we can't simply expand the amount of land00:06:37.23on which we grow the food.00:06:39.17In fact, we have to face not only an increasing population,00:06:42.01but a slowly declining amount of arable land00:06:44.29that can be used for agriculture.00:06:48.15There's another problem00:06:50.13that's also going to make things worse,00:06:52.01and this is climate change.00:06:53.19We know that the climate is warming,00:06:56.12and the growth of our crop plants00:06:58.10depends very strongly on the ambient temperature.00:07:01.15This is just one graph from many studies,00:07:04.22which shows that the change in the yield for each degree warming00:07:10.09can be very serious.00:07:12.01In drought management,00:07:14.09that is in dry years,00:07:15.25we could lose 40% of our crops00:07:19.01with just a change from 22 to 24 or 26 degrees Centigrade.00:07:24.172 or 3 degrees Centigrade,00:07:26.28an increase in temperature that we have to expect,00:07:29.17given the level of carbon dioxide in the atmosphere,00:07:32.03so that we're...00:07:34.20have people who are starving now,00:07:37.11we'll have more people to feed in the future,00:07:39.11we'll have less land with which to feed them,00:07:42.09and the warming of the climate00:07:45.11will reduce the yields on the land that we do have.00:07:47.18And so we have a daunting set of challenges00:07:49.24to grow enough food to feed the world in the future.00:07:53.16There are other reasons we would want to learn00:07:56.01more about how plants grow.00:07:58.25We've mentioned climate change00:08:01.05and the increasing carbon dioxide in the atmosphere.00:08:04.18Plants take up the carbon dioxide in the atmosphere00:08:08.12and replace it with oxygen,00:08:10.13as part of their photosynthesis.00:08:12.19In fact, plants take up a net of00:08:15.1460 billion tons of carbon each year00:08:17.24via photosynthesis,00:08:20.05and the burning of fossil fuels,00:08:22.03the anthropogenic contribution to global warming,00:08:24.21adds 9 billions tons.00:08:27.05And so the plants are capable00:08:29.13of taking out far more carbon dioxide00:08:31.09from the atmosphere00:08:32.27than we humans put in in excess00:08:34.23of what happens from normal, natural processes.00:08:38.05The carbon in plant biomass on land00:08:41.06is about 550 billion tons.00:08:44.15The entire atmosphere00:08:46.28holds 800 billion tons to carbon00:08:49.06as carbon dioxide,00:08:51.20so the plants play a major role00:08:54.15in carbon balance in the atmosphere,00:08:56.23and they can play it either way.00:08:58.11If we can encourage plants to photosynthesize more,00:09:00.21or grow more plants on the land that we have,00:09:03.23they'll take up net carbon00:09:06.03and help up to reduce the effects00:09:08.10of the excess carbon that the burning of fossil fuels causes.00:09:11.27If, on the other hand,00:09:14.06we denude the land of plants00:09:16.13and the carbon that's stored in the wood00:09:18.25and other parts of those plants00:09:20.26is released back to the atmosphere,00:09:22.22we'll exacerbate the problems that we're causing00:09:25.03by burning fossil fuels.00:09:27.23And so plants play a major role in the carbon cycle,00:09:31.05and to mollify the effects of human activities00:09:36.18on the carbon cycle00:09:38.11we also have to learn more about plants.00:09:41.07So, what do we need?00:09:42.13We need a better understanding00:09:44.26of how plants grow,00:09:46.11a better understanding of how plants00:09:48.13interact with their environments,00:09:50.00including the abiotic environment,00:09:51.25that is, the non-living environment00:09:54.09of light, temperature, water,00:09:56.09and nutrients like nitrogen and phosphorous,00:09:58.13which are the two that are most often00:10:00.29lacking in agricultural land,00:10:02.23and we also have to learn how plants interact00:10:04.23with the biotic environment,00:10:06.11the pathogens that kill the crops00:10:08.12while they're growing in the fields,00:10:09.29or that destroy the yield after the harvest.00:10:13.21I'm going to be talking00:10:16.21about a developmental aspect of plants,00:10:19.07the position of which the leaves and flowers are found,00:10:22.00which has to do with the abiotic environment,00:10:24.00and I hope there will be other lectures in this series00:10:26.15on the interactions of plants with pathogens00:10:28.29and with the biotic environment.00:10:32.09So, what is it that we don't know00:10:34.00that we need to know,00:10:35.18to be able to understand00:10:37.24how the plants genome00:10:40.19turns into the living, 3-dimensional plant?00:10:43.02We don't know