FEB 18, 2014 12:00 AM PST

New Technique of Studying Insect Physiology Through DNA Extractions

WRITTEN BY: Jen Ellis
Grasshoppers may be a nuisance to your garden, but their voracious appetites and large numbers can cause more significant problems for farmers and ranchers by consuming cash crops as well as grasses needed to feed livestock. However, they do have a positive role to play in the ecosystem - they are a living system to recycle nutrients from decomposing plants and redeposit them in the soil. Increased understanding of the grasshopper's feeding patterns could lead to more effective methods of intervention and control with minimal damage to the overall ecosystem.

With this in mind, researchers at the University of Cincinnati developed a new method of dissection and DNA extraction to get more information about the grasshoppers than was available in previous analytical methods. Their work was summarized in Applications in Plant Sciences, and a corresponding video illustrating the dissection method is also available.

The method starts with a standard dissection kit, allowing the scientists to isolate the grasshopper guts into sections. DNA extraction removes both plant and grasshopper DNA, and then PCR (polymerase chain reaction) is used to separate and isolate the plant DNA. This method takes less than three hours and uses standard inexpensive lab equipment. It also allows sequential tracking of the grasshopper's food, since the gut sections can be independently studied.

The sequential tracking allows scientists to determine the sequence in which food was consumed and roughly estimate the time needed to digest food in each section. This allows for comparisons of the feeding habits and mechanisms between different grasshopper species and variations within species.

As an example of how the technique could be used, DNA from a specific portion of a plant chloroplast gene was amplified for feeding trial purposes on different species and ages of grasshoppers. The team found that plant tissue could be found up to 12 hours post-ingestion in adult M. femurrubrum grasshoppers and in nymphs of M. bivittatus and M. differentialis, but the larger adult M. differentialis retained plant tissue up to 22 hours post-ingestion. With this knowledge, researchers can time the dissection of future feeding experiments.

The team also discovered that M. differentialis, generally did not switch back and forth between available grasses, but ate them sequentially instead. This would indicate preferences for certain types of grasses over others. It may be possible to ultimately discover what grasses are preferred, and why, within a species - for, example, is one type of grass more readily digestible than another? If there are plants that are physiologically similar but have different preferences among the grasshoppers, can scientists use that knowledge to change the grasshoppers' habits (through such things as plant modifications or different planting patterns)?

The study has implications beyond grasshoppers, since it can be modified to study any plant-eating insect. With its simplicity, versatility, and lack of reliance on expensive laboratory equipment, we can expect this method to be used on multiple insect studies in the future, and it is likely to lead to new methods of insect population management.
About the Author
You May Also Like
JAN 09, 2020
Neuroscience
JAN 09, 2020
Why Do you Have a Higher IQ than your Grandparents?
In the 1980’s James Flynn found that on average, human intelligence quotients (IQ) increase by 3 points every 10 years. Known as the “Flynn eff...
JAN 20, 2020
Genetics & Genomics
JAN 20, 2020
Braveheart RNA Structure is Revealed For the First Time
Protein-coding genes only make up a small part of the genome. Much of the rest may contain long, non-coding RNA sequences....
MAR 03, 2020
Cell & Molecular Biology
MAR 03, 2020
New CRISPR-HOT Technique Can Color Cells and Genes
Since the CRISPR/Cas9 editing tool was developed several years ago, many scientists have modified and improved it for different applications....
MAR 04, 2020
Genetics & Genomics
MAR 04, 2020
DNA Fragments and Cartilage Recovered From 75-Million-Year-Old Dinosaur Bones
An international team of researchers has analyzed cartilage from a baby duckbilled dinosaur, and they have identified bits of preserved proteins and what seems to be chromosomes....
MAR 09, 2020
Genetics & Genomics
MAR 09, 2020
Researchers Alter How Bacteria Communicate
The bacterium Escherichia coli comes in many forms, and researchers have used a harmless strain of it to redesign how the microbes communicate....
MAR 25, 2020
Technology
MAR 25, 2020
What is eDNA?
What exactly is eDNA? It is environmental DNA that has underwent the next-generation sequencing and that has been ‘barcoded’ in a way that can ...
Loading Comments...