Tendons shape bones during embryonic development

December 14, 2009

In all vertebrates, including humans, bones, muscles and tendons work together to give the skeleton its characteristic balance of stability and movement. Now, new research uncovers a previously unrecognized interaction between tendons, which connect muscles to bones, and the developing embryonic skeleton. This study, published by Cell Press in the December 15th issue of the journal Developmental Cell, demonstrates that tendons drive the development of specific bone features that are needed for a strong skeletal system.

"Our skeleton with its bones, joints, and muscle attachments serves us so well in our daily lives that we hardly pay attention to this extraordinary system," says senior study author, Dr. Elazar Zelzer from the Weizmann Institute of Science in Rehovot, Israel. "Although previous research has uncovered mechanisms that contribute to the development and growth of each issue composing this complex and wonderfully adaptable organ system, specific interactions between bones, muscles and tendons that drive the ordered assembly of the musculoskeletal system are not fully understood."

Dr. Zelzer and colleagues were interested in uncovering how "bone ridges" form. Bone ridges are knobby, thickened areas of bone that can be found wherever tendons are attached. These reinforced sections of bone are important anchoring points for connecting bones to muscles, and strong attachment at these sites enables the skeleton to cope with mechanical stresses exerted by the muscles.

While studying mouse embryos, the researchers discovered that tendons control the formation their own bone ridges through a two-stage process. First, tendons initiate outgrowth of the bone ridge by secreting a protein (BMP4) that promotes bone formation. Then, during the second stage, muscle activity helps to promote further bone growth and set the final size of the bone ridge.

Taken together, the results demonstrate that tendons are needed for bone ridge patterning. "These findings provide a new perspective on the regulation of skeletogenesis in the context of the musculoskeletal system and shed light on a specific mechanism that underlies the assembly of this system," concludes Dr. Zelzer.
-end-
The researchers include Einat Blitz, Weizmann Institute of Science, Rehovot, Israel; Sergey Viukov, Weizmann Institute of Science, Rehovot, Israel; Amnon Sharir, Weizmann Institute of Science, Rehovot, Israel, The Hebrew University of Jerusalem, Rehovot, Israel; Yulia Shwartz, Weizmann Institute of Science, Rehovot, Israel; Jenna L. Galloway, Harvard Medical School, Boston, MA; Brian A. Pryce, Shriners Hospital for Children, Research Division, Portland, OR; Randy L. Johnson, University of Texas, MD Anderson Cancer Center, Houston, TX; Clifford J. Tabin, Harvard Medical School, Boston, MA; Ronen Schweitzer, Shriners Hospital for Children, Research Division, Portland, OR; and Elazar Zelzer, Weizmann Institute of Science, Rehovot, Israel.

Cell Press

Related Muscles Articles from Brightsurf:

Muscles support a strong immune system
In the fight against cancer or chronic infections, the immune system must be active over long periods of time.

The death marker protein cleans up your muscles after exercise
Researchers at the University of Copenhagen's Department of Nutrition, Exercise and Sports have demonstrated that physical activity prompts a clean-up of muscles as the protein Ubiquitin tags onto worn-out proteins, causing them to be degraded.

Brain cells protect muscles from wasting away
Several processes in the roundworm C. elegans boost the stress response in cells, incidentally making worms resistant to a high-fat diet and extending their lifespan.

Study of cardiac muscles in flies might help you keep your heart young
Iowa State University scientists restored the function of heart muscles in aging fruit flies, according to a newly published study.

A better understanding of soft artificial muscles
Artificial muscles will power the soft robots and wearable devices of the future.

RoboBee powered by soft muscles
Harvard researchers have developed a resilient RoboBee powered by soft artificial muscles that can crash into walls, fall onto the floor, and collide with other RoboBees without being damaged.

How cancer breaks down your muscles
A solid tumor can cause muscle cells in the body to self-destruct.

Artificial muscles bloom, dance, and wave
Researchers from KAIST have developed an ultrathin, artificial muscle for soft robotics.

One or the other: Why strength training might come at the expense of endurance muscles
The neurotransmitter brain-derived neurotrophic factor (BDNF) acts in the muscle, so that during strength training endurance muscle fiber number is decreased.

Sheaths drive powerful new artificial muscles
Over the last 15 years, researchers at The University of Texas at Dallas and their international colleagues have invented several types of strong, powerful artificial muscles using materials ranging from high-tech carbon nanotubes (CNTs) to ordinary fishing line.

Read More: Muscles News and Muscles Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.