how the genetic information of the plant00:10:45.09becomes a plant,00:10:47.14and so we can't predictively model plant growth00:10:50.07and changes in plant growth00:10:51.21that occur in response to changes in the genome,00:10:54.15or in changes in the environment.00:10:57.07We can't predict the effects of genetic changes,00:10:59.24and so we can't breed plants for plant size,00:11:02.07for plant architecture,00:11:04.13for growth rate, or yield.00:11:06.22We can only plant plants00:11:08.15and look at random for ones that seem better,00:11:10.19which is a laborious and very time-consuming process.00:11:14.09Let's make an analogy00:11:16.25to a product of human industry00:11:19.03that gives us a direction00:11:21.12that we might be able to begin taking00:11:23.09to better understand how plants grow.00:11:25.23A Boeing 777 aircraft,00:11:28.19which was designed in the early 1990s,00:11:31.10and was one of the first airplanes00:11:33.12to be designed entirely in computers,00:11:36.21has about 130,000 different types of parts,00:11:40.18and given that some of these parts00:11:42.24are found in greater numbers than one,00:11:44.223,000,000 total parts.00:11:47.19That degree of complexity00:11:51.05could be encompassed in computer-aided design programs00:11:55.08and in the computers that existed 20 years ago.00:11:58.22Now, a plant cell is not00:12:01.23of much greater complexity00:12:03.15in terms of its part numbers00:12:05.15than a 777 aircraft.00:12:07.20There are 27,000 different types of proteins00:12:10.29that are found in all the cells00:12:13.04of the plant together,00:12:14.13each individual cell has some smaller number,00:12:16.20and perhaps 10,000,000 protein molecules00:12:22.27of these 27,000 different types.00:12:25.26So, to have a computer model00:12:28.24of all the proteins of a plant cell,00:12:31.27and of all the different types of proteins of a plant cell,00:12:34.17is something that would have been possible00:12:36.22with the computers that we had 20 years ago,00:12:39.03and easily possible with the types of computers00:12:41.01that we have today.00:12:43.12Now, this analogy00:12:45.03between airplanes and plants isn't exact.00:12:47.09Plant cell proteins move and interact00:12:49.15with different partners,00:12:51.08at speeds so that they have different partners00:12:53.27every few milliseconds,00:12:55.17while the parts of an airplane00:12:57.09don't move with respect to each other,00:12:59.07except for the control knobs and dials,00:13:01.28and if they do move it's a very bad thing.00:13:04.09A plant cell has at least equal complexity,00:13:08.08in terms of part numbers,00:13:10.14as a 777 aircraft,00:13:11.29but in linear dimension00:13:13.19it's 10^7 times smaller,00:13:15.09so more than 10^20 times smaller00:13:17.27in volume.00:13:19.13So, it's a nanopackage that contains the complexity00:13:21.13of an airplane.00:13:23.01And a plant cell can reproduce itself,00:13:24.15which an airplane can't,00:13:25.27it has to be made in a factory.00:13:27.15And a plant cell can make its own fuel00:13:29.08through photosynthesis,00:13:30.23which an airplane can't do.00:13:32.10So, there's some principles of construction00:13:34.09that a plant cell has00:13:35.26that an airplane doesn't have,00:13:37.06but nonetheless the computer technology00:13:39.04of 20 years ago00:13:41.02was enough to encompass all the parts00:13:42.28of something as complicated as a plant cell,00:13:45.27though not something as dynamic as a plant cell.00:13:48.17Computers of today00:13:51.19are up to the task of a full understanding00:13:53.21and description00:13:55.07of how a plant cell works.00:13:57.07So, we have a possibility00:13:59.01to develop a new approach to the study of plants,00:14:01.05one that we call, half jokingly,00:14:03.10computational morphodynamics,00:14:06.18in which we access the developmental information00:14:10.01of a plant in a dynamic way00:14:12.15by making real-time movies00:14:14.07on a cell by cell basis00:14:16.19of what each cell is doing00:14:18.10in terms of its expansion and its division,00:14:20.10what each gene is doing00:14:21.29in terms of its expression pattern,00:14:23.19and what each protein is doing00:14:25.10in terms of its movement within the cells.00:14:28.19Our computers can handle that information00:14:31.05and we've developed microscope methods00:14:33.06that enable to access that information,00:14:36.00and if we put that into the biological equivalent00:14:39.20of a computer-aided design program,00:14:41.15then we have a beginning of a complete definition00:14:44.00of the developmental program of a living