Scientists Discover Gene Affecting Embryos in Insect Models

Notre Dame College student scientists and a faculty member have identified a gene likely responsible for proper embryo production in fruit flies.

Fruit FliesTheir findings regarding the function of the previously unstudied CG15436—now called the Hunchback of Notre Dame College (hndc)—gene gives insight into normal egg production due to the similarities between the DNA of fruit flies and more complex biological organisms.

The gene’s moniker is born of its apparent link to abdominal formation as well as embryo production and recognizes the home institution of its founders, Kristopher Trahan ’13, biology major, and M. Logan Johnson, Ph.D., assistant professor of biology.

As part of a class project with Johnson, Trahan and other students discovered with one copy of the hndc gene removed, and while controlling for heat, female fruit flies produced one-third fewer embryos. When both copies of the gene were removed, embryo production was reduced by two-thirds.

When the scientists increased the temperature at which the specimens were kept from 20 degrees Celsius (68 degrees Fahrenheit) to 30 degrees Celsius (86 degrees Fahrenheit), embryo production completely stopped—whether one or two copies of the gene were absent.

“Research has shown ovaries in biological organisms with genes absent may be overly sensitive to other influences, especially heat, so we needed to control for that influence,” Johnson said.

Furthermore, in fruit flies with the hndc gene removed, the outer layer of the dorsal abdomen, which should stretch across the body, was split in half or half was completely absent. According to the scientists, this may suggest the cells in the tissue surrounding the embryos may be the cause of the decline of embryo production in the absence of the gene.

“This research indicates the gene involved is a regulating gene, one necessary to the development of the abdomen as well as production of embryos,” Johnson said.

Trahan was selected to present and to publish his study, “CG15436, a Previously Unstudied Drosophila Melanogaster Gene, Participates in Abdominal Formation and Maintenance of Embryo Production,” through the Ohio Academy of Science.

The project was funded with a grant from the All Life Foundation of Columbus, Ohio.

“Research like this is a teaching tool, as well as work that contributes to the larger scientific body of knowledge in genetics,” Johnson said. “Encouraging students to conduct scholarship in a lab provides them real world experience and helps them learn firsthand different techniques and resources used in the processes of science.”

Trahan, who graduated this spring, has been accepted straight into a doctorate program at the University of Texas medical branch in Galveston.

hndc is one of eight different genes isolated and removed from fruit flies by eight students in Johnson’s development biology course this spring. All eight genes were targeted for their transcription factor, their likelihood of regulating other genes, and because they were previously unstudied, Johnson said.

A research project on gene CG17568 in fruit flies by senior Eric Krolik ’13 also was selected for inclusion in the Ohio Academy of Science 2013 annual meeting at the University of Findlay in Ohio.

Krolik discovered no observable change in the specimens when copies of this gene were removed.

E.g., 06/23/19
E.g., 06/23/19