Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sensing Tension: Molecular Motor Works By Detecting Minute Changes in Force

11.07.2008
Researchers at the University of Pennsylvania School of Medicine discovered that the activity of a specific family of nanometer-sized molecular motors called myosin-I is regulated by force.

The motor puts tension on cellular springs that allow vibrations to be detected within the body. This finely tuned regulation has important implications for understanding a wide variety of basic cellular processes, including hearing and balance and glucose uptake in response to insulin. The findings appear in the most recent issue of Science.

“This is the first demonstration that myosin-I shows such dramatic sensitivity to tension,” says senior author E. Michael Ostap, Ph.D., Associate Director, Pennsylvania Muscle Institute and Associate Professor of Physiology. “It is surprising that a molecular motor can sense such small changes in force.”

Myosin-I is a biological motor that uses the chemical energy made by cells to ferry proteins within cells and to generate force, powering the movement of molecular cargos in nearly all cells.

... more about:
»Molecular »Myosin »Protein

In two specific cases, myosin I puts tension on the specialized spring-like structures in human ears that enable hearing and maintenance of balance, and also has a role in delivering the proteins that pump glucose into cells in response to insulin. “However, why a tension-sensing molecular motor is needed for this function is unknown,” says Ostap.

In collaboration with Henry Shuman, PhD, Associate Professor of Physiology, the research team used optical tweezers -- a combination focused laser beam and microscope, of sorts -- to measure incredibly small forces and movements (on the piconewton and nanometer level) to discover that myosin I motors are regulated by force. The motors pull on their cellular cargos until a certain tension is attained, after which they stop moving, but will hold the tension. If something happens in the cell to decrease this tension, the motor will restart its activity and will restore the lost tension.

Myosins use the energy from ATP to generate force and motion. Humans have 40 myosin genes that sort into 12 myosin families. Members of the myosin family have been found in every type of cell researchers have examined. The Ostap lab is investigating the biochemical properties of several members of the myosin family to better understand movement in cells, which is important in development, wound healing, the immune response, and the spread of cancer, among other functions. These new findings shed light on the role of myosin I in cells, supporting the notion that this molecular motor is more important in generating and sustaining tension rather than transporting protein cargo.

The research team will now apply these results to better understand how cells use these tension sensors to carry out their physiological functions.

This research was supported by the National Institute of General Medical Sciences and the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

PENN Medicine is a $3.5 billion enterprise dedicated to the related missions of medical education, biomedical research, and excellence in patient care. PENN Medicine consists of the University of Pennsylvania School of Medicine (founded in 1765 as the nation's first medical school) and the University of Pennsylvania Health System.

Penn's School of Medicine is currently ranked #4 in the nation in U.S.News & World Report's survey of top research-oriented medical schools; and, according to most recent data from the National Institutes of Health, received over $379 million in NIH research funds in the 2006 fiscal year. Supporting 1,400 fulltime faculty and 700 students, the School of Medicine is recognized worldwide for its superior education and training of the next generation of physician-scientists and leaders of academic medicine.

The University of Pennsylvania Health System includes three hospitals — its flagship hospital, the Hospital of the University of Pennsylvania, rated one of the nation’s “Honor Roll” hospitals by U.S.News & World Report; Pennsylvania Hospital, the nation's first hospital; and Penn Presbyterian Medical Center — a faculty practice plan; a primary-care provider network; two multispecialty satellite facilities; and home care and hospice.

Karen Kreeger | Newswise Science News
Further information:
http://www.uphs.upenn.edu

Further reports about: Molecular Myosin Protein

More articles from Life Sciences:

nachricht New eDNA technology used to quickly assess coral reefs
18.04.2019 | University of Hawaii at Manoa

nachricht New automated biological-sample analysis systems to accelerate disease detection
18.04.2019 | Polytechnique Montréal

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter

  • Coolest and smallest star to produce a superflare found
  • Star is a tenth of the radius of our Sun
  • Researchers led by University of Warwick could only see...

Im Focus: Quantum simulation more stable than expected

A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.

Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...

Im Focus: Largest, fastest array of microscopic 'traffic cops' for optical communications

The technology could revolutionize how information travels through data centers and artificial intelligence networks

Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...

Im Focus: A long-distance relationship in femtoseconds

Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.

Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...

Im Focus: Researchers 3D print metamaterials with novel optical properties

Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna

A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

Fraunhofer FHR at the IEEE Radar Conference 2019 in Boston, USA

09.04.2019 | Event News

 
Latest News

New automated biological-sample analysis systems to accelerate disease detection

18.04.2019 | Life Sciences

Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

18.04.2019 | Physics and Astronomy

New eDNA technology used to quickly assess coral reefs

18.04.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>