How embryo movement stimulates joint formation

May 18, 2009

A new study uncovers a molecular mechanism that explains why joints fail to develop in embryos with paralyzed limbs. The research, published by Cell Press in the May issue of the journal Developmental Cell, answers a longstanding question about the influence of muscle activity on developing joints and underscores the critical contribution of movement to regulation of a signaling pathway that is important during development and beyond.

Joint development requires changes in that "commit" cells to becoming part of the developing joint and distinguish them from the surrounding cartilage tissue. Previous research has shown that the Wnt/?-catenin signaling pathway plays a key role in maintaining this joint cell fate and preventing joint cells from differentiating into cartilage.

It is also clear that muscle contraction is involved in proper formation of the skeleton. "We have known for over a century that embryonic movement is intimately involved in development of the joints. However, the precise mechanism by which active musculature regulates joint formation has remained elusive," explains senior study author Dr. Elazar Zelzer from the Department of at the Weizmann Institute of Science in Israel.

Dr. Zelzer and colleagues confirmed that the normal process of joint formation was disrupted in mouse models that lacked limb musculature or muscle contractility. They then noted that cells at the presumptive joint sites ceased to express classical joint markers and instead followed a pathway for developing cartilage. Local loss of β-catenin activity explained why the joints failed to form.

"Prior to the current study, the mechanisms that underlie the contribution of movement to the process of joint development were mostly missing," says Dr. Zelzer. "Our findings show that muscle contraction is necessary to maintain joint progenitor cell fate and explain how and why movement-induced mechanical stimuli play a key role during development."

Importantly, the current results also establish joint formation as a context in which to study mechanical regulation of the Wnt/?-catenin signaling more generally. The ability to respond to mechanical stimuli may also affect β-catenin-related tumorigenesis in disorders such as colon cancer.

Source: Cell Press (news : web)

Explore further: A real-time tracking system developed to monitor dangerous bacteria inside the body

add to favorites email to friend print save as pdf

Related Stories

Lithium and bone healing

Jul 30, 2007

Researchers have described a novel molecular pathway that may have a critical role in bone healing and have suggested that lithium, which affects this pathway, has the potential to improve fracture healing.

Progress toward new therapies for coronary artery disease

Nov 08, 2007

Coronary artery disease is a leading cause of mortality in Western countries. It cannot be cured. Recent research, led by Pilar Ruiz-Lozano, Ph.D., at the Burnham Institute for Medical Research, may lead to new therapies ...

Building the blood-brain barrier

Oct 27, 2008

Construction of the brain's border fence is supervised by Wnt/b-catenin signaling, report Liebner et al. in The Journal of Cell Biology.

Stem cell research uncovers mechanism for type 2 diabetes

Feb 12, 2009

Taking clues from their stem cell research, investigators at the University of California San Diego (UC San Diego) and Burnham Institute for Medical Research (Burnham) have discovered that a signaling pathway involved in ...

Recommended for you

Cause of ageing remains elusive

14 hours ago

A report by Chinese researchers in the journal Nature a few months ago was a small sensation: they appeared to have found the cause for why organisms age. An international team of scientists, headed by the ...

Newly discovered bacterial defence mechanism in the lungs

16 hours ago

A new study from Karolinska Institutet presents a previously unknown immunological mechanism that protects us against bacterial infections in the lungs. The study is being published in the American Journal of Respiratory an ...

User comments : 0