Student and professor team up in genetics research

In Dr. Kevin Militello's lab, an island countertop crowded by glassware and scientific instruments, labels and notes provides a common space for students to work on their research. But Gretchen Kelly, a senior biology major doing research in the lab, doesn't mind the close quarters.

"I love the setup. We can all work around each other," she said. For Kelly, doing scientific research at Geneseo hasn't just been about her experimental work in epigenetics. It's also about personal growth and perseverance.

"It's really helped me a lot," she said. "It's just a different way of thinking. You don't sit in a class for 50 minutes. This is just me, learning, and being interested in science. It's very independent. You have to teach yourself how to be diligent." But as independent as research can seem, Kelly is quick to acknowledge how much she owes her advisor and the other students who work in the lab.

"I came to Dr. Militello over the summer. I really loved his genetics class when I had him last Spring, and I asked, 'Do you think I could get into your lab?' I just wanted to do research and he said, 'Yeah, come on in.' This is a new project to [Militello]. He thought of this one, he thought of me, and we sort of developed it together."

Kelly works with Militello in epigenetics, a developing field of genetics. Genetic traits are determined by a sequence of nucleotide bases, sometimes referred to as the genetic code or genome of an organism. But researchers are finding that genetic expression depends on more than just the genetic code. Other factors, such as methylation, can have a significant impact on genetic traits.

Methylation affects DNA expression by adding a methyl group to certain places in the genetic code. This can provide a site on the DNA for interaction with enzymes, which can alter or silence gene expression. Methylation of human DNA is fairly well understood, but the role of a certain type of methylation in E. coli is currently unknown.

Normally, methylation in E. coli provides a defense mechanism for the E. coli. Each methylase, an enzyme that methylates DNA, works to stop a corresponding restriction enzyme from cutting the DNA at that point, which would damage the organism. Methylases and restriction enzymes usually come in complimentary pairs.

But Kelly and Militello are investigating a methylase that doesn't have a complimentary enzyme, an "orphan methylase" with no known function. Interestingly, this methylase has been present in every field sample, indicating that although the function isn't known, the pathway is essential.

"The next step," Kelly said, "is to determine the role that [methylation] is playing. We are going to do an antibody test to detect methylation…amplify the gene and get a [genetic] sequence."

Kelly will be giving a talk on her research, "Measuring Cytosine DNA Methylation in Escherichia coli Field Isolates" on G.R.E.A.T. Day on April 17.