Category Archives: Physiology

3 U.S.-based scientists win Nobel in physiology or medicine

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Three scientists who study the inner workings of cells have won the 2013 Nobel Prize in physiology or medicine for their work in unraveling the mystery of how proteins, hormones and other molecules are moved around inside cells and exported to other parts of the body.

The Nobel committee lauded Randy W. Schekman of UC Berkeley, Thomas C. Suedhof of Stanford University and James E. Rothman of Yale University for making known "the exquisitely precise control system for the transport and delivery of cellular cargo. Disturbances in this system have deleterious effects and contribute to conditions such as neurological diseases, diabetes and immunological disorders."

The announcement was made Monday in Stockholm.

"It's a fundamental discovery of cell physiology, and it was not entirely easy for these investigators when they started," Juleen Zierath, chairwoman of the committee that awarded the prize, said in an interview posted on the Nobel website.

For decades, the three molecular and cellular biologists have studied the cell's intricate internal transport system in which bubble-like vesicles shuttle key molecules including neurotransmitters and enzymes to different parts of the cell and through the cell's membrane.

"Think of a cell as sort of a factory, and it needs to produce proteins," said Zierath, a professor in clinical integrative physiology at the Karolinska Institute in Sweden. Cells "need to shuttle these proteins and cargo from one workstation to the next, so each protein can get a little bit better refined along the way."

The researchers had been considered among the top contenders for the award, which is worth about $1.2 million. Schekman and Rothman were joint winners of the prestigious Albert Lasker Basic Medical Research Award in 2002, and Suedhof was recognized with the award last month.

At a news conference in Berkeley, Schekman said he was aware of the speculation but didn't think he would win.

But hours after returning from an award ceremony in Germany, the 64-year-old was awakened at 1:30 a.m. by a ringing phone and his wife, Nancy, shouting, "This is it! This is it!"

"My heart was pounding and I was trembling," Schekman said. "But then I heard a comforting voice with a thick Swedish accent congratulating me."

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3 U.S.-based scientists win Nobel in physiology or medicine

Three American Scientists Win 2013 Nobel Prize In Physiology Or Medicine

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October 7, 2013

Image Caption: The three 2013 Nobel Prize in Physiology or Medicine winners. (Left to right) James E Rothman - Credit: Yale University / Randy Schekman - Credit: H. Goren HHMI / Thomas C. Sudhof - Credit: S. Fisch

Brett Smith for redOrbit.com Your Universe Online

Three scientists at American universities were awarded the 2013 Nobel Prize in Physiology or Medicine for their work describing the cellular machinery behind the transport and secretion of proteins in the bodys cells.

Based on their experiments with yeast, the scientists Randy W. Schekman from the University of California at Berkeley, Thomas C. Sdhof from Stanford University and James E. Rothman from Yale University were able to reveal new details about a fundamental process in cell physiology.

In a statement, the 50-member Nobel Assembly praised the scientists for describing the exquisitely precise control system for the transport and delivery of cellular cargo. Disturbances in this system have deleterious effects and contribute to conditions such as neurological diseases, diabetes, and immunological disorders.

My first reaction was, Oh, my god! said Schekman, who was awakened with the good news at 1:30 a.m. PST. That was also my second reaction.

Schekman and Rothman worked separately to describe the cellular system that ferries hormones and enzymes out and grows the cell membrane surface so the cell can divide and multiply. The system utilizes tiny bubbles on the cell membrane to shuttle molecules about the cell interior and is so important that mistakes in the system inevitably lead to death.

Ten percent of the proteins that cells make are secreted, including growth factors and hormones, neurotransmitters by nerve cells and insulin from pancreas cells, Schekman said.

In what seemed like a questionable decision at the time, Schekman began investigating this system in yeast starting in 1976. During the following years, he discovered more and more details on how yeast cells arrange, wrap up and send proteins using membrane bubbles, a highly important process in yeast communication and in mating. The process also delivers receptors to the surface of the yeast cell, its primary way of controlling the intake of nutrients.

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Three American Scientists Win 2013 Nobel Prize In Physiology Or Medicine

2013 Nobel Prize In Physiology Or Medicine Awarded To Three Scientists For Cell Transport System Research

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Rothman, 63, is the chairman of Cell Biology at Yale University, earning his B.A. at Yale University and his Ph.D. at Harvard University. Schekman, 64, is a professor at the University of California, Berkeley and an investigator at Howard Hughes Medical Institute. Sdhof, 58, is a German researcher currently working at the Stanford School of Medicine.

The Nobel Assembly at Karolinska Institutet announced the 2013 Nobel Prize in Physiology or Medicine on Monday. According to the committee, "The three Nobel laureates have discovered the molecular principles that govern how this cargo is delivered to the right place at the right time in the cell." Vesicles carry hormones, growth factors, enzymes and other molecules throughout the cell in a process known as "vesicle traffic," reports the Associated Press.

