Is the worm the key to healthy aging?
Unfortunately, the ever-increasing life expectancy in recent decades has not led to an increase in the health or quality of life of people in old age to the same extent. That is why researchers are looking for ways to improve the quality of life in old age. The newly discovered gene in worms can now give answers.
A recent study by the Okinawa Institute of Science and Technology (OIST) revealed a gene in a worm that is associated with the healthy aging of the C. elegans roundworm. The results of the study were published in the English journal "G3: genes, genomes, genetics".
Movement in old age is an indicator of health
In the C. elegans roundworm, the elpc-2 gene was identified, which plays an important role in maintaining health status as the worm ages. Worms with defects in this gene show movement disorders in old age. Movement in old age is an indicator of the health of people and worms. Researchers report that this gene is preserved in humans. “When we get older, some people retain full mobility, others do not, and we want to understand the genetic causes,” explains study author Dr. Kazuto Kawamura of the Okinawa Institute of Science and Technology in a press release.
C. elegans is good for studying aging
This gene is one of many other genes that play an important role in healthy aging. A new experimental approach allows us to study hundreds of worms at the same time, which may be useful for other studies in the future. The elpc-2 gene is expressed throughout the body of C. elegans. It plays an important role in the ability to move as the worms get older. C. elegans is a useful model for studying aging, since worms have a short lifespan and are easy to manipulate in the laboratory. Researchers inserted random mutations into the worms' genome. By studying the offspring of mutant worms, it was possible to analyze which mutations affected health.
How was the experiment organized?
Researchers investigated whether organisms could retain their ability to move to a food source as they mature. To do this, the worms were placed in the middle of the bowl, and the food – on the edge of the bowl. Worms move by nature to food, until their movement is disturbed. All worms that did not reach the feed on the first day were removed from the experiment. The authors wanted to find out how the ability to exercise decreases with age. The remaining worms were re-checked when they got older using the same approach. In this later test, several worms with movement disorders were identified. They were then sequenced, and their DNA was compared to that of a normal worm, to find mutations and identify the responsible genes.
What is the complex Elongator?
Creating hundreds of random mutations was not very difficult for researchers. More problematic is finding out which mutation is responsible for influencing the ability to move. However, with the new approach of worms crawling to a food source on the edge of the shell, the mobility of hundreds of worms can be tested at the same time, the authors explain. Thus, the researchers identified the elpc-2 gene and its role in the health of worms. The gene encodes a portion of the so-called elongator complex, which performs many important functions, including controlling the proper folding of proteins. Some of these proteins may, in turn, play a role in movement. Worms with the damaged elpc-2 gene did not have a functioning complex of elongators, which explains why the movement was disturbed. To confirm this, the researchers introduced a copy of the gene to these worms, and the movement was restored.
Further research will take place in Germany.
Interestingly, other genes were identified that also had a strong effect on the health, but not on the life expectancy of animals, the authors report. In other words, the underlying mutations did not have a significant effect on the life span of the worm, but on how it moves. This shows that, although health and longevity are the same, the genetic basis is different, the researchers explain. In the future, author Kawamura wants to explore other genes that are important for healthy aging. “As soon as we get a more complete picture of the genes involved, we can begin to manipulate them in order to improve health, first with C. elegans and, perhaps, someday with people,” the author says. Now Kawamura will continue working on C. elegans at the prestigious Max Planck Institute for Aging Biology in Germany. (How)
- Kazuto Kawamura, Ichiro N. Maruyama: Direct genetic screening for Caenorhabditis elegans Mutants with shortened motor health, in G3: Genes, Genomes, Genetics (request: July 14, 2009), G3: Genes, Genomes, Genetics
- New gene is associated with healthy aging in worms, Okinawa Science and Technology Institute (request: July 14, 2009), OIST