plant.00:14:48.14The example that we're going to take00:14:50.12is the example of phyllotaxis,00:14:52.12the pattern of leaves and flowers00:14:54.18around a stem in a living plant.00:14:56.16Why are we going to take that example?00:14:59.08Because the pattern of the leaves00:15:01.24determines the photosynthetic efficiency00:15:03.24and therefore the yield in a crop plant,00:15:05.29and also because the phyllotactic pattern00:15:08.09is simply fundamentally interesting,00:15:10.19to understand how it is00:15:12.26that something like a pineapple or a pinecone or a sunflower00:15:16.03can have that lovely pattern of organs,00:15:17.29forming one after the other around its stem.00:15:21.18How does something as stupid as a plant00:15:23.14measure an angle one time after the other00:15:25.24to make a spiral phyllotaxis00:15:27.18in which each subsequent organ00:15:29.12comes out about 130 or 140 degrees00:15:31.29from the previous organ,00:15:33.16one time after the other after the other,00:15:36.11to make this spiral phyllotactic pattern.00:15:38.23So, the practical aspect:00:15:41.14canopy structure depends on phyllotactic pattern,00:15:45.00and therefore the photosynthesis00:15:46.26that can we done by a field of plants00:15:48.17depends on the position00:15:50.17at which the leaves are found,00:15:52.27and that models of soybean growth,00:15:55.00for example,00:15:57.09in which different positions of the leaves,00:15:59.15angles of the leaves,00:16:01.03and reflectivity of the leaves are put in,00:16:02.23show that if we could change00:16:05.02those qualities of a soybean plant,00:16:06.25we could predictively create00:16:09.198.5% more productivity in a field of soybeans,00:16:13.13and at the same time00:16:15.25use 13% less water.00:16:17.15So... that what we understand now00:16:20.12about the growth of soybeans00:16:22.18tells us that if we could change their development00:16:24.19to change the pattern of leaves around the stem,00:16:27.05we could increase the yields of soybeans00:16:29.16and consequently feed people.00:16:31.29So, there's a practical aspect00:16:34.02to the phyllotactic question,00:16:36.11but there's also a theoretical aspect00:16:38.13that's been of interest to mathematicians00:16:40.11and to mathematically-minded biologists00:16:42.05for a long time.00:16:44.13How does something as dumb as a plant00:16:46.15measure an angle of 130 to 140 degrees00:16:49.27around its stem over and over again?00:16:51.19They don't have protractors.00:16:53.19The first description of phyllotaxis00:16:55.21was the ancient Greeks.00:16:57.27Theophrastus described it in this book00:17:01.14that you can't read,00:17:03.05but there's the title page, "Historia Plantarum".00:17:06.03The word phyllotaxis originated00:17:08.20from the 18th century, Charles Bonnet,00:17:10.28who felt that by categorizing the phyllotactic patterns,00:17:14.11the different phyllotactic patterns of plants,00:17:16.22you could come to some sort of natural classification of plants,00:17:19.14which turned out to be wrong.00:17:21.19The first mathematical considerations00:17:24.21and mechanistic model,00:17:27.05the first causal model for phyllotaxis,00:17:29.13was done by a great 19th century botanist00:17:32.11named Hofmeister,00:17:34.05whose picture I've shown there.00:17:35.26And Hofmeister created a model00:17:40.10for how a plant might generate that organ00:17:43.14time and time again00:17:45.07for the formation of new leaves and new flowers.00:17:47.14Not a model that we'll discuss,00:17:49.09because it no longer pertains.00:17:51.15There were many experiments done on phyllotaxis,00:17:53.21and we'll come back to the some of them in the 1930s00:17:56.09by Robin and Mary Snow,00:17:58.11and in the 1950s by Ian Sussex,00:18:01.08and these experiments will come back later00:18:03.23in this collection of talks,00:18:05.17because the observations that they made00:18:07.21form the basis for the computational models00:18:09.18that I'll describe.00:18:11.17Phyllotaxis has also been of great interest00:18:13.26to mathematical biologists00:18:16.00and to mathematicians00:18:17.22because they're interested in the natural origins00:18:20.14of patterns like this spiral phyllotactic pattern,00:18:23.07and one that I'll point out is Alan Turing,00:18:26.03about whom there's been a recent popular movie,00:18:28.15as he was one of the British mathematicians00:18:30.21who decoded the German secret codes00:18:34.01during World War II,00:18:36.03was working at the time of his death00:18:37.27on trying to come to a mathematical solution00:18:40.06to how it is that plants00:18:42.20create