According to the committee, Rothman discovered proteins that are required for the docking and fusing with their targeted membrane. Schekman was recognized for his work on discovering what genes were necessary for vesicle traffic, necessary for directing the flow of traffic within the transport system. Sdhof discovered the signaling process for vesicles to release their cargo. In a press release from Berkeley, Schekman said when he heard the news, "my first reaction was, Oh, my god! That was also my second reaction." Sdhof had a similar reaction, asking, "Are you serious?"

The research on the cell transport system could lead to new insights, and possible treatments, for diseases such as diabetes, tetanus and other immune diseases, notes AP. Schekman said some forms of diabetes and a form of hemophilia are caused by an error in the secretion system of cells, and his work with yeast helped lead to the creation of insulin made from yeast. Schekman's current research involves looking at this secretion system and a possible link to Alzheimer's disease.

The trio will share the prize money of 8 million Swedish kronor, approximately $1.2 million, reports AP. The 2013 Nobel Prize in Physics will be announced on Oct. 8.

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2013 Nobel Prize In Physiology Or Medicine Awarded To Three Scientists For Cell Transport System Research

2013 Nobel Prize in Physiology or Medicine won by researchers at Yale, Berkeley, and Stanford

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Yale's Fergus F. Wallace Professor of Biomedical Sciences James E. Rothman, UC Berkeley's Professor of Molecular and Cell Biology Randy W. Schekman, and Stanford's Professor of Molecular and Cellular Physiology Thomas C. Sdhof today were jointly awarded the 2013 Nobel Prize in Physiology or Medicine. The Nobel Assembly at Karolinska Institutet in Stockholm, which awards the prize in physiology or medicine, cited "their discoveries of machinery regulating vesicle traffic, a major transport system in our cells"

Winners of the 2013 Nobel Prize in Physiology or Medicine James E. Rothman, Randy W. Schekman, and Thomas C. Sdhof, together with a diagram summarizing their discoveries (Photo: Nobel Foundation)

The new laureates responded to the announcement in a variety of ways. Professor Rothman was "completely shocked and surprised." Professor Schekman "danced around with my wife and repeatedly said 'oh my god, oh my god'" and Professor Sdhof simply said "Are you serious?".

The process of choosing a particular discovery for recognition from among the hordes of truly fine work nominated for the Prize (380 nominations this year) is quite difficult. In the end, the Nobel Assembly is seeking "a discovery that has changed the paradigm in an area of physiology or medicine, one who has changed our understanding of life or the practice of medicine."

The existence of every living cell depends on the production and transport of a huge range of molecules within the cell. Many of these molecules must be exported from the cell, such as insulin, which acts within the blood stream, and neurotransmitters, which function in the synapses between nerve cells. However, most molecules are too large to pass freely through internal or external cellular membranes. To get around this problem, large molecules are packaged within vesicles, in which they are wrapped within small spherical membranes having a structure closely related to that of the cellular membrane.

The newest Nobel Laureates won the prize for sorting out just how vesicles manage the precise timing and location required for delivery of their contents. In the 1970s, Professor Schekman studied the genetic basis for vesicle formation and control. He used yeast cell strains whose genetics produced defective vesicle control, in which vesicles piled up in specific parts of the cell. By identifying the mutated genes, Schekman identified three classes of genes that control the machinery that determines how a cell forms and transports vesicles to maintain its health.

In the 1980s and 1990s, Professor Rothman studied vesicle transport in mammalian cells. He discovered that a particular protein complex provides the machinery that lets vesicles dock and fuse with the membranes for which they are targeted. These vesicle binding proteins only allow a given vesicle to transport its cargo through the right type of membrane one that has matching proteins embedded in its structure, which ensures that the contents of a vesicle are delivered only to their intended location. The process is controlled by the same genes Schekman had discovered in yeast cells, indicating that vesicle transport has survived the evolutionary process for at least half a billion years.

Professor Sdhof is a neuroscientist who is interested in how nerve cells communicate. While it was known that neurotransmitters are released from vesicles as described by Rothman and Schekman, these vesicles only open when a nerve cell communicates with its neighbors. In the 1990s, he decided to study how this very specific behavior was controlled. He identified molecular machinery that triggers the vesicles to bind to a nearby cell membrane when in the presence of calcium ions, thereby explaining how the contents of a vesicle can be liberated by external control.

This year's monetary prize has been set at eight million Swedish kroner, or about $1.25 million US dollars. The prize money is usually split even between multiple Laureates. The Nobel Prize Award Ceremonies will be held in Stockholm on December 10.

Source: Nobelprize.org

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2013 Nobel Prize in Physiology or Medicine won by researchers at Yale, Berkeley, and Stanford

Physiology of Sodium and Potassium Balance (Renin, Angiotensin, Aldosterone, and ADH) – Video

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Physiology of Sodium and Potassium Balance (Renin, Angiotensin, Aldosterone, and ADH)
A review of the normal physiology of sodium, potassium, and water. Major topics covered include the renin angiotensin aldosterone system, the hypothalamic pi...

By: drericstrong

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Physiology of Sodium and Potassium Balance (Renin, Angiotensin, Aldosterone, and ADH) - Video