Extraction of Ancient Insect DNA from Copal!

 

This article discusses the ability to extract ancient DNA from insects trapped in copal. It tests the hypothesis of whether or not aDNA (ancient DNA) could possibly be preserved over such an extensive period of time. They were able to extract endogenous DNA molecules from one of the samples they analyzed, and able to make taxonomic identifications regarding the organism, though it was incredibly degraded. They did so via radiocarbon analysis. They discuss struggles regarding human DNA contamination, and how tedious the separation of modern human DNA from the aDNA was. Additionally, they discuss reasons behind why they advise against this type of analysis- it is highly destructive to the samples.

I am highly interested in the extraction, sequencing, and use of ancient DNA in modern studies. Therefore, it is not surprising that I find this article incredibly fascinating. Scientifically, I find this an incredible feat, which is primarily attributed to the fact that DNA degrades so quickly. It is absolutely insane to think that we may be able to extract ancient biomolecules, and harness the ability to not only make assumptions about ancient organisms, but also use the information gathered to make strides in modern genetic research. 

Extraction of Insect DNA From The Air!

    This article details how we have a high estimate of the total number of species on this planet. It discusses how many species we have discovered in comparison to our early highest estimates, and provides a potential solution. Our current method of identifying new species around the world is incredibly slow, only moving forward by people actively going in the field, collecting, and describing species. Additionally, rates of species discovery grow increasingly slower as the species decrease in size. However, this new form of technology would allow the capture of DNA from within the air. It costs less, and is faster than traditional sampling methods, and, additionally, can ID many species simultaneously. Airborne samples are collected using something called a liquid cyclone contraption. This pulls air into a liquid filled tube, trapping DNA fragments. This then allows for DNA extraction, amplification, and sequencing. This method is particularly efficient with insect species, which is significant because insects are the most diverse group of organisms on the planet. This article stresses how species identification is very important for conservation efforts. 

    I find this article to be incredibly interesting. As someone who actively studies insects, I feel as though this new method is far more efficient when it comes to insect identification and the identification of new insect species. it would also in theory utilize less resources, as now individuals studying the insects won't have to spend as much time in the field, therefore reducing the need for long term camping, and other resource use in the field. I can foresee some potential problems, however this is a fantastic starting point, and feels almost like the work of science fiction. I cannot wait to see where this research goes.

(Pictured is an example of a liquid cyclone separator)

Insect Genes From Microbes

A study published in the journal Cell reveals that over 1,400 genes found in 218 species of insects, including butterflies and moths, were inherited from bacteria, viruses, fungi, and plants through horizontal gene transfer (HGT) hundreds of millions of years ago. This gene transfer might have played a crucial role in insect evolution, aiding them in developing advantageous traits related to mating behavior, nutrition, growth, and adapting to environmental changes. Although HGT is common among microbes, researchers have now begun examining the phenomenon's impact between insects and other organisms. The study's authors, led by Xing-Xing Shen from Zhejiang University, collaborated with Vanderbilt University's Antonis Rokas to analyze insect genomes, revealing numerous instances of HGT events. One particular gene, found in moths and butterflies and inherited from bacteria, was linked to viable egg production and male courtship behavior. The researchers intend to conduct further studies to understand the gene's mechanisms and its potential application in pest control.

Ants Prove To Be Crucial In Tracing the Evolution of Social Insects

        One may often wonder what has led specific organisms to give up a solitary existence and instead opt to a communal lifestyle, for a colonial way of life often comes with a system of division between reproducers and laborers. Evolutionary Biologist, Dr. Romain Libbrecht, and his team of researchers from Rockefeller University in New York City have decided to investigate the essential question as to what dictates one's role within society and where there are distinct differences between a queen or laborer in eusocial species.

       To their surprise, the research team soon discovered that a single gene called insulin-like peptide 2 (ILP2) was responsible for this differentiation after studying seven different ant species. This gene is most likely activated by increased nutrient levels and once activated it is responsible for "stimulat[ing] the ovaries and trigger[ing] reproduction" (1). In order to further explore what mechanisms fuel the division of labor in these types of societies, the researchers took a closer look at the ant species, Ooceraea biroi. This species was chosen for two main reasons. First off, no queens exist simply female workers. However, the female workers are allowed to reproduce and do so through parthenogenesis, which is the process of making an exact copy of one's self.  Secondly, this species has a very specific cycle when it comes to balancing work and reproduction. An eighteen-day period is allotted to laying eggs followed by a sixteen-day period which is used for collecting food and feeding the newborn larva.

      The researchers purposely broke the cycle by injecting synthesized ILP2 into the ants causing them to lay eggs during the period in which they were supposed to be caring for the young. In doing so, the researchers are able to witness a change in the ant's behavior and physiology. The organism attempts to accommodate for larva during the egg-laying period and will ultimately end the reproduction faster in order to move onto caring for the newborns.

After reading this article, I have gained a newfound knowledge in what determines an insect's role within their colony. Since ILP2 is more active in highly nourished individuals it supports the logic as to why the queen or reproducers of the colony are often larger and get the first priority when it comes maintaining a sufficient nutrients supply for their role is crucial to the survival of the entire colony. To extend this research further I certainly feel as if the effect of this gene in humans should be investigated for it may prove useful at fertility doctors.