phyllotactic pattern,00:18:45.05and we'll come back to his model00:18:46.29in Part 2 and in Part 3.00:18:49.14So, we have an urgent need00:18:51.21to understand how plants grow and develop00:18:53.29because humans are starving,00:18:55.26and more humans will starve00:18:57.23if we don't figure it out.00:18:59.15We have one possible mechanism00:19:01.14by which we can learn enough about plants00:19:03.06to change the way they grow00:19:05.00in a predictive and design-oriented way,00:19:07.21which is computational morphodynamics,00:19:10.16and I've interested the problem,00:19:12.21one small aspect of plant growth,00:19:14.18that's of some relevance to agriculture,00:19:17.09that we will explore by using computational models00:19:20.04and dynamic acquisition of information00:19:23.08from the growing plants themselves.00:19:25.10So, how do we study, understand,00:19:28.12and learn to change the phyllotactic pattern?00:19:30.23We take the problem to the laboratory,00:19:32.23and in the laboratory00:19:34.27we are using a plant00:19:36.17that's called Arabidopsis thaliana.00:19:38.16It's a member of the mustard family00:19:40.15and although this is a small plant,00:19:42.06that's a normally-sized hand,00:19:45.23and one of the reasons that we use it in the laboratory00:19:48.27is just because of it's of small size,00:19:50.29so that even in a moderately sized laboratory like mine,00:19:53.06we can grow something like a million plants a year,00:19:57.11and that's very important for doing a lot of genetic experiments.00:20:00.18It has other properties.00:20:02.16The small size I've mentioned...00:20:04.23it has a rapid lifecycle.00:20:06.05You can grow the plant from seed to seed00:20:08.09in about 8 weeks,00:20:10.05and so the sorts of genetic experiments00:20:11.23that we'll be discussing00:20:13.08can be done with great facility using this plant,00:20:15.07while with the more traditional crop plants00:20:18.26there's one or two generations a year,00:20:20.19and so the same amount of work00:20:22.15takes a very much longer period of time to do.00:20:25.08It grows very easily.00:20:26.27It's a little weed that grows00:20:28.28mostly throughout Europe and western Asia,00:20:30.27also in parts of eastern Asia.00:20:33.18It grows well under lights at room temperature.00:20:36.29You can get about 20,000 seeds per plant;00:20:39.23they're very fecund.00:20:41.09And as of the year 2000,00:20:42.29the genome was completely sequenced,00:20:45.05so we know what the amino acid sequence00:20:48.11of all of the proteins coded in the genome are,00:20:51.13what all the small RNAs coded in the genome are,00:20:53.21and we know their relatives positions00:20:56.01to each other in the genome.00:20:57.04So, we have an enormous amount of genetic information00:20:59.18about this plant,00:21:01.25and so it serves as a model system00:21:04.06for a very large number of laboratories00:21:06.22that study plant growth and development.00:21:09.21And then, what do we do with Arabidopsis00:21:12.08to find out how the phyllotactic pattern occurs,00:21:15.09and therefore how we can change it in a predictive way?00:21:18.06We find a way to watch the phyllotactic pattern00:21:21.08happen as the cells divide,00:21:22.25as the cells grow,00:21:24.18and create the new position00:21:26.12for each leaf and for each flower.00:21:28.01So, we look at the shoot apical meristem,00:21:30.17which is where the action is,00:21:32.03the collection of cells at the end of every shoot00:21:34.23that's creating the primordia00:21:37.03for leaves and flowers,00:21:38.17and pouring out behind it00:21:41.13the cells that will become the stem,00:21:43.01so that the shoot apical meristem is a collection of stem cells,00:21:45.19both literally and in the sense that00:21:49.03the cells provide for differentiated cells00:21:51.05in the mature organism.00:21:52.27It forms during embryogenesis in the plant00:21:55.18and it persists through the life of a shoot,00:21:57.23pouring out behind it the cells00:22:00.07that make the stem00:22:01.26and on its sides00:22:03.29the cells that will make leaves and flowers.00:22:05.20How, you may ask,00:22:07.21does this go on forever? It doesn't.00:22:09.25Once the shoot stops growing it's already made some leaves,00:22:12.15and in the base of each leaf00:22:14.17a new meristem forms00:22:16.09and that makes a branch,00:22:17.22so that one step after the other00:22:19.17the meristem, the primary embryonic meristem,00:22:21.25creates a primary shoot,00:22:23.17then there's secondary shoots, tertiary shoots...00:22:26.15until you have the whole oak tree,00:22:28.08all