Title Information
Title
Biochemical and Structural Features of Biotechnology
Type of Resource (primo)
dissertations
Name: Personal
Name Part
Johnson, Victoria
Role
Role Term: Text
creator
Name: Personal
Name Part
Fawzi, Nicolas
Role
Role Term: Text
Advisor
Name: Personal
Name Part
Lisi, George
Role
Role Term: Text
Reader
Name: Personal
Name Part
Naik, Mandar
Role
Role Term: Text
Reader
Name: Corporate
Name Part
Brown University. Biology and Medicine: Biotechnology
Role
Role Term: Text
sponsor
Origin Information
Copyright Date
2025
Physical Description
Extent
XI, 39 p.
digitalOrigin
born digital
Note: thesis
Thesis (Sc. M.)--Brown University, 2025
Genre (aat)
theses
Abstract
Liquid-liquid phase separation (LLPS) has been rapidly gaining acceptance as a powerful mechanism to explain the formation of membrane-less organelles and their function, playing a vital role in physiology and disease. Different types of interactions can contribute to phase separation, such as protein-protein, protein-RNA and RNA-RNA interactions. In this thesis, biochemical assays were used to determine how different structural domains and features of RNA-binding proteins contribute to phase separation properties for two different multidomain proteins. Biomolecular condensates often contain intrinsically disordered regions (IDRs) and RNA binding domains (RBDs), both of which the Xenopus heterogeneous nuclear ribonucleoprotein AB (hnRNPAB) X2 and Negative Elongation Factor E (NELFE) proteins possess. I found that full-length hnRNPAB X2 can form assemblies in vitro, while its IDR and RBD domains are able to form liquid condensates both in the presence and absence of Xenopus -globin RNA. Droplets formed from the RBD exhibit liquid behavior with wetting and fusing properties, while X2 full length and the IDR domains form amorphous assemblies that cluster together and do not fuse. Additionally, NELFE full length and a deletion variant removing the RNA recognition motif (∆RRM) result in phase separation only in the presence of polyadenylic acid (Poly A RNA). Deletion of the negatively charged low complexity sequence 1 (∆LCS1) phase separates regardless of the presence of RNA. However, removing the RD repeat low complexity sequence two (∆LCS2) completely abolishes droplet formation. A turbidity assay performed with full length NELFE showed that it contains properties of RNA mediated re-entrant phase separation. These results suggest that different proteins can possess a range of different biochemical properties as well as structural features that influence and regulate the dynamics of biomolecular condensates. These insights will provide a deeper understanding of how RNA-binding proteins and IDR containing proteins can regulate dynamics of biomolecular condensates in disease states.
Subject
Topic
liquid-liquid phase separation
Subject
Topic
Structural biology
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01086260")
Topic
RNA-protein interactions
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01079705")
Topic
Protein-protein interactions
Subject
Topic
Biomolecular condensates
Language
Language Term (ISO639-2B)
English
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20250707