I3 Venture awards info

Emory is full of fledgling biomedical proto-companies. Some of them are actual corporations with employees, while others are ideas that need a push to get them to that point. Along with the companies highlighted by the Emory Biotech Consulting Club, Dean Sukhatme’s recent announcement of five I3 Venture research awards gives more examples of early stage research projects with commercial potential. This is the third round of the I3 awards; the first two were Wow! Read more

Take heart, Goldilocks -- and get more sleep

Sleeping too little or too much increases the risk of cardiovascular events and death in those with coronary artery disease, according to a new paper from Emory Clinical Cardiovascular Research Institute. Others have observed a similar U-shaped risk curve in the general population, with respect to sleep duration. The new study, published in American Journal of Cardiology, extends the finding to people who were being evaluated for coronary artery disease. Arshed Quyyumi, MD and colleagues analyzed Read more

Repurposing a transplant drug for bone growth

The transplant immunosuppressant drug FK506, also known as tacrolimus or Prograf, can stimulate bone formation in both cell culture and animal Read more

SMA

‘Matchmaker’ role for protein behind SMA

Motor neurons connect the spinal cord to the muscles. They can be a meter long in adult humans. SMA (spinal muscular atrophy) affects approximately 1 in 10,000 babies. It impairs the ability to move and breathe, and in its most severe form, kills before the age of two.

A puzzling question has lurked behind SMA (spinal muscular atrophy), the leading genetic cause of death in infants.

The disorder leads to reduced levels of the SMN (survival of motor neurons) protein, which is thought to be involved in processing RNA, something that occurs in every cell in the body. So why does interfering with a process that happens everywhere affect motor neurons first?

Scientists at Emory University School of Medicine have been building a case for an answer. It’s because motor neurons have long axons. And RNA must be transported to the end of the axons for motor neurons to survive and keep us moving, eating and breathing.

Now the Emory researchers have a detailed picture for what they think the SMN protein is doing, and how its deficiency causes problems in SMA patients’ cells. The findings are published in Cell Reports.

Wilfried Rossoll, PhD in the lab.

“Our model explains the specificity — why motor neurons are so vulnerable to reductions in SMN,” says Wilfried Rossoll, PhD, assistant professor of cell biology at Emory University School of Medicine [and soon moving to the Mayo Clinic in Jacksonville]. “What’s new is that we have a mechanism.”

Rossoll and his colleagues showed that the SMN protein is acting like a “matchmaker” for messenger RNA that needs partners to transport it into the cell axon.

RNA carries messages from DNA, huddled in the nucleus, to the rest of the cell so that proteins can be produced locally. But RNA can’t do that on its own, Rossoll says. In the paper, the scientists call SMN a “molecular chaperone.” That means SMN helps RNA hook up with processing and transport proteins, but doesn’t stay attached once the connections are made.

“It loads the truck, but it’s not on the truck,” Rossoll says. [Read the rest of Emory’s press release here.]

He also tells me that even though the two diseases affect very different age groups, SMA and ALS (amyotrophic lateral sclerosis) have two things in common: they both affect motor neurons and they both involve proteins that transport RNA. He says an emerging idea in the field is that SMA represents a problem of “hypo-assembly” while ALS is a problem of “hyper-assembly.”

Posted on by Quinn Eastman in Neuro Leave a comment