Scientists provide detailed view of brain protein structure: Results may help improve drugs for neurological disorders

October 10, 2012

Researchers have published the first highly detailed description of how neurotensin, a neuropeptide hormone which modulates nerve cell activity in the brain, interacts with its receptor. Their results suggest that neuropeptide hormones use a novel binding mechanism to activate a class of receptors called G-protein coupled receptors (GPCRs).

"The knowledge of how the peptide binds to its receptor should help scientists design better drugs," said Dr. Reinhard Grisshammer, a scientist at the NIH's National Institute of Neurological Disorders and Stroke (NINDS) and an author of the study published in Nature.

Binding of neurotensin initiates a series of reactions in . Previous studies have shown that neurotensin may be involved in Parkinson's disease, schizophrenia, , pain, and .

Dr. Grisshammer and his colleagues used X-ray crystallography to show what the receptor looks like in atomic detail when it is bound to neurotensin. Their results provide the most direct and detailed views describing this interaction which may change the way scientists develop drugs targeting similar neuropeptide receptors.

X-ray crystallography is a technique in which scientists shoot X-rays at crystallized molecules to determine a molecule's shape and structure. The X-rays change directions, or diffract, as they pass through the crystals before hitting a detector where they form a pattern that is used to calculate the of the molecule. These structures guide the way scientists think about how proteins work.

Neurotensin receptors and other GPCRs belong to a large class of which are activated by a variety of molecules, called ligands. Previous X-ray crystallography studies showed that smaller ligands, such as adrenaline and retinal, bind in the middle of their respective GPCRs and well below the receptor's surface. In contrast, Dr. Grisshammer's group found that neurotensin binds to the outer part of its receptor, just at the receptor surface. These results suggest that neuropeptides activate GPCRs in a different way compared to the smaller .

Forming well-diffracting neuropeptide-bound GPCR crystals is very difficult. Dr. Grisshammer and his colleagues spent many years obtaining the results on the neurotensin receptor. During that time Dr. Grisshammer started collaborating with a group led by Dr. Christopher Tate, Ph.D. at the MRC Laboratory of Molecular Biology, Cambridge, England. Dr. Tate's lab used recombinant gene technology to create a stable version of the neurotensin receptor which tightly binds neurotensin. Meanwhile Dr. Grisshammer's lab employed the latest methods to crystallize the receptor bound to a short version of neurotensin.

The results published today are the first X-ray crystallography studies showing how a neuropeptide agonist binds to neuropeptide GPCRs. Nonetheless, more work is needed to fully understand the detailed signaling mechanism of this GPCR, said Dr. Grisshammer.

Explore further: Common drugs initiate a molecular pas de quatre at the surface of the cell membrane

More information: White et al., "Structure of the agonist-bound neurotensin receptor." Nature, published online October 10, 2012. DOI: 10.1038/nature11558

Related Stories

Common drugs initiate a molecular pas de quatre at the surface of the cell membrane

July 26, 2011
G protein-coupled receptors (GPCRs) are popular drug targets, accounting for about one-third of approved drugs and many hundreds of drugs currently in development. They act as molecular switches that transduce extracellular ...

Understanding human transmembrane signalling

October 13, 2011
(Medical Xpress) -- New international collaborative research led by Stanford University, the University of Michigan and involving Trinity College Dublin recently published in Nature, increases our understanding of how a ...

Recommended for you

How defeating THOR could bring a hammer down on cancer

December 14, 2017
It turns out Thor, the Norse god of thunder and the Marvel superhero, has special powers when it comes to cancer too.

Researchers track muscle stem cell dynamics in response to injury and aging

December 14, 2017
A new study led by researchers at Sanford Burnham Prebys Medical Discovery Institute (SBP) describes the biology behind why muscle stem cells respond differently to aging or injury. The findings, published in Cell Stem Cell, ...

'Human chronobiome' study informs timing of drug delivery, precision medicine approaches

December 13, 2017
Symptoms and efficacy of medications—and indeed, many aspects of the human body itself—vary by time of day. Physicians tell patients to take their statins at bedtime because the related liver enzymes are more active during ...

Estrogen discovery could shed new light on fertility problems

December 12, 2017
Estrogen produced in the brain is necessary for ovulation in monkeys, according to researchers at the University of Wisconsin-Madison who have upended the traditional understanding of the hormonal cascade that leads to release ...

Time of day affects severity of autoimmune disease

December 12, 2017
Insights into how the body clock and time of day influence immune responses are revealed today in a study published in leading international journal Nature Communications. Understanding the effect of the interplay between ...

3-D printed microfibers could provide structure for artificially grown body parts

December 12, 2017
Much as a frame provides structural support for a house and the chassis provides strength and shape for a car, a team of Penn State engineers believe they have a way to create the structural framework for growing living tissue ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.