A Cell's Private Life: Researchers Peer Inside a Hidden Protein

August 30, 2009
A Cell’s Private Life: Researchers Peer Inside a Hidden Protein

Enlarge

(PhysOrg.com) -- To understand the molecular machinery of the human body, scientists have to be able to observe the structure of cellular proteins. This has been particularly challenging for those proteins embedded in cellular membranes. Now researchers from the Yale School of Medicine have established a novel way to peer inside this hidden universe, obtaining the first close-up look at a membrane-embedded potassium ion channel that, when defective, can cause high blood pressure or epilepsy. The research appears August 30 in Nature's Advance Online Publication.

The Yale team was able to visualize the so-called "BK" channel protein by using single-particle reconstruction. In this technique, individual protein molecules are imaged in an electron microscope, and information from thousands of images is combined to produce a three-dimensional map of the . This was the first time this reconstruction technique was extended to proteins embedded in membranes.

The researchers were able to see the BK channel protein’s voltage sensors, the calcium-sensing domains and other aspects of this critical cellular component. “The technique opens up a new way to study the many important molecular machines of cellular membranes,” said Fred Sigworth, Ph.D., of the Department of Cellular and Molecular Physiology at the Yale School of Medicine. “These machines include pumps, transporters and receptors as well as ion channels like the one visualized here.”

Although the first map did not have high resolution, Sigworth and his co-author Liguo Wang, Ph.D., say they are optimistic that better 3-D visuals will be obtained in the future. Furthermore, this technique will now allow the proteins to be caught in the act as they respond to cellular signals and transport their molecular cargoes across membranes.

Provided by Yale School of Medicine

4.3 /5 (3 votes)  

Filter


Move the slider to adjust rank threshold, so that you can hide some of the comments.


Display comments: newest first

mabarker
Aug 31, 2009

Rank: 1 / 5 (1)
I've had molecular pharmacology I & II at UCSD a few years back. It was fascinating. So much so that I took a class in advanced vertebrate immunology. In none of the many lectures in those 3 classes did the profs address macroevolution. As a biologist I really would like to know a darwinian step-by-step explanation of how - for e.g. - a calcium sensing domain can appear by random mutation(s). Help me in my unbelief.
Ethelred
Sep 02, 2009

Rank: 5 / 5 (1)
No way will I help you with your belief in Jehovah. You have to patch the flaws yourself.

Mutation is random but selection is NON-random. All modern cells have ports, both in and out. All that is needed for a channel to specialize is that a mutation in a channel be conserved because it helps survival. The first organism with such a development will have an advantage over those that do not have it. This works for any such specialization whether it be for chloride ion or calcium.

Of course the first step in such specialization is having at least one duplicate of the original gene. This sort of doubling can happen by either copying a section of the DNA more than once or by copying a whole chromosome or in bacteria a plasmid ring.

http://www.pubmed...der.fcgi?artid=1207871]http://www.pubmed...=1207871[/url]

That is likely to break so here it is in two lines.
http://www.pubmed...der.fcgi
?artid=1207871

And another
http://cat.inist.fr/?aModele=afficheN" title="http://http://cat.inist.fr/?aModele=afficheN" rel="nofollow" target="_blank">http://cat.inist....afficheN&cpsidt=13387202

Two line version
http://cat.inist.fr/
?aModele=afficheN&cpsidt=13387202

Basically you simply don't want to think about how it could happen. Much like Dr. Behe. He can't imagine things because he doesn't want to. His chapter on the Bombadier Beetle shows this quite clearly. And his chapter on the clotting cascade shows his refusal to think about the conditions that existed when it clotting became a important. Not once did he bother notice that early on organisms would not have been completely dependent on blood for survival.

The real question is not whether it could have evolved but why do you think it couldn't. The answer is clearly that you have a purely religious aversion to the whole concept of evolution.

Do you really believe there was world wide flood covering the highest mountains?

