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Guest Post: A time for everything – but speed it up, please!

jhalper — Mon, 12 Oct 2015 04:41:13 +0000

Guest Post: A time for everything – but speed it up, please!

Ziv Zwighaft

Ziv Zwighaft is a research student in the group of the Weizmann Institute’s Dr. Gad Asher. Their new findings reveal some intriguing connections between our circadian clocks – which tick according to cycles of day and night – metabolism and aging. Here is his description:

King Solomon said: “There is a time for everything, and a season for every activity under the heavens.”

Our research tries to take this insight into the condition of living creatures a few strides forward. How strictly does it apply? Our lives are regulated by a biological clock – it’s actually many clocks working in synergy, orchestrating our waking, sleeping and eating, our growth and life stages and, recent research suggests, our metabolism. So first and foremost, the new findings are strong support for the claim that our circadian clocks are strongly intertwined with our body’s metabolic activities. We showed that the daily changes in the levels of a group of essential metabolites called polyamines are regulated from two sides – both by eating times and by the ticking of the clock. Polyamines are naturally occurring metabolites that are known to play a role in various essential cellular processes, as well as pathologies. Our research shows that they also play an active role in setting the tempo of our internal timing. (The research revealed that polyamines both regulate and are regulated by a circadian clock. WSW)

Dysfunction in the clock can lead to a wide range of diseases, starting with sleep disorders and on to metabolic disorders like obesity and diabetes, and up to psychological illnesses.

One of the things I found most encouraging was our success in reproducing the results we obtained in tissue culture and raising them to the level of the whole animal. Here, a deviation from the natural polyamine levels translated into clock malfunction. For example, low levels of polyamines made the clock run slow, and this situation was reversible by enriching the diet with polyamines.

This phenomenon – a drop in polyamine levels and impairment in the clock’s accuracy – is typical of the process of aging. So by investigating the joins between two worlds – circadian clocks and metabolism – we able to demonstrate how to “rejuvenate” the internal pace of timekeeping in old mice.

This particular study is finished, but the work has not been completed. In these days we are continuing to look for additional connections between the circadian clocks and metabolic processes in the body; these connections may lead to new strategies in the war against age-related disease.

So bad news and good: On the one hand, polyamine levels of tend to drop as we age, and our internal clocks lose time. On the other hand, we get polyamines from food too. When the researchers added a polyamine supplement to the diets to old mice, their slow circadian clocks gained minutes.

Asher says that much more research will be needed before we can tell whether such food supplements will have an effect on aging in humans. In the meantime, however, it can’t hurt to stick to a healthy diet and add some extra edamame, peas or lentils to the menu.

jhalper Mon, 10/12/2015 - 00:41

Tags

induced pluripotent stem cells

circadian clocks

obesity

Hm?
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3022763/
doi: 10.3402/fnr.v55i0.5572

"... On the other hand, the cell growth promoting effect may also be negative in relation to cancer development. It has been shown that increased polyamine levels are associated with increased cell proliferation as well as expression of genes affecting tumor invasion and metastasis (21)."

Dear Hank,

You are right, elevation in polyamine levels had been previously linked with cancer development. With that been said, in our research we restored the polyamine levels to basal levels and worked well inside the physiological range and far from the pathological concentrations. Like many things in life, too much or too little from something might hurt you...

Thank you for commenting, hope you enjoyed our project.

Ziv

The fact it can cause cancer is pretty scary.

Basic chemistry might keep brain cells healthy

jhalper — Wed, 27 May 2015 04:34:38 +0000

Basic chemistry might keep brain cells healthy

“Inclusion bodies – those clumps of protein that are found in the brain cells of Alzheimer’s patients – are, sadly, a product of aging,” says Dr. Maya Schuldiner. “They can form naturally in practically all cells, but when these cells get old, the mechanism for clearing them away starts to fail.”

That is not great news for those of us who are already seeing signs of incipient dementia every time we forget a name or misplace our keys. But of course there is good news too. Schuldiner has discovered a “detergent” that cells make to wash away those nasty protein clumps. And she believes that, in the future, this detergent could provide the basis of drugs to treat neurodegenerative diseases, among them Alzheimer’s and Parkinson’s.

