A solution that holds water
Name a biological function, and proteins called integrins are probably involved in it. Together, the 24 members of the integrin family allow cells to attach to one another and to the matrix that surrounds them. They help cells decide what to become, where to go, how to respond to their environments, and when to grow, divide or die.
Integrins’ ubiquity and versatility also mean that when cells bearing them go awry, these proteins can contribute to a range of diseases, from autoimmune diseases to cancer.
The FDA has so far approved six drugs that reduce the activity of specific integrins to treat illnesses such as multiple sclerosis and ulcerative colitis and to prevent blood clots from forming. To the disappointment of scientists, doctors and patients, however, other promising candidates have failed in clinical trials and curtailed integrins’ potential as treatment targets.
New work led by researchers at Harvard Medical School and Boston Children’s Hospital uncovers a reason for the failures — and offers a potential solution.
Taking a close look at an integrin involved in blood clotting, at HMS and Boston Children's and colleagues found that failed drugs for two different integrins inadvertently encourage the integrins to open up into their “on” position, potentially driving integrin activity instead of quelling it.
The team revealed that in its closed or “off” position, the integrin contains a water molecule held in place by a series of chemical bonds. The integrin ejects the water molecule when activated.
Once they learned what was happening, the researchers were able to design integrin blockers that coaxed the clotting protein into its “off” position by holding the water molecule in place with a nitrogen atom.
Further tests hinted that water molecules play the same role in other integrins, indicating that the team’s strategy could work more broadly.
The findings, , forge a clearer path for drug development and deepen researchers’ understanding of how integrins work normally.
“The same water-harnessing design principle has already been extended to another integrin, and structural information suggests that researchers can design drugs to target further members of the integrin family to treat diseases that cause great suffering,” said Springer.
“It’s always gratifying to work on a project that is both scientifically and medically important,” he added.
This article was republished with permission from Harvard Medical School.
Enjoy reading ASBMB Today?
Become a member to receive the print edition monthly and the digital edition weekly.
Learn moreGet the latest from ASBMB Today
Enter your email address, and we’ll send you a weekly email with recent articles, interviews and more.
Latest in Science
Science highlights or most popular articles
Can a hair-loss drug prevent heart disease?
With the approved medication finasteride, researchers in Illinois may have found a new way to kill two birds with one stone.
These proteins have been secretly managing your cells
Scientists have long known that histones spool DNA and help regulate genes. They may be doing a lot more.
At the Salton Sea, uncovering the culprit of lung disease
Scientists have long suspected a link between the dust and poor respiratory health. According to recent findings, the prime suspect is a naturally occurring toxin.
From the journals: MCP
The importance of sharing proteomics data. Detecting nitrotyrosine-containing proteins. Analyzing yeast proteasomes. Read about these recent articles.
Using a network to snare the cause of kidney disease
A microfluidic device that mimics blood capillaries may help in early detection, and proper measures could reduce the risk of renal failures.
All about cholesterol
The latest science on how blood levels of HDL, LDL and more relate to cardiovascular health.