Abstract
Ubiquilin 2 (UBQLN2) is a protein that recognizes ubiquitinated substrates and transports them to degradation machinery such as the proteasome. This pathway is crucial for protein quality control and disruptions in it may lead to neurodegenerative diseases such as Amyotrophic Lateral Sclerosis (ALS). UBQLN2 can coalesce to form puncta within the cell. Puncta are still liquid droplets but are separate from the dilute surrounding. It has been shown in vitro that certain domains of the UBQLN2 protein are crucial for its ability to form droplets. However, the influence of these droptlets within cellular UBQLN2 is less understood. The following research investigates puncta formation modu-lation by UBQLN2 expression, domain structure, experiment time, and environmental heat stress. Information about the fluorescently tagged UBQLN2 brightness and area are used to measure the percentage of the cell covered by puncta or Percent Puncta by Area (PPA). The data demonstrate the expression dependence of UBQLN2. Under control conditions, when the cell expresses more of the protein, more puncta are formed. Certain variants of the UBQLN2 protein increase punc-ta formation expression dependence while others almost eliminate it. Output measurements also demonstrate that heat stress modulates UBQLN2 puncta formation for most of the protein variants. For some variants, heat stress increases puncta formation while other variants show less puncta dependency with heat and time. The combined results demonstrate the importance of multiple segments of UBQLN2 on its cellular function and how these components function during stress..
Recommended Citation
Brown, Mallory
(2025)
"UBQLN2 Puncta Formation Dependency on Expression, Domain Structure, and Heat Stress,"
The Crown: Syracuse Honors Research Journal: Vol. 2, Article 17.
Available at:
https://surface.syr.edu/thecrown/vol2/iss1/17