We put the word “detergent” in quote marks, but the truth is that the basic chemistry is pretty much the same as that of laundry soap: The two-part molecules have a fatty, water-repelling end and a water-loving end. The fatty end can attach to molecules of grease or protein; the water-loving ends latch on to the nearest water molecules to whisk the “dirt” away. In scientific terms, the proteins in the inclusion body become soluble.

"Laundry soap" in human cells: The Inclusion bodies are in red, lipid droplets in green

Schuldiner and her team realized this detergent was being produced when they saw lipid droplets – “little lard balls,” in Schuldiner’s words – tethered to the inclusion bodies they were investigating in yeast cells. These little lard balls turn out to be a bit more complex than they look. They produce a special kind of fat that is similar to a sterol (related to cholesterol) – when and only when there is an inclusion body in the cell. This sterol is what forms the detergent.

She says that she and her team were amazed to find evidence of detergents inside a cell. Since detergent molecules are basically indiscriminate in their actions – capable of clearing away all sorts of proteins and fats – the cell would need to produce them carefully and deliberately in place. Hence the physical tethering.

Her lab mostly works with yeast cells, which have, says Schuldiner, “the same inclusion body issues as human cells. They contain a protein that is nearly identical to the human one for tethering the lipid droplets. And, like the human ones, they suck at the removal process once they get old.” The group did repeat their experiments on human cells in lab dishes, finding similar results to their yeast cell studies. And Schuldiner points out that other studies have noted the lipid droplets around inclusions in the nerve cells of Alzheimer’s patients, but mostly ignored the deceptive little “lard balls.”

What gives her hope for treatment is that the detergent production is really “basic chemistry.” Clearly any potential drugs based on her group’s findings are, for now, in the speculation stage, but we can all hope for rapid advances in this area.

jhalper Wed, 05/27/2015 - 00:34

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The Poetry of Science IV

jhalper — Thu, 26 Feb 2015 07:19:52 +0000

The Poetry of Science IV

Manot Cave cranium

With a skull and Keats, there was little choice but to write about the new online items in rhyme. So with apologies to Shakespeare, Keats and the scientists, as well as the people at SpaceIL, here are today's grab bag of poems. As usual, follow the links.

On a Lone Cranium

Alas poor Yorick – We can only know

Where you lived all those eons ago

Walking, did you take those others in stride;

Human, yet strange, as they strode alongside?

Did your children wander forth,

Searching for a greener North?

Can your skull, a bit of bone,

Tell us where our seeds were sown?

To the Moon

There was a fine crew in Rehovot

That aimed for the Moon with a “space boat”

It’s barely a cart

But they’ve built it quite smart,

For cool science it’s bound to promote

In a Heartbeat

“Two hearts that beat as one,”

Just one beat? Where’s the fun?

Just one cell can beat as twenty

For your heart, love, that is plenty

Oh yes, and we have women PhDs, too. If you're an outstanding female Israeli PhD looking for help with your postdoc, click here.

jhalper Thu, 02/26/2015 - 02:19

Dull paleossiferous twit !
You've popped your poor skull like a zit
Now neither your glia nor seeds of the chia
Can make a great bust out of it

Getting the Whole Picture

jhalper — Thu, 12 Feb 2015 08:02:53 +0000

Getting the Whole Picture

What's in a picture?

Prof. Benny Shilo knows the value of a good picture. We recently mentioned his book: Life’s Blueprint, which uses photographs of things like bread dough and yeast cells to illustrate the process of biological development. Here is the image from the most recent piece we have uploaded on his research:

This is an individual Islet of Langerhans, as you’ve never seen it before. The white dots are the insulin-containing vesicles inside the beta cells, which both sense glucose levels and secrete insulin. Shilo and his team managed to get “close-up shots” of the individual cell membranes, and found that they have straight edges where both sensing and secretion functions are located.

We love the images in this new article on the work of Prof. Talila Volk because, aside from their eye-catching colors, these ones really do illustrate the story her work tells.

Volk’s work investigates how muscle fibers get renewed through exercise. It may all come down to a protein that senses muscle contraction and tells the DNA in the cell nucleus to make more muscle proteins.

