Date of Award
Spring 5-6-2024
Degree Type
Thesis
Degree Name
Master of Science in Integrative Biology
Department
Department of Molecular and Cellular Biology
Committee Chair/First Advisor
Anton Bryantsev
Second Advisor
Brandon Carpenter
Third Advisor
Thomas Leeper, Carol Chrestensen
Abstract
Understanding mechanisms of intracellular sorting is a fundamental inquiry of cell biology. We used the B-body and protein Bruno (Bru) as a model to study the formation of nuclear domains that are membraneless organelles inside the cell nucleus. Specifically, we sought to identify protein sequences that regulate Bru's affinity to B-bodies and protein aggregation. We generated various Bru mutants and subsequently tested them in vivo using fluorescence microscopy. We found that the protein solubility of Bru is determined through an interplay of RNA recognition motifs (RRMs) and intrinsically disordered regions (IDRs). Using truncation analysis, we identified a 31-amino acid region within IDR1 that may regulate Bru solubility via phosphorylation of three key amino acids. Complementarily, in a reverse genetic screen, we identified Doa kinase as a factor modulating Bru's affinity toward B-bodies. In summary, Bru accumulation at B-bodies requires all RRMs that determine the specificity, while phosphorylation of IDR1 may be needed for the protein’s release from B-bodies. Our study provides a detailed mechanistic insight into the formation of nuclear domains by RNA-binding proteins.
Included in
Cell Anatomy Commons, Cell Biology Commons, Developmental Biology Commons, Integrative Biology Commons, Molecular Genetics Commons
Comments
NSF grant 2042814