Title Information
Title
Cytoskeletal morphogenesis in Trypanosoma brucei
Name: Personal
Name Part
Sinclair Roth, Amy
Role
Role Term: Text
creator
Name: Personal
Name Part
Johnson, Mark
Role
Role Term: Text
Reader
Name: Personal
Name Part
Bennett, Richard
Role
Role Term: Text
Reader
Name: Personal
Name Part
Fawzi, Nicolas
Role
Role Term: Text
Reader
Name: Personal
Name Part
Rice, Luke
Role
Role Term: Text
Reader
Name: Corporate
Name Part
Brown University. Department of Molecular Biology, Cell Biology and Biochemistry
Role
Role Term: Text
sponsor
Origin Information
Copyright Date
2021
Physical Description
Extent
xiii, 216 p.
digitalOrigin
born digital
Note: thesis
Thesis (Ph. D.)--Brown University, 2021
Genre (aat)
theses
Abstract
Cell division is fundamental to life. As more divergent organisms become tractable to genetic manipulation, we have discovered that the molecular mechanisms that govern cell division are as variable as the organisms themselves. The unicellular protist parasite Trypanosoma brucei, the causative agent of African sleeping sickness, is separated from humans by 1 billion years of evolution. It has a highly asymmetric cell shape with a broad posterior and narrow anterior that is created by an extensive cytoskeletal structure known as the subpellicular array. The subpellicular array consists of a single layer of crosslinked microtubules that underlie the plasma membrane and persist throughout the cell cycle. To divide, T. brucei has developed a unique mode of cytokinesis that maintains cell shape and ensures array integrity. It does not employ an actomyosin contractile ring as in yeast and metazoan systems; rather, cytokinesis takes place asymmetrically along the long axis of the cell. Cleavage furrow ingression initiates at the narrow cell anterior and follows the helical path of array microtubules towards the cell posterior. However, the molecular mechanisms that govern this unique mode of cytokinesis while maintaining array shape are not known. In this dissertation, we explore the link between cytokinesis and cell shape in T. brucei. In Chapter 2, we determine that the first cytokinetic protein discovered in T. brucei, TOEFAZ1, functions as a scaffold to recruit cytokinetic regulators to the initiation point of cleavage furrow ingression. This work precipitated multiple protein-proximity interaction assays to identify TOEFAZ1 binding partners that are involved subpellicular array remodeling during cytokinesis, which led to the discovery of PAVE1. In Chapter 3, we find that PAVE1 is a component of the inter-microtubule crosslinks of the subpellicular array and is necessary to maintain the length and shape of the array at the cell posterior. We also discover that the array is organized into subdomains characterized by the differential localization of array-associated proteins that locally tune array shape. The work presented in this thesis establishes the foundation for understanding the molecular mechanism of cytokinesis in T. brucei, which is inseparable from the cellular architecture created by the subpellicular array.
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00886282")
Topic
Cytology
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01024734")
Topic
Molecular biology
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00831961")
Topic
Biochemistry
Language
Language Term (ISO639-2B)
English
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20210607
Type of Resource (primo)
dissertations