Title Information
Title
GA-Binding Proteins Regulate Dosage Compensation in Drosophila Melanogaster
Name: Personal
Name Part
Kaye, Emily G.
Role
Role Term: Text
creator
Name: Personal
Name Part
Freiman, Richard
Role
Role Term: Text
Reader
Name: Personal
Name Part
Wharton, Kristi
Role
Role Term: Text
Reader
Name: Personal
Name Part
Larschan, Erica
Role
Role Term: Text
Advisor
Name: Personal
Name Part
Guertin, Michael
Role
Role Term: Text
Reader
Name: Personal
Name Part
Fawzi, Nicolas
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
2017
Physical Description
Extent
xvii, 241 p.
digitalOrigin
born digital
Note: thesis
Thesis (Ph. D.)--Brown University, 2017
Genre (aat)
theses
Abstract
Abstract of “GA-Binding Proteins Regulate Dosage Compensation in Drosophila melanogaster” by Emily Grace Kaye, Ph.D., Brown University, May 2018 A transcription factor (TF) will bind only a subset of its potential binding sites in the genome. Which sites are bound ultimately determines the functional impact of a TF on the cell. To improve our understanding of TF targeting and transcriptional regulation, we compare the role of two essential proteins with similar consensus binding motifs: GAGA Factor (GAF), and Chromatin-Linked Adapter for MSL Proteins (CLAMP). Both target GA-rich sequences genome-wide, yet CLAMP has a specialized role in recruiting the Male-Specific Lethal (MSL) complex to the single male X-chromosome in Drosophila melanogaster for the process known as gene dosage compensation. Dosage compensation corrects the imbalance between gene expression of sex-linked genes and autosomal genes. MSL facilitates the increase in transcription of genes on the male X-chromosome by first localizing to GA-rich DNA sequence motifs clustered in Chromatin Entry Sites (CES) on the X-chromosome. CLAMP is required for MSL recruitment to CES, while GAF depletion can cause male-specific lethality but leads to loss of MSL at only a single site when measured by immunostaining. Since both TFs are essential in males and females, we first investigated differences in GA-binding site sequences, including analysis of the distribution of sequences on X versus autosomes. Next, to test their individual versus overlapping functions, we used in vitro gel-shift assays to determine that CLAMP outcompetes GAF for long GA-repeat stretches, thus contributing to the differences observed between binding patterns for the two proteins. To investigate potential interactions at shared binding sites, we performed RNA interference (RNAi) experiments followed by chromatin immunoprecipitation (ChIP) to test for relocalization of each factor after the other has been knocked-down. Finally, we identify a shared function between GAF and CLAMP as part of an insulator complex, which may explain the requirement for both proteins in MSL targeting and as well as reveals a shared non sex-specific essential function. Overall our experiments provide insight into TF targeting for dosage compensation, an example of context-specific gene regulation.
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01154564")
Topic
Transcription factors
Subject
Topic
dosage compensation
Language
Language Term (ISO639-2B)
English
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20180615
Identifier: DOI
10.26300/ek07-en15
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