coming from the activity of a single shoot apical meristem00:22:31.15and its progeny00:22:33.27over long periods of time.00:22:35.23So, we take the shoot apical meristem,00:22:37.16where the phyllotactic action is happening,00:22:39.23and we developed a series of microscope methods00:22:41.25so that we could look at them in real-time00:22:43.10and see what's actually happening00:22:45.04as each organ forms,00:22:46.18look at the patterns of gene expression,00:22:48.09at the places in the cells00:22:50.04where the proteins are found,00:22:51.26how the cells divide,00:22:53.11and what directions they expand before they divide,00:22:56.07and then we created a set of computational image processing methods00:22:59.27that enable us to put into our computers00:23:04.08all these activities of the plants00:23:06.13and then apply our models00:23:08.25to the computer models in silico.00:23:10.20So, we developed methods to watch gene action00:23:12.27in these live images.00:23:14.10This is a shoot apical meristem of an Arabidopsis plant00:23:17.11at a time when it's making flowers.00:23:19.27The plant here is...00:23:22.04this is the shoot apical meristem in the middle.00:23:23.24Each of these cells00:23:26.01is about five micrometers across,00:23:28.02very small,00:23:30.00and those cells all look the same as each other00:23:32.03in the shoot apical meristem,00:23:33.18and then surrounding it we have flowers.00:23:35.14So, here's a young flower00:23:37.10that's forming on the flanks of the shoot apical meristem,00:23:39.06there's an even younger flower00:23:41.22right there that's just beginning to form,00:23:43.16and here's one of the older flowers00:23:45.26that's already beginning to make its sepals.00:23:48.26So, one after the other,00:23:50.20the flowers are made around the meristem00:23:52.07at this angle of about 130 to 140 degrees,00:23:54.25and we want to know how the plant chooses the angle.00:23:57.22Let me give you an idea of what00:24:00.09a lovely nanomachine this is.00:24:02.23this is a photograph of a thread00:24:04.27going through the eye of a needle,00:24:07.00and this little tiny thing up in the corner00:24:09.20is an Arabidopsis shoot apical meristem at the same scale.00:24:13.00You can pack dozens of these00:24:15.14through the eye of a needle,00:24:17.02and yet those meristems00:24:19.03will make the whole Arabidopsis plant,00:24:20.20and very similar meristems,00:24:22.12ones that aren't much bigger,00:24:23.28will make an entire oak tree or a redwood tree00:24:26.00if you just let the cells keep dividing long enough.00:24:28.07And if we could understand that00:24:30.01we could understand how the genome of a plant00:24:31.28translates into00:24:35.06the above-ground architecture of a plant00:24:36.28and all its parts and all its functions.00:24:39.13Here's a view of the phyllotactic pattern of Arabidopsis00:24:42.02as it forms.00:24:45.11On the left side, it's making leaves00:24:47.10and they're numbered from oldest to younger,00:24:49.14and on the right side the shoot apical meristem00:24:51.21is making flowers,00:24:53.18later in the life of a different plant,00:24:55.15since to take these scanning electron micrographs00:24:57.09we had to kill the plants.00:25:00.07So, the pattern is quite regular00:25:01.28and occurs in the leaves and the flowers.00:25:04.14Now, the methods we developed for finding out what's going on00:25:08.13as the phyllotactic pattern forms00:25:10.19are live imaging methods00:25:12.16in which we make parts of the plant fluorescent,00:25:14.10either gene products as proteins,00:25:16.05or parts of the cells,00:25:18.00as in this case where we're looking00:25:21.11at the plasma membranes of the individual cells,00:25:23.03and we use a laser scanning confocal microscope00:25:25.25to access full 3-dimensional information00:25:28.05from the top of the plant,00:25:29.23which we've computationally00:25:31.25projected forward in this image00:25:33.24and then stitched together00:25:36.00one observation after the other00:25:37.21that were made every two and a half hours00:25:39.23for several days00:25:41.19in an athletic event of considerable difficulty00:25:45.05by a former postdoc, Venu Reddy.00:25:48.21And you can see the division of every single cell00:25:52.05occurring on the surface of the plant here,00:25:53.28and we can leaf through to see the cells below.00:25:56.03The formation of the floral primordia,00:25:58.16for example,00:26:00.09this flower right here,00:26:02.17labeled P1,00:26:04.01starts out as a tiny primordium00:26:05.21and the bulges out to make the sort of primordia00:26:08.06that