In this image, red is muscle fiber in fruit fly larvae, green is nuclei (muscle fibers are large cells with multiple nuclei) (A) shows normal muscle fiber, the others show what happens when the protein is missing.

How does it work? This image says it all:

In the left image you can see how the protein structure encircles the cell nucleus. At the other end of its arms (red) it connects to the cell’s skeletal structure – the cytoskeleton. On the right, in green, you can see the protein structure. Its arms are springy – so that a pull on the end transmits a signal to the middle.

Volk and her group refer to the protein as a biological “mechanosensor,” and, indeed, there is something rather mechanical about the right-hand image.

Assuming that form follows function, Volk has surmised that similarly-shaped proteins in human muscle fibers do the same thing.

Third, we have some cancer research images from the lab of Prof. Lea Eisenbach:

These tell the story of anti-cancer immune activity. Tissue and tumor cells appear in blue, pink shows immune cells that attack the cancer cells. When tumor cells appear in the back, there are many immune cells (left); but in the brain (middle) the same tumor cells attract relatively few immune cells. In fact, the normal brain tissue (in the same brain) on the right has no immune cells. If you first inject the tumor into the rat’s back, where there is immune activity, and then inject the tumor cells from the back into the brain, the brain will be protected from the cancer.

And, oh yes, they are pretty too. This image, again from Talila Volk, of a 3-D computer model of a fruit fly larva muscle fiber was the inspiration for a sewing project:

jhalper Thu, 02/12/2015 - 03:02

Luring Stem Cells Down the Right Path

jhalper — Wed, 24 Dec 2014 20:21:59 +0000

Luring Stem Cells Down the Right Path

Getting cells to revert to a stem-like state – creating so-called induced pluripotent stem (iPS) cells – was a true revolution, but the technique invented in 2006 is only half the game. The first challenges include getting enough adult cells to undergo the “reprogramming” in culture to be of use and removing those traces of “priming” that distinguish them from true embryonic stem cells. The second is keeping them in the iPS state – that is, holding back their urge to differentiate – in lab conditions. And then there is the challenge of directing their differentiation in the way that you want, especially if you want to lure them down one of the very early developmental paths.

For Dr. Jacob (Yaqub) Hanna, the way forward lies in taking a step back and asking the fundamental questions: How does reprogramming work on the basic molecular level? Why does the reprogramming process – inserting four genes into adult cells – create cells that are almost, but not quite, the equivalent of embryonic stem cells? Why is it that mouse embryonic stem cells tend to be stable and easily manipulated in the lab, but human stem cells stubbornly insist on differentiating or degrading, as well as resisting methods that have been shown to work on mouse cells?

That last question has turned out to be crucial: It is by comparing mouse and human cells that Hanna and his lab group have gained an understanding of the genetic pathways in human cells that drive differentiation, and this understanding led them to create “better iPS cells.” We wrote about these “naïve” cells, which appear to be closer to the earliest embryonic stem cells, around a year ago saying: “The next step, of course, is directing the differentiation of the embryonic tissue to produce specific human tissues and organs. Hanna and his group are already on it.”

We are now pleased to report progress in that area. The cells that Hanna and his group have created in the lab in the course of their latest research are some of the most challenging: primordial germ cells, the precursor cells that appear just a week or two into embryonic development and eventually give rise to the sperm and ova. A group in Japan had produced them in mouse cells, but that feat was proving particularly tricky to reproduce in human cells.

Using the naïve cell technique they invented, Hanna and his team went on to create human primordial germ cells – in quantity. “We can produce enough of these cells in the petri dish to use them for further research,” says Hanna. “One of the most important things we discovered is that the process is regulated by a different master gene in humans than in mice. This shows that we need to learn more about how these cells are produced in humans.”

