Fruit fly study could unlock answers to muscle illness

Fruit flies may provide some clues in the search for cures to muscle diseases, according to UNM assistant biology professor Richard Cripps.

Cripps said fruit flies, otherwise known as drosophila, have two types of muscles. They use one type of muscle for flying and the other for walking. Cripps wants to know what causes the fruit fly’s DNA to create each type of muscle. He said it is likely that a trigger protein, called a transcription agent, serves as a sort of switch that determines when a particular type of muscle cell is created.

The National Institutes of Health awarded Cripps a $1.05 million grant to look for those trigger proteins. He said it is important to learn more about the process of muscle production at the molecular level because it could help in the fight against muscle disease.

“The goal is to understand how molecular events tell a cell what type of muscle it will form,” Cripps said.

He said humans, like fruit flies, have different types of muscles. According to a UNM press release, research has proven that the molecular process leading to muscle formation is similar all the way up the evolutionary ladder, from fruit flies to humans.

When asked why he works with fruit flies, Cripps said they are easy to culture and grow and the existing knowledge of their genetic structure makes the flies ideal for research about how genes are switched on and off. He also said drosophila have a short life cycle, so “you’re not waiting around forever” to see what happens.

In the pupa stage of the drosophila lifecycle, when the larva becomes a cocoon and metamorphosis occurs, the larval muscles are broken down and an entirely new set of muscles is created.

“We’re studying genes that are only expressed in the pupa stage,” Cripps said.

If Cripps is successful in finding the elusive trigger proteins, it will be another small piece in the puzzle scientists are trying to solve to better understand the causes of muscle diseases.

Cripps and his staff spend their days making genetically engineered fruit flies. The search is a slow process of elimination.

He said he fuses a piece of DNA to an easily detected gene to see if it alters the muscle development within the cocoon. If it does, he then fuses smaller and smaller pieces of DNA to the gene, in order to find out exactly which gene is being switched on. By doing this, he hopes to find the exact protein that causes the genes to produce each type of muscle cell.

Cripps, 34, was born in Nottingham, England. He received his doctorate from the University of York. He said his research experience is mostly in genetics and developmental biology, which is the study of how fertilized eggs divide and grow to give rise to organisms. He applied for the grant in July of last year. The funding is to cover a five-year period of research costs.

Cripps said there is no danger of the genetically engineered flies escaping into the environment.

“We’ve been in contact with the USDA to ensure that we’re complying with regulations,” he said.