Will you ever actually discuss any of this or are you just going to continue with the hit and run posts?

Ethelred
Rank 4.3 /5 (3 votes)
Related Stories
Relevant PhysicsForums posts
  • Is Everyday Technology Killing Us?
    createdFeb 08, 2012
  • Exercise and weight loss
    createdFeb 08, 2012
  • Why do we have head aches? Our brains can't feel anything.
    createdFeb 07, 2012
  • "The end of diseases" by David Agus, interview from Daily Show with Jon Stewart
    createdFeb 04, 2012
  • Oncolytic adenovirus
    createdFeb 04, 2012
  • Nutrition label stuffs and diets
    createdFeb 02, 2012
  • More from Physics Forums - Medical Sciences

More news stories

Overeating may double risk of memory loss

New research suggests that consuming between 2,100 and 6,000 calories per day may double the risk of memory loss, or mild cognitive impairment (MCI), among people age 70 and older. The study was released today and will be ...

Medicine & Health / Neuroscience

created 3 hours ago | popularity 5 / 5 (2) | comments 0 | with audio podcast

Starve a virus, feed a cure? Findings show how some cells protect themselves against HIV

A protein that protects some of our immune cells from the most common and virulent form of HIV works by starving the virus of the molecular building blocks that it needs to replicate, according to research published online ...

Medicine & Health / Research

created 7 hours ago | popularity 5 / 5 (1) | comments 0 | with audio podcast

Declining health-care productivity in England: Who says so?

Reports that the National Health Service in England has been declining in productivity in the last decade appear to have been accepted as fact. However, a Viewpoint published Online First by The Lancet disputes this. The Vi ...

Medicine & Health / Health

created 1 hour ago | popularity not rated yet | comments 0

Injured boomers beware: Know when to see doctor

(AP) -- It happened to nurse Jane Byron years after an in-line skating fall, business owner Haralee Weintraub while doing "men's" push-ups, and avid cyclist Gene Wilberg while lifting a heavy box.

Medicine & Health / Health

created 8 hours ago | popularity 5 / 5 (1) | comments 0

FDA-approved drug rapidly clears amyloid from the brain, reverses Alzheimer's symptoms in mice

Neuroscientists at Case Western Reserve University School of Medicine have made a dramatic breakthrough in their efforts to find a cure for Alzheimer's disease. The researchers' findings, published in the journal Science, show t ...

Medicine & Health / Neuroscience

created Feb 09, 2012 | popularity 4.9 / 5 (58) | comments 17 | with audio podcast


Scientists discover molecular secrets of 2,000-year-old Chinese herbal remedy

For roughly two thousand years, Chinese herbalists have treated Malaria using a root extract, commonly known as Chang Shan, from a type of hydrangea that grows in Tibet and Nepal. More recent studies suggest that halofuginone, ...

New method to examine batteries -- MRI from the inside

There is an ever-increasing need for advanced batteries for portable electronics, such as phones, cameras, and music players, but also to power electric vehicles and to facilitate the distribution and storage of energy derived ...

A mitosis mystery solved: How chromosomes align perfectly in a dividing cell

Although the process of mitotic cell division has been studied intensely for more than 50 years, Whitehead Institute researchers have only now solved the mystery of how cells correctly align their chromosomes during symmetric ...

Lab study raises questions over nano-particle impact

Tests involving chickens have raised questions about the impact on health from engineered nano-particles, the ultra-fine grains commonly used in drugs and processed foods, scientists said on Sunday.

Google might launch Drive for cloud storage soon

(PhysOrg.com) -- Google's next big move, according to the Wall Street Journal, is a cloud storage service called Drive. Hardly first to the plate, Google is simply catching up to introducing its cloud reposi ...

Researchers find extensive RNA editing in human transcriptome

In a new study published online in Nature Biotechnology, researchers from BGI, the world's largest genomics organization, reported the evidence of extensive RNA editing in a human cell line by analysis of RNA-seq data, demons ...