Join us for the Autumn CBMSS Meeting!! Dr. Lilliana Dadoshevich will be presenting her work using proteomics in pathogen spread. Please share this announcement with anyone you beleive will find it of interest!
Speaker: Dr. Lilliana Radoshevich
Title: Exploring the Role of ISGylation in Pathogen Spread using Label-free Quantitative Proteomics (abstract below).
Date: Oct 16th, 2025
Time:
Location: CSU Powerhouse Campus (follow link for map). Parking options are described here. Come early for a tour of the CSU powerhouse campus, home to the CSU Energy Insitute, and a facility dedicated to all things energy. It houses both fascinating research and hardware - you can find a virtual tour here, but you should consider coming for the in-person tour, i doubt you will regret it.
Abstract: Cells integrate signals from the extracellular milieu, survey the cytosol for pathogenic intruders and assess internal levels of damage and stress in order to survive. The transcriptional response to cellular stress has been well characterized, however changes in the post-translational landscape of the cell following stress or infection represent an exciting and understudied new frontier in biology. Ubiquitin-like modifications (UBLs) are rapid, reversible and can profoundly alter cell fate and function. Intriguingly, the majority of UBLs are involved in the cellular response to stress, in particular the response to infection, nutrient limitation, and autophagy and are dysregulated in a number of intractable human pathologies such as cancer, autoimmune disease and protein-folding disorders. My laboratory takes an interdisciplinary approach combining cutting-edge proteomics with genome editing, biochemistry and cell biology to determine fundamental properties and modes of action of understudied UBLs. As a model, we make use of infection with two intracellular bacterial pathogens: Listeria monocytogenes and Francisella novicida, which profoundly alter eukaryotic cell biology through the secretion of virulence factors known to hijack and thwart cellular stress responses in order to unravel mechanisms of ISG15 function. The consequences of ISG15 modification on substrate fate remain to be determined. Here we identified thirteen independent infection-induced ISG15-modification sites on actin binding proteins using label-free quantitative proteomics including three modified lysines on Arp3. ISGylation of actin-binding and nucleating proteins slows actin comet tail speed and alters comet tail morphology. When properly controlled, this serves as a host defense strategy to directly restrict actin-mediated pathogen spread. Ultimately, our discovery links host innate immune responses to cytoskeletal dynamics with therapeutic implications for viral infection and metastasis.