Images: Clusters of human embryonic stem cells that were differentiated to an early germ cell (PGC) state. Each color reveals the expression of a different gene. (top to bottom) NANOS3, NANOG, OCT4 and all three combined in a single image

jhalper Wed, 12/24/2014 - 15:21

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primordial germ cells

Genetic Drifters

milhayser — Mon, 08 Dec 2014 15:33:50 +0000

Genetic Drifters

On Pharyngula, PZ Myers criticizes the stubborn obfuscations of Michael Behe, who refuses to yield his illogical calculations. Behe says (rightly) that a certain mutation necessary for drug resistance in the malaria parasite has about a 1 in 10²⁰ chance of occurring. But the mutation is also detected in 96% of malaria patients who respond well to the drug; it proliferated widely because, by itself, it had no impact on the parasite's fitness. The parasite needed another mutation, occurring at a later date, to develop resistance to the drug. Behe rests his case for divine intervention on the basis of bad math; as PZ writes, "It was crude, stupid, and ridiculous when J. Random Creationist was doing it, and it’s even worse when a guy with a Ph.D. in biochemistry, who ought to know better, panders to the mob of creationists who don’t even grasp middle school mathematics by using fallacious operations in probability." Meanwhile, Orac reports that one of the flu strains targeted by this year's vaccine "has undergone what is referred to as 'genetic drift,'" making the vaccine less effective than desired. Yet the vaccine still offers protection against about 57% of circulating strains. On Life Lines, Dr. Dolittle shares research that says consuming caffeine while pregnant can effect genes in the baby's heart. In total, researchers "identified 124 genes and 849 transcripts that were altered by exposure to caffeine in utero." And on ERV, Abbie Smith reviews the evolutionary trajectory of HIV, which may be tending toward a 'truce' with human hosts.

milhayser Mon, 12/08/2014 - 10:33

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Can't get to

"ERV, Abbie Smith reviews the evolutionary trajectory of HIV,"

becase advertisements forcibly redirect. A pity.

Using Ubuntu

Maybe scrap Ubuntu. Those ads shouldn't be coming from SB.

Life's Blueprint

jhalper — Wed, 29 Oct 2014 06:07:58 +0000

Life's Blueprint

A new book will make you stop and think about the relationship between the microscopic world and the one we pass by every day.

Life’s Blueprint – The Science and Art of Embryo Creation; Benny Shilo, Yale University Press, 174 pages.

Stem cells and their niche

When a stem cell divides, one daughter maintains the stem cell fate while the other produces a differentiated progeny. Stem cells are positioned in a restricted spatial niche that provides signals maintaining them in a proliferative, nondifferentiated state. After division, only the undifferentiated progeny is retained in the niche. Top: Once the eye of the zebrafish (Danio rerio) is specified, cells differentiate and produce neurons that sense light. Retinal stem cells (red) are maintained throughout the animal’s life in a niche located next to the lens (K. Cerveny and S. Wilson, University College London); bottom: The live yeast stock, or mother, is carefully maintained in the bakery. Portions are allocated to produce dough and bread. A fine balance is kept to ensure a steady production of bread while continuing to propagate the yeast stock (B. Shilo, Hi Rise Bakery, Cambridge, Massachusetts)

One and one can equal one – or two. But sometimes one and one goes way beyond the question of quantity – into the realm of elaborate qualification. When a sperm penetrates an egg – the two begin as one: a single, fertilized cell. That cell, of course, begins another operation: division. At first the cells are identical, but soon a process begins that leads, in the end, to a many-celled, autonomous organism. The same process occurs in flies, humans and pretty much all the life that was can see.

In Life’s Blueprint, Prof. Benny Shilo of the Weizmann Institute of Science describes the precisely-orchestrated concert that is embryonic development (at least everything we know today about the process). This is one of the most complex processes in nature, from the point of view of the number of factors involved, the precision timing required for each step, regulating the concentrations of substances that shape the developing embryo, the ability to copy information with great accuracy (though not absolute – a few “typos” are necessary to drive natural selection and thus evolution), and more.