Resource:
https://www.sciencedaily.com/releases/2018/09/180907110434.htm

Evolution of Herbivorous Insects

Researchers at the University of Arizona examined how evolution has affected the transition of non-plant diet insects to herbivores. This is an interesting topic to geneticists because herbivorous insect species make up half of all known insect species, but only one-third evolved from a non-plant diet. Benjamin Goldman-Huertas, lead author of the paper, explained how the transition to herbivory happened infrequently, but when it did, led to intense speciation. The reason for this infrequent switch is due to plants' defense system of tough outer skin and indigestible or toxic tissues. This explains why most plant-eating insects are parasites which use the plant they feed on to lay their eggs and leave their larvae. In their study, they used the Drosophila melanogaster, fruit fly, and it's close relative fly species the Scaptomyza flava to test the hypothesis that this transition needed drastic changes in behavior, which then required remodeling of the genetic and neurological processes of those behaviors. The Scaptomyza flava do not waste their time flying around rotting fruit like fruit flies; instead females seek out healthy plants, drink the plant juice, and then lay their eggs which then, as larvae, eat their way through the leaves leaving and possibly killing the plant.

Goldman-Huertas worked with John Hildebrand, a Regents' Professor in the UA's Department of Neuroscience, to measure electrical responses in the insects' antennae generated by olfactory receptors when the insects were presented with different scents. The smell of yeast, which grows on rotting fruit, is a huge attractant to Drosophila melanogaster, but left the Scaptomyza flava without a response. Conversely, only the Scaptomyza flava responded to the scent of freshly cut grass. They found a group of olfactory receptor genes that had undergone a disproportionate amount of sequence change suggesting Darwinian evolution has changed the function of these genes.

Overall, I found this article intriguing due to the work with the Drosophila melanogaster which is the species of fly we are currently using in lab. Also, it is interesting to note how, through evolution, the function of individual genes may change. The importance of this is highlighted in the end of the article as well, since it explains how gaining of this knowledge could help to stop the negative impacts of the Scaptomyza flava on canola in Europe and mustard plants in New Zealand. Furthermore, this could go on to explain how and why the Anopheles mosquitoes that spread malaria started feeding on humans and could lead to possible methods of increased prevention.



Original Article: http://www.sciencedaily.com/releases/2015/01/150129170402.htm

Patent Awarded for Genetics-Based Nanotechnology Against Mosquitoes

            The Mosquito (Culiseta longiareolata) is arguably the most annoying insect humans interact with on a regular basis. During the mild weather of spring and the sweltering heat of summer, mosquitos swarm their victims in droves, surreptitiously sucking blood from a choice of several animal species. In addition to this grievance, mosquitos are primary carriers of HIV, Malaria and West Nile virus in the Eastern hemisphere. However, these petty creatures may no longer pose such a significant threat to overall health and quality of life in the near future.
            Researchers at Kansas State University have developed a method of keeping mosquitos and even other annoying insects at bay from their victims. It is United States patent number 8,841,272, formally called "Double-stranded RNA Based Nanoparticles for Insect Gene Silencing." This technique uses genetics-based technology to kill these insects with minimal repercussions, especially upon juxtaposing alternative methods such as using pesticides that have detrimental effects on the environment. Kun Yan Zhu, professor of entomology and Xin Zhang, a research associate in the Division of Biology, developed the technology. They said it utilizes nanoparticles comprised of a non-toxic, biodegradable polymer matrix and insect derived double-stranded ribonucleic acid, or dsRNA. The purpose of this process would be to interfere with RNA interference, or RNAi, to destroy the genetic code of an insect in a specific DNA sequence.

            This technology could be the near perfect solution for the inundation of these types of insects, particularly in Africa. Once ingested the nanoparticles act as a "Trojan horse," releasing loosely bound dsRNA into the insect gut. This subsequently triggers a genetic chain reaction, thus destroying messenger RNA and killing the insect. If these studies ultimately come to fruition, this method of killing insects could save hundreds of thousands of lives per year. 

Main article: http://phys.org/news/2014-11-patent-awarded-genetics-based-nanotechnology-mosquitoes.html

More Information: http://phys.org/news/2014-10-protein-insect-blood-power-pests.html#inlRlv

Sequencing of the Mountain Pine Beetle’s Genome

Science Daily published an article entitled “Researchers Help Unlock Pine Beetle's Pandora's Box” by 20 researchers from British Columbia (Christopher I. Keeling, Macaire Yuen, Nancy Y. Liao, T. Roderick Docking, Simon K. Chan, Greg A. Taylor, Diana L. Palmquist, Shaun D. Jackman, Anh Nguyen, Maria Li, Hannah Henderson, Jasmine K. Janes, Yongjun Zhao, Pawan Pandoh, Richard Moore, Felix Sperling, Dezene Huber, Inanc Birol, Stephen Jones, and Joerg Bohlmann). The researchers identified the sequencing of the mountain pine beetle’s genome in order to determine beetle population changes during infestation periods. In addition, a bacterial gene has been identified in the beetle’s genome that codes for an enzyme that digests sugar which may be aid in the digestion of wood. This information will assist authorities of British Columbia to limit the destruction of the forests by planning for future outbreaks. Currently, it is estimated that the mountain pine beetle has destroyed thousands of acres of forest in western North America.
I hope the research continues and an environmentally safe deterrent is identified to eradicate these pests. It is my understanding that the only treatment is an insecticide spray and it must be applied to the trees prior to infestation.
Article Link: http://www.sciencedaily.com/releases/2013/04/130405155832.htm

http://www.pc.gc.ca/eng/docs/v-g/dpp-mpb/sec4.aspx