Key protein interactions involved in neurodegenerative disease revealed

November 8, 2012, Scripps Research Institute

Scientists from the Florida campus of The Scripps Research Institute (TSRI) have defined the molecular structure of an enzyme as it interacts with several proteins involved in outcomes that can influence neurodegenerative disease and insulin resistance. The enzymes in question, which play a critical role in nerve cell (neuron) survival, are among the most prized targets for drugs to treat brain disorders such as Parkinson's disease, Alzheimer's disease and amyotrophic lateral sclerosis (ALS).

The study was published online ahead of print on November 8, 2012, by the journal .

The new study reveals the structure of a class of enzymes called c-jun-N-terminal kinases (JNK) when bound to three peptides from different protein families; JNK is an important contributor to stress-induced apoptosis (cell death), and several studies in animal models have shown that JNK inhibition protects against neurodegeneration.

"Our findings have long-range implications for ," said TSRI Professor Philip LoGrasso, who, along with TSRI Associate Professor Kendall Nettles, led the study. "Knowing the structure of JNK bound to these proteins will allow us to make novel substrate competitive inhibitors for this enzyme with even greater specificity and hopefully less toxicity."

The scientists used what they called structure class analysis, looking at groups of structures, which revealed subtle differences not apparent looking at them individually.

"From a structural point of view, these different proteins appear to be very similar, but the biochemistry shows that the results of their binding to JNK were very different," he said.

LoGrasso and his colleagues were responsible for creating and solving the crystal structures of the three peptides (JIP1, SAB, and ATF-2) with JNK3 using a technique called x-ray crystallography, while Nettles handled much of the data analysis.

All three peptides have important effects, LoGrasso said, inducing two distinct inhibitory mechanisms—one where the peptide caused the activation loop to bind directly in the ATP pocket, and another with allosteric control (that is, using a location on the protein other than the active site). Because JNK signaling needs to be tightly controlled, even small changes in it can alter a cell's fate.

"Solving the crystal structures of these three bound peptides gives us a clearer idea of how we can block each of these mechanisms related to cell death and survival," LoGrasso said. "You have to know their structure to know how to deal with them."

Explore further: Scientists identify key protein linked to acute liver failure

More information: "Structural Mechanisms of Allostery and Autoinhibition in JNK Family Kinases," December 5, 2012 print edition of Structure.

Related Stories

Scientists identify key protein linked to acute liver failure

September 7, 2011
New research from the Keck School of Medicine of the University of Southern California (USC) may help prevent damage to the liver caused by drugs like acetaminophen and other stressors.

Signaling to chromatin

January 3, 2012
(Medical Xpress) -- Scientists from the Friedrich Miescher Institute for Biomedical Research (FMI) in collaboration with their colleagues from the Department of Biosystems Science and Engineering of the ETH Zurich, describe ...

Recommended for you

Bioengineered soft microfibers improve T-cell production

January 18, 2018
T cells play a key role in the body's immune response against pathogens. As a new class of therapeutic approaches, T cells are being harnessed to fight cancer, promising more precise, longer-lasting mitigation than traditional, ...

Secrets of longevity protein revealed in new study

January 17, 2018
Named after the Greek goddess who spun the thread of life, Klotho proteins play an important role in the regulation of longevity and metabolism. In a recent Yale-led study, researchers revealed the three-dimensional structure ...

Weight flux alters molecular profile, study finds

January 17, 2018
The human body undergoes dramatic changes during even short periods of weight gain and loss, according to a study led by researchers at the Stanford University School of Medicine.

The HLF gene protects blood stem cells by maintaining them in a resting state

January 17, 2018
The HLF gene is necessary for maintaining blood stem cells in a resting state, which is crucial for ensuring normal blood production. This has been shown by a new research study from Lund University in Sweden published in ...

Magnetically applied MicroRNAs could one day help relieve constipation

January 17, 2018
Constipation is an underestimated and debilitating medical issue related to the opioid epidemic. As a growing concern, researchers look to new tools to help patients with this side effect of opioid use and aging.

Researchers devise decoy molecule to block pain where it starts

January 16, 2018
For anyone who has accidentally injured themselves, Dr. Zachary Campbell not only sympathizes, he's developing new ways to blunt pain.

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.