Navigation Links
Discovery of Agile Molecular Motors Could Aid in Treating Motor Neuron Diseases

Over the last several months, the labs of Yale Goldman, MD, PhD, Director of the Pennsylvania Muscle Institute at the University of Pennsylvania School of Medicine,// and Erika Holzbaur, PhD, Professor of Physiology, have published a group of papers that, taken together, show proteins that function as molecular motors are surprisingly flexible and agile, able to navigate obstacles within the cell. These observations could lead to better ways to treat motor neuron diseases.

Motor neuron diseases are a group of progressive neurological disorders that destroy motor neurons, the cells that control voluntary muscles for such activities as speaking, walking, breathing, and swallowing. When these neurons die, the muscle itself atrophies. A well-known motor neuron disease is amyotrophic lateral sclerosis (ALS, commonly known as Lou Gehrig’s disease).

Using a specially-constructed microscope that allows researchers to observe the action of one macromolecule at a time, the team found that a protein motor is able to move back and forth along a microtubule – a molecular track – rather than in one direction, as previously thought. They report their findings in a recent issue of Nature Cell Biology. The proteins in this motor, dynein and dynactin, are the “long-distance truckers” of the cell: working together, they are responsible for transporting cellular cargo from the periphery of a cell toward its nucleus.

“My lab concentrates on the cellular and genetic aspects of the dynein-dynactin motor, while Yale’s group delves into the mechanics of the motor itself,” says Holzbaur. “We’re deconstructing the system to understand how it all works in a living cell. In the lab, we start with a clean microtubule with a motor walking across it, but in the cell it’s different: microtubules are packed together, with proteins studded along them, and cellular organelles and mitochondria are crammed in. The motor needs to maneuver around those ‘obstructions.’” Goldman and Holzbaur suggest that the ability of the dynein-dynactin motor to move in both directions along the microtubule may provide the necessary maneuvering ability to allow for effective long distance transport.

Earlier this year, as reported in The Journal of Cell Biology, researchers in Holzbaur’s lab found that a mutation in dynactin leads to degeneration of motor neurons, the hallmark of motor neuron disease. This mutation decreases the efficiency of the dynein-dynactin motor in “taking out the trash” of the cell, and thus leads to the accumulation of misfolded proteins in the cell, which may in turn lead to the degeneration of the neuron.

Scientists are now finding that many other molecular motors are remarkably flexible in their behavior. In several further papers published in the Proceedings of the National Academy of Sciences and The EMBO Journal, Goldman and colleagues at the University of Illinois found that a “local delivery” motor, termed myosin V, moves cargo with a variable path short distances along another type of cellular track called actin. This flexibility could help myosin V navigate crowded regions of the cell where the actin filaments criss-cross and where other cellular components would otherwise pose an impediment to motion. Defects in myosin V function also result in neurological defects.

Most of these molecular motors are associated with specific diseases or developmental defects, so understanding the puzzling aspects of their behavior in detail is necessary for building nanotechnological machines that, for example, could replace defective motors. “The ultimate goal is to find ways to treat motor neuron disease as well as other diseases that involve cellular motors and also construct nano-scale machines based on these biological motors,” says Goldman.

(Source: Newswise)

Related medicine news :

1. Discovery of bone gene
2. New Discovery May Help Treat Infertility
3. New Discovery to Increase Survival of Breast cancer Patients
4. Discovery of World’s smallest laser
5. Discovery of a built-in fat sensor
6. OHSU Researchers Announce New Discovery
7. Discovery Of New Molecule Could Solve Cancer Spread Mystery
8. Discovery Of Human Skeletons Could Unfold Facts About By-Gone Ages
9. New Discovery Shows That Brain Could repair Itself After Stroke
10. New Sleep Gene Discovery Wakes Up Scientists
11. Discovery of Elevated Amyloid Peptide levels could lead to Alzheimer’s Preventio
Post Your Comments:

(Date:6/26/2016)... ... ... PawPaws brand pet supplements owned by Whole Health Supply is ... of felines. The formula is all-natural and is made from Chinese herbs that have ... Kidney Support Supplement Soft Chews are Astragalus Root Extract and Rehmannia Root Extract ...
(Date:6/25/2016)... ... June 25, 2016 , ... Austin residents seeking Mohs surgery ... of Mohs Surgery and to Dr. Russell Peckham for medical and surgical dermatology. , ... for skin cancer. The selective fellowship in Mohs Micrographic Surgery completed by Dr. Dorsey ...
(Date:6/25/2016)... ... 2016 , ... As a lifelong Southern Californian, Dr. Omkar Marathe earned his ... David Geffen School of Medicine at UCLA. He trained in Internal Medicine at Scripps ... in hematology/oncology at the UCLA-Olive View-Cedars Sinai program where he had the opportunity to ...
(Date:6/24/2016)... ... ... A recent article published June 14 on E Online details ... to state that individuals are now more comfortable seeking to undergo not only the ... and cheek reduction. The Los Angeles area medical group, Beverly Hills Physicians (BHP) notes ...
(Date:6/24/2016)... ... June 24, 2016 , ... The Pulmonary Hypertension Association ... it will receive two significant new grants to support its work to advance ... 25th anniversary by recognizing patients, medical professionals and scientists for their work in ...
Breaking Medicine News(10 mins):
(Date:6/26/2016)... 27, 2016  VMS Rehab Systems, Inc. ( ... whatever measures required to build a strong and stable ... currently listed on the OTC Markets-pink current trading platform. ... CEO, "We are seeing an anomaly in market trading ... only by the Company, but shareholders and market players ...
(Date:6/24/2016)... , June 24, 2016  Global Blood ... biopharmaceutical company developing novel therapeutics for the treatment ... today announced the closing of its previously announced ... stock, at the public offering price of $18.75 ... offering were offered by GBT. GBT estimates net ...
(Date:6/24/2016)... 2016 The Academy of Managed Care Pharmacy ... that would allow biopharmaceutical companies to more easily share ... formulary and coverage decisions, a move that addresses the ... The recommendations address restrictions in the sharing ... drug label, a prohibition that hinders decision makers from ...
Breaking Medicine Technology: