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Environmental Factor

Environmental Factor

Your Online Source for NIEHS News

September 2017

NIEHS trainee Sara Andres transitions to academia

The McMaster University assistant professor will use her expertise in DNA repair to study antibiotic resistance in bacteria.

In August, former NIEHS visiting fellow Sara Andres, Ph.D., started her own lab at McMaster University in Canada as an assistant professor in the Department of Biochemistry and Biomedical Sciences.

Groundbreaking research on Ctp1

At NIEHS, Andres worked in the Structural Cell Biology Group, headed by Scott Williams, Ph.D. She focused on understanding the molecular basis for the function of a protein in Schizosaccharomyces pombe yeast. The protein, called Ctp1, plays a critical role in initiating repair of DNA double-strand breaks.

“Studying the Ctp1 protein in model systems such as yeast can provide insight into the disease mechanism of Seckel and Jawad syndrome — two genetic diseases caused by mutations to the human homolog of Ctp1,” she explained. The two diseases are rare developmental disorders characterized by microcephaly and dwarfism.

Her work resulted in the first molecular structures of Ctp1 and clarified previously unknown functions of this protein. These findings were published in the journal Nature Structural and Molecular Biology. In addition, Andres was recognized for her outstanding work with a new investigator best paper award from the Environmental Mutagenesis and Genomics Society.

"She has seamlessly fused molecular structural dissections with biochemistry and phenotypic analyses in model systems (yeasts),” Williams said. “In my view, Dr. Andres has the right stuff, and we expect great things from Sara and her new laboratory," he added.

Beyond the bench

In addition to bench work, Andres participated in the Genome Integrity and Structural Biology Laboratory’s Trainees Action Committee (TAC), collaborated with other research groups, and attended workshops. She found one course, the management boot camp, particularly helpful. "It greatly contributed to helping me transition to operating my own research lab," she said.

Her work with TAC went beyond attending meetings. "I took on the role of TAC chair to gain experience as a manager, as well as to better learn how to balance administrative work with my science, knowing that I wanted a career in academia."

Moving forward

Andres has shifted her work from yeast to bacteria, but is still interested in the field of DNA repair. "My goal is to understand the molecular mechanisms of the repair pathways and exploit them for new therapeutic strategies targeting pathogenic bacteria, to help combat the continual challenge of antimicrobial resistance," she explained.

“Seventy-five percent of my time is dedicated to research, and the rest [is] focused on teaching and administrative work," Andres said.

Andres shared some advice for fellows looking to transition to academia. "Take advantage of all the resources available to you when working at NIEHS and within the Research Triangle — from the top-notch scientists and research facilities, to the opportunities provided by the Office of Fellows’ Career Development, because these will provide you with the tools you need to get to your next career goal."

Andres SN, Appel CD, Westmoreland JW, Williams JS, Nguyen Y, Robertson PD, Resnick MA, Williams RS. 2015. Tetrameric Ctp1 coordinates DNA binding and DNA bridging in DNA double-strand-break repair. Nat Struct Mol Biol 22(2):158–166.

Andres SN, Schellenberg MJ, Wallace BD, Tumbale P, Williams RS. 2015. Recognition and repair of chemically heterogeneous structures at DNA ends. Environ Mol Mutagen 56(1):1–21.

(Salahuddin Syed, Ph.D., is an Intramural Research Training Award fellow in the NIEHS DNA Replication Fidelity Group.)

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