How cell signaling establishes a repeated pattern

The compound eye of the fruit fly is made up of eight hundred repeated units called ommatidia. During eye development, patterning takes place progressively from the bottom to the top of the picture, generating a new row of ommatidia every two hours. Once an ommatidium is established, it signals to inhibit cells at the immediate radius from assuming a similar fate. The newly formed ommatidia become spaced at fixed distances, just outside this radius. Once created, they will now generate their own inhibitory spheres, to outline spacing of the next row of ommatidia that will form. Top: Establishment of the founder cells (blue) for ommatidia during eye development (A. Shwartz and B. Shilo, Weizmann Institute); bottom: Pigeons sitting on a railing establish a fixed spacing (B. Shilo, Moss Landing, California)

Shilo's book, written for a popular readership, avoids excess detail and scientific jargon. Other books may describe embryonic development, but with the photos, this book adds a level of philosophical treatise to the concise descriptions. The photos – all taken by Shilo – are presented in pairs (one plus one); each pair contains one image of an important stage in embryonic development alongside a photo from the world of our human, everyday objects. Their message is unambiguous and precise: a statement about the rules and plans that shape our world – both the seen and the unseen.

jhalper Wed, 10/29/2014 - 02:07

Tags

Elegance vs. complexity in biology

Embryonic development

Photos

Benny Shilo

Book

embryonic development

A Matter of Time

jhalper — Wed, 05 Feb 2014 08:31:16 +0000

A Matter of Time

The next time you reach into the fridge for a midnight snack – take heed: New research by Weizmann Institute scientists has shown that the time at which you eat your meals might have a profound effect on your liver triglyceride levels. Their research was conducted on mice, but if found to be true for humans as well, it may have clinical implications in the way patients could be treated for fatty liver and other metabolic diseases, which are characterized by abnormally elevated levels of lipids in blood and liver cells.

Our bodies are naturally cued to carry out various biological processes such as eating and sleeping at certain times of the day, and disruptions to this timing system, for example, eating at inappropriate times, may disturb the body’s natural rhythm and lead to disease. It’s no coincidence that shift-workers or those who travel frequently have been found to have a higher incidence as fatty liver and obesity, among other diseases.

Dr. Gad Asher of the Weizmann Institute’s Biological Chemistry Department researches the "biological clocks" known as circadian rhythms that are responsible for the fluctuating behavior of various biological processes. He and his colleagues have discovered that the levels of triglycerides – those nasty lipids that can build up in the liver and contribute to various heart problems – are regulated by these biological clocks, with their levels rising and falling according to a specific timetable. No big shocker there, but their next finding was quite surprising: When they restricted the mice’s meals to nighttime hours only, they saw a shift not only in the time the triglycerides had accumulated in the liver, but they observed a dramatic 50% decrease in overall levels. (And before you go ahead and open that fridge – remember: Mice are nocturnal animals so whatever works for them would be the opposite in us, humans.)

No drugs currently available for treating hyperlipidemia and hypertriglyceridemia – common diseases characterized by abnormally elevated levels of lipids in the blood and liver cells – have been shown to change lipid accumulation as efficiently and drastically as simply adjusting meal time. In other words, this research could lead to an alternative therapeutic intervention for such diseases: simply adjusting mealtimes. As an added benefit, one would not have to suffer any of the side effects usually associated with the drugs.

Not only that, but the scientists say it could have some farther-reaching implications. Just think about blood tests: These are usually only carried out in the morning hours, often after a fast. It is possible that the same test, carried out in the late afternoon, would yield different results? And the same holds true for animal researchers: Their data could depend on the timing of samples or feeding schedules.

jhalper Wed, 02/05/2014 - 03:31

Tags

lipid accumulation in liver

triglyceride level

USA Science & Engineering Festival

circadian clocks

inflammation

obesity

And what is the case for humans who are basically nocturnal, or who are completely detached from the conventional clock and don't usually see daylight?

Both of those are norms in the culture of programmers and related engineering professions. Someone needs to study the time-related health variables in this sector of society, upon whom we depend for much of our modern infrastructure.

Other researchers do, indeed, look at the human cost (see above in the post). The above kind of study can find the exact biochemical mechanisms, which can then be applied to people. One of the problems with doing such studies in humans -- involving diet -- is in that you would not only have to take the timing into account, but to adjust for take-out pizza and coffee consumption. Clearly more research is needed, but ask yourself: How much of that programming really needs to get done at night?