we saw on the scanning electron micrographs00:26:11.00on the last slide.00:26:12.17As a result of its establishment00:26:15.00as a very young primordium,00:26:16.26at this point in the flanks of the shoot apical meristem,00:26:20.01and then rapid cell divisions,00:26:23.06more rapid than those in the meristem,00:26:25.08so that it begins to bulge out,00:26:27.02create a separate primordium,00:26:28.28and grow away from the shoot apical meristem.00:26:30.24So, we can see that happening00:26:32.15in this time lapse image,00:26:34.03which is sped up about 3,000 times.00:26:37.09Now, the shoot apical meristem,00:26:39.15as I showed it to you,00:26:41.01looked quite homogenous.00:26:42.09All those cells in the meristem00:26:43.26looked the same as each other00:26:46.07in both of the types of the micrographs that I showed,00:26:48.17but they're really not the same.00:26:49.27Things are really a lot more complicated than that,00:26:51.28and just to demonstrate that00:26:54.03I'm showing here three different laser scanning confocal00:26:58.07microscope pictures00:27:00.11in which, up here,00:27:02.05we're looking at expression of a gene00:27:03.21called CUP-SHAPED COTYLEDONS 2,00:27:05.07which has been stained with a yellow fluorescent protein,00:27:08.07its promoter expresses a yellow fluorescent protein00:27:10.19in those cells where the CUP-SHAPED COTYLEDONS protein 200:27:14.03is normally expressed,00:27:15.28and we've false-colored that red,00:27:17.21and the place where the gene is expressed00:27:19.27is in the boundary region00:27:21.27between a flower primordium and the meristem.00:27:24.05So, those cells are different from the others.00:27:26.13This is a picture00:27:30.13where the green is a different gene called KANADI,00:27:32.19which is being expressed... KANADI 1...00:27:35.29which is expressed in front00:27:38.09of the primordia in those boundary regions,00:27:40.15but also around the back of each primordium00:27:44.05as it begins to form,00:27:46.13then later jumps up to the front,00:27:47.25so it's a very dynamic pattern of gene expression.00:27:50.07It's different from CUP-SHAPED COTYLEDONS 2.00:27:52.23Here are some other patterns of expression00:27:55.04that we're showing.00:27:57.04The red is SHOOT MERISTEMLESS,00:27:59.06a different gene that's expressed00:28:02.26in a completely different pattern in the meristem,00:28:04.17and if we add together all of these different patterns of gene expression00:28:06.29that we see in the shoot apical meristem,00:28:08.21there are dozens and perhaps hundreds00:28:11.03of different types of cells in the shoot apical meristem,00:28:13.29despite its uniform appearance.00:28:15.23So, it's a very complicated object,00:28:17.10but we have the methods00:28:19.15to see where the genes are expressed00:28:21.11and the methods to see00:28:24.08how the dynamics of that gene expression00:28:26.09changes as we intervene,00:28:28.07genetically and in other ways,00:28:29.18with the shoot apical meristem,00:28:30.29so that we can begin to develop00:28:32.27hypotheses of how it is that the meristem00:28:35.05chooses the position for its new flower and leaf primordium,00:28:38.11one time after the other,00:28:40.04in this spiral phyllotactic pattern.00:28:42.06So, this is where we end Part 1.00:28:44.17Tune in for Part 200:28:46.16and we'll say a little bit more about the phyllotactic pattern,00:28:48.28a little bit more about the methods,00:28:51.28and we'll show you how we use the methods00:28:54.06to develop a theory of phyllotactic pattern00:28:57.02that's tested and gives us predictive capability00:29:00.00so that we can change the genotype of the plant00:29:02.19in known ways,00:29:04.00and change the pattern in which the leaves00:29:06.00and in which the flowers00:29:07.22come out around the plant.00:29:09.20So, stay tuned for Part 2,00:29:13.05and let me just finish00:29:15.10by acknowledging my sources of funding in my laboratory,00:29:18.23in particular the Howard Hughes Medical Institute00:29:20.20and the Gordon and Betty Moore Foundation,00:29:22.19who have been very generous,00:29:24.17the Department of Energy,00:29:27.13whose funding has led entirely00:29:29.04to what will be Part 3,00:29:31.07the Gatsby Foundation in England,00:29:33.08and the National Institutes of Health,00:29:35.11all of whom have made it possible00:29:37.07for my laboratory to develop the methods I've talked about,00:29:40.12to take the approach we've discussed,00:29:43.14and to create the hypotheses and models00:29:45.22that we'll talk about in the next two episodes.
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