Title Information
Title
A Distinct Role for Endosomal Na+-H+ Exchanger 9 (NHE9) from NHE6 in Neuronal Development
Name: Personal
Name Part
Sciarra, Laura N
Role
Role Term: Text
creator
Origin Information
Copyright Date
2017
Physical Description
Extent
14, 118 p.
digitalOrigin
born digital
Note
Thesis (Ph.D.)--Brown University, 2017
Name: Personal
Name Part
Morrow, Eric
Role
Role Term: Text
Director
Name: Personal
Name Part
Hart, Anne
Role
Role Term: Text
Reader
Name: Personal
Name Part
Connors, Barry
Role
Role Term: Text
Reader
Name: Personal
Name Part
Manzini, M
Role
Role Term: Text
Reader
Name: Corporate
Name Part
Brown University. Neuroscience
Role
Role Term: Text
sponsor
Genre (aat)
theses
Abstract
Autism constitutes a diverse set of disorders thought to affect neuronal connectivity and circuit development. Its etiology is heterogeneous, but certain rare genetic mutations have been implicated in autism. In this thesis, I focus on endosomal Na+-H+ exchangers, NHE6 and NHE9, and their roles in the process of neuronal development. I first describe the development of unique reagents crucial to our studies, after which I utilize those reagents to answer fundamental research questions. First, where within the endosomal pathway of neurons are Nhe6 and Nhe9 localized, and how do these localization patterns relate to one another? Second, what is the effect of Nhe9 loss on endosomal pH within neurons? And third, given the contrasting results in pH measurement with Nhe6 and Nhe9 loss, what is the effect of Nhe6 and Nhe9 on the trafficking of cargo throughout the endosomal system? More specifically, Chapter 3 demonstrates that, in contrast to previous studies of mammalian cell lines, Nhe6 and Nhe9 localize to all endosomal compartments within primary hippocampal neurons. The localization patterns of Nhe6 and Nhe9 overlap to some extent; however, in large measure, their localizations are distinct. In Chapter 4, I show that loss of Nhe9 results in an increase in more alkaline endosomes in neurons, a surprising yet intriguing result, based on prior knowledge that Nhe6 loss overacidifies the endosome. I then proceed to investigate the effect of Nhe6 and Nhe9 loss on the trafficking of cargo through endosomes, as a model to explain the unexpected pH result. Data from these studies suggest that there is a back-up of cargo in more alkaline early endosomes in Nhe9-null neurons, whereas Nhe6-null neurons may represent an acceleration of cargo to more acidic late endosomes. Thus, the work described within this thesis demonstrates a distinct role for NHE9 from NHE6 in neuronal development and informs the field as to the relationship between these two proteins.
Subject
Topic
NHE9
Subject
Topic
NHE6
Subject
Topic
Neuronal Development
Subject
Topic
Endosomes
Subject
Topic
Colocalization
Subject
Topic
Neuronal Arborization
Subject
Topic
Endosomal pH
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20170531
Identifier: DOI
10.7301/Z0ST7N8K
Access Condition: rights statement (href="http://rightsstatements.org/vocab/InC/1.0/")
In Copyright
Access Condition: restriction on access
Collection is open for research.
Type of Resource (primo)
dissertations