It is very interesting how this plays out in the mice, but I have to question, how do other factors (like differences in circadian rhythms as G mentioned) have an effect on humans? It would also be useful and engaging to see how different individuals of varying gender and age groups would react to this study. According to the National Sleep Foundation, adolescents have a delay in their biological clock. As a teenager very interested in health and medicine, I would be curious to know the difference this age/circadian rhythm change causes on the liver triglyceride levels and how it would affect my meal times. Or if it would even make that big of a difference?

Dr. Gad Asher replied: I do not have a good answer, in fact this is a very good question and future studies will hopefully provide an answer to these questions.
To date our studies are mostly limited to animal models which are well controlled.

If an optimum time was found that the biological processes are occurring within the animal could you therefore have more control on obesity and heart disease that occur and possibly limit the animal to these? Also if studied on humans would this have the same effect?

Studies would have to be carried out on humans, of course.

This is very interesting. It has never occurred to me that time can play a major role based on our biological factors. I have noticed that if I come home from a long, busy day without eating during my usual time, a disturbance in my body when I eat my "midnight dinner." I notice that I feel a little different (not by a whole lot) and it becomes harder to sleep at night right after I eat. But why does a change in your biological clock make sure a huge different later down the road on your body. For example, when someone moves to a new place over seas and they have to adjust to the time zone there, can this cause my problems down the road when they have to fully adjust to this for possible the rest of their lives? Do you think it affects younger people more, the same, or less than someone who is older? Also, based on what you eat at night I presume plays a role in how much or how little it can effect your body. Since our bodies have a nature way of healing ourselves, like forming scabes after cuts and getting better after a cold- because our homeosstatesis plays a role, it could be possible that if a person where to remain stable with a constant time on sleeping, eating etc. that the diseases possibly caused from this down the road can be "re-winded?" Do you think this can play a role in cancer also?
Diseases that can be caused from a disturbance does make sense because our bodies are like a machine and if the machine is not treated properly with care and maintenance the time of the machine will not work long.

I found this article very interesting. The title caught my eye but I didn't expect this is what the article would be on. I am very interested in weight loss and weight management and have done some research on it before based on past experience and other peoples experiences. I have heard from people that late night cravings and snacking is bad for you but never found an article based on it like this one. This makes me rethink the next time I want a snack before bed. It makes me curious how Dr Asher thought to study the circadian rhythm to see how our trygluceride levels are effected. It is interesting to think that we could find the cure to beat obestiy and heart diseases that has been effected Americans for years. When could they start doing these types of testing on humans since they have only been testing mice? And what kind of an effect do you think this kind of testing would have on humans?

I found this article to be very interesting but it's not exactly new information. It's common knowledge to not eat after a certain time to benefit a healthy weight just like it is common knowledge not to eat McDonalds when dieting. However, I think it needs to become more known just how much the late night eating can set people back when trying to maintain a healthy diet. I would be curious to know if this pertains to all "midnight snacking" or if there are certain foods that will not disturb our biological clocks. Say you eat celery at one a.m. Celery does not have much nutritional value so will that throw our clocks out of wack as well. I realize it will not have the same effect as eating a burger at this same time but my question still stands if it is ok to eat late at night if it is something healthy.

Again, the study was done on mice -- it won't tell you what a human can eat at night. The surprise was not that our eating has a biological clock function, but that there is another clock, on top of the first one, that strongly regulates lipid storage in the liver.

I found this article to be very interesting and relatable! I constantly try to watch what I eat. We always seem to get hungry when we shouldn't get hungry. Like we want what we can't have. I've read other articles by Dr. Asher where he is talking about the biological clock. This tells us whether we should wake up, if it's time to go to bed, etc. This helps you decide when it may be "too late" to eat. I'm interested to see what happens to those who may work all night and work all day., or are just nocturnal. I think that it is cool that we are able to use mice as experiments before we use humans. Are there other animals that we could use to experiment on? I think this is interesting because everyone of us can relate to us whether we like to watch what we eat or we don't have a care in the world! Either way these experiments are working closer to reduce the amount of heart disease and obesity!

