the ability to move An essential part of everyday life. The musculoskeletal or musculoskeletal system The body is made up of muscles, bones, tendons, ligaments, joints, cartilage, and other connective tissues. loss of motor function Illness or injury can result in a lifelong disability. In a rapidly aging society, maintaining and improving motor function can be a major challenge for many people.
But there are ways to overcome engine malfunction. as such molecular biologists And the orthopedic surgeons Those who study the locomotor system, we believe that a key part of it has been underestimated – the tendons.
the strings It is a hard tissue that connects muscle to bone. The tendons are what allow kangaroo To jump more than 25 feet (7.62 meters) and run up to 40 mph (64 km/h). While their leg muscles are small, the kangaroo’s long and highly developed tendons act like powerful springs. People can also jump higher if they squat first because of their tendons Flexible Energy Storage Which helps push them to the top.
In our research, we found that the presence of A specific protein in the tendons It plays a key role in how tendons heal – and a genetic mutation in this protein may also improve athletic performance.
Learn about tendon proteins
Likewise, developing treatments for tendon injuries has been challenging. One reason is that proteins that control genes instruct the body to make tendons, called transcription factorsis unknown.
To identify these proteins, we Create a catalog of the 1,600 transcription factors in the human body. Based on this catalog, we examined which genes were active in the Achilles tendon of transgenic mice and found that a protein called Mkx was a transcription factor central to tendon health.
Researchers have long considered tendons to be inert tissue, unable to contract as well as muscles. But we found out with our colleague, Erdem PatabutianThe Got the nobal giftthis specific protein on the surface of tendon cells, Piezo1, can sense when the tendon engages in moderate exercise and stimulates the transcription factor Mkx.
The discovery of Piezo1’s role in touch perception earned the 2021 Nobel Prize in Physiology or Medicine.
Piezo1 and sports performance
We then wondered what role Piezo1 plays in athletic performance. We were particularly interested in a Piezo1 variant called E756del, which is found in the vicinity One third of people of African descent It is believed to play a potential role in How can people jump.
We therefore genetically engineered mice to produce a mouse equivalent version of Piezo1 E756del proteins throughout the body and then Test their performance In various physical activities, including long jump and running on a treadmill. Surprisingly, we found that mice with E756del proteins were able to jump 1.6 times more distance without training than mice without E756del proteins. Mice with Piezo1 in their tendons were also able to run about 1.2 times faster than those without Piezo1.
To determine which part of the body was producing this jumping ability, we next generated mice that produced Piezo1 proteins either in their muscles or in their tendons. The results were even more surprising: mice with Piezo1 in their tendons improved just as well as mice with Piezo1 in their tendons. Mice with only Piezo1 in their muscles, however, had no improvement in jumping ability.
We then decided to test the role of Piezo1 in human athletic performance. In cooperation with Athlum Consortium, an international organization for sports genomics, we compared the prevalence of the gene encoding E756del in 91 Jamaican Olympic-level runners and 108 in the general population of Jamaica. We found that 54 percent of Jamaican runners had an active E756del gene, compared to only about 30 percent of the general population.
Our findings show that altering a single protein, in this case, E756del, could play a role in athletic performance. Additional research on tendons and other parts of human motor systems could help improve treatments for diseases of the musculoskeletal system.