Desiree Mills is a junior Biology major at Tougaloo College that has been performing academic-year biomedical since joining the laboratory of Dr. Scoty Hearst in 2018. “Getting the opportunity to work with Dr. Hearst on his research, which is funded by Mississippi INBRE, has fostered a genuine interest and passion for research in me as I learn and obtain new skills while participating in a study that seeks to change neurodegenerative medicine.”


Dr. Hearst’s research investigates the role of matrix metelloproteinases (MMPs) involvement in the degradation of protein aggregates that are formed in many neurodegenerative diseases, which in addition of the protein aggregates causing neural dysfunction, the breakdown of these aggregates by MMP also increases toxicity in the affected cells, leading to neurodegeneration. Specifically, Dr. Hearst’s research, and that performed by his student researcher, Desiree Mills, has focused on the role of MMPs in metabolism of mutant ATXN1 aggregates found in the neurons of patients with the polyglutamine disease Spinocerebellar Ataxia type 1 (SCA1 disease). SCA1 is a progressive movement disorder that typically begins in early adulthood, with early signs and symptoms including problems with coordination and balance (ataxia), speech and swallowing difficulties, muscle stiffness, and weakness in the muscles that control eye movement.


Mills has been able to present her findings she has generated with Dr. Hearst with increased award recognition for her work over the past year, where she placed 5th overall for undergraduate poster presentation at the Mississippi IDeA Conference 2019, was awarded sponsorship to present her research and represent Mississippi INBRE at the Southeast Regional IDeA Conference 2019 in Lexington, KY, and even more importantly was specifically invited to present her SCA1 research at the University of Minnesota BGREAT Diversity Conference 2020 where she took first place overall for undergraduate research presentation.


“I am very proud of her. The University of Minnesota Medical School is home to one of the largest SCA1 research labs in the world and she was able to stand among their students and take 1st place,” praised Dr. Hearst.


Mills reflected on her presentation experience opportunities provided by Mississippi INBRE:

“After placing 5th at the 2019 Mississippi IDeA Conference and getting the opportunity to attend the SE Regional IDeA Conference is when I truly got the pleasure of meeting and interacting with not only members of the Mississippi INBRE team but also other student researchers. Though the trip was short the knowledge, experience and advice gained were tremendous as they pushed me to brush up on my communication skills and delivery and trained me to think quickly and critically on my feet. I left this trip much more confident in myself and my research which I believe is what aided me in preparing for the UMN BGREAT Diversity Conference where I placed 1st.”


Even more important than receiving recognition is the work that Dr. Hearst and Mills have accomplished. Like other neurodegenerative diseases such as Huntington’s disease, Alzheimer’s disease, and Parkinson’s disease which show increased MMP expression with disease involvement, Mills was able to fluorometrically confirm the colocalization of MMPs with ATXN1 aggregates in the nucleus of a SCA1 Drosophila fly model, as well as the confirmation of increased ATXN1 cleavage with increased MMP expression, indicating ATXN1 serves as a substrate of MMPs. They concluded, “MMPs may play an important role in ATXN1 solubility and enhance the SCA1 disease progression. We also found that dMMPs enhanced nuclear rupture and so MMPs may be toxic to neurons when expressed at high levels. Continuing this work is critical to supporting our long-term goal, which is to decipher the role of MMPs in neurodegenerative diseases using the drosophila SCA1 animal model as a model of neurodegenerative disease. Better understanding the roles of MMPs in neurodegenerative disease pathways will have a critical impact on neurodegenerative medicine.”