Spotlight on X-STEM Speaker Dr. Robert Tjian

carlyo — Tue, 05 Nov 2013 17:04:53 +0000

Spotlight on X-STEM Speaker Dr. Robert Tjian

X-STEM - presented by Northrop Grumman Foundation and MedImmune - is an Extreme STEM symposium for elementary through high school students featuring interactive presentations by an exclusive group of visionaries who aim to empower and inspire kids about careers in science, technology, engineering and mathematics (STEM). These top STEM role models and industry leaders are sure to ignite your students’ curiosity through storytelling and live demonstrations.

Our spotlight on our X-STEM Speakers continues with Biochemist Dr. Robert Tjian from Howard Hughes Medical Institute (HHMI).

Ask colleagues about biochemist Robert Tjian and the qualities that best define him, and you will most likely be told such accolades as: "A distinguished, first-rate scientist... a person of impeccable talent and taste in science who commands a great breadth of understanding across the life sciences... a highly productive scientist but also a committed teacher and mentor of young scientists."

These characteristics are among the traits that have molded Robert throughout his prominent career as a researcher and professor, and led to his appointment in 2008 as president of the prestigious Howard Hughes Medical Institute (HHMI) -- one of the world's largest philanthropies, and an organization which plays a powerful role in advancing biomedical research and science education in the United States.

"This is the most interesting job for a scientist in the nation - if not the world - because of its impact on research in the life sciences," says Robert of his job at HHMI. "I feel a sense of responsibility after more than 20 years as an investigator with HHMI. It is a great opportunity to give back in a significant way."

The Institute, a non-profit medical research organization with an endowment of more than $17.5 billion, has over the past two decades made investments of more than $8.3 billion for the support, training and education of the nation's most creative and promising scientists.

Before assuming his position as president of HHMI in 2009, he was a distinguished professor and researcher of biochemistry and molecular biology at the University of California, Berkeley, where he had also served as an HHMI investigator since 1987, carrying out groundbreaking science with his team at UC Berkeley as well as at HHMI's prestigious Janelia Farm Research Campus in Virginia.

Specifically, Robert is widely known for his studies into how genetic information stored in DNA is copied (transcribed) into RNA, which directs the production of proteins inside cells that are essential to life. He devised a way to isolate the individual components of the cell involved in transcription and recreate this complex, highly regulated process in a test tube. Advances in technology have also enabled Tjian to purify rare sequence-specific transcription factors, which bind to DNA at specific sites and regulate the expression of genes, and to isolate the genes that encode these important transcription factors.

His work has provided new insights into the molecular mechanisms that underlie various human diseases and conditions, including Huntington's disease, cancer, diabetes, and infertility.

Robert has also been actively involved in training a new generation of molecular biologists who are poised to answer new questions generated by today's scientists. "It gives me great pride to have guided so many students into medical careers, and to watch my students and postdoctoral fellows develop into first-rate scientists," says Robert.

In addition to spearheading HHMI's formidable medical research initiatives as Institute president, he is also committed to advancing the Institute's long commitment to science outreach to students. Says Robert: "HHMI is committed to funding education programs that excite students' interest in science. We hope that these programs will shape the way students look at the world -- whether they choose to pursue a career in science or not."

Robert was born in Hong Kong, the youngest of nine children. His family fled China before the Communist Revolution and eventually settled in New Jersey. Known as a voracious consumer of scientific information and data, Tjian famously talked his way into the biochemistry laboratory of the late Daniel Koshland as a Berkeley undergraduate - even though he had never taken a single course in the subject.

Robert went on to receive a Bachelor's degree in Biochemistry from Berkeley in 1971 and his Ph.D. from Harvard University in 1976. After completing a post-doctoral fellowship at the Cold Spring Harbor Laboratory with James Watson, he joined the Berkeley faculty in 1979 where he later assumed a variety of leadership roles, including serving as Director of the Berkeley Stem Cell Center, and the Faculty Director of the Li Ka Shing Center for Biomedical and Health Sciences. He is a member of the National Academy of Science and has received many awards honoring his scientific contributions, including the Alfred P. Sloan Prize from the General Motors Cancer Research Foundation, and the Louisa Gross Horwitz Prize from Columbia University. He was named California Scientist of the Year in 1994.

Click here for more information.

carlyo Tue, 11/05/2013 - 12:04

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X-STEM