Reducing Levels of Neuropeptide Natalisn Can Lower Sexual Activity in Insects, Study Finds

Researchers have found that lowering the levels of neuropeptide natalisn can reduce reproductive ability of insects. The main implication of the study is that controlling natalisn can help curb the population of insects. It could pave the way for a new, efficient and environmentally safe pest management system.

The study on natalisin was carried out by researchers at Kansas State University along with their colleagues at the Institute of Science and Technology in South Korea, Slovak Academy of Sciences in Slovakia and Korea University in South Korea. A neuropeptide is a short chain of amino acids that is used by neurons to communicate with each other.

The team was the first to find and name the unique neuropeptide- natalisn- that controls sexual desire in insects and arthropods.

 "Natalisin is unique to insects and arthropods and has evolved with them. It appears to be related to a neuropeptide called tachykinin that is in mammals and invertebrates. While tachykinin is involved with various biological processes, including the control of blood flow in mammals, natalisin is linked to reproductive function and mating behavior in insects and arthropods," said Yoonseong Park, professor of entomology at Kansas State University.

Apart from managing the population of insects, the study can also help other researchers understand the biology of the common fruit-fly, which is used in many scientific studies.

In the study, researchers from participating institutions looked at the activity of natalisn in three insects; fruit flies, red flour beetles and silk moths.

Researchers found that natalisn is expressed in three to four neurons in all insects. They then used a tool called RNA interference, or RNAi to knock-off the genes that code for the peptide and then see the effects of the silenced gene on the insects.

Reduced levels of natalisn led to reduced sexual activity in the insects, researchers reported.

"For example, we saw that knocking out the natalisin in the fruit fly makes them unable to mate," Park said in a news release. "The female is too busy grooming her body for the male to approach her. The male doesn't send a strong enough signal to the female to get her attention. We're not sure if that's because the male can't really smell her or because he is not developed enough to signal her."

The study is published in the journal Proceedings of the National Academy of Sciences.