Title Information
Title
More Than Meets the Eye: Molecular Diversity of the Intrinsically Photosensitive Ganglion Cells Regulating Circadian Photoentrainment
Name: Personal
Name Part
Berg, Daniel
Role
Role Term: Text
creator
Name: Personal
Name Part
Berson, David
Role
Role Term: Text
Advisor
Name: Personal
Name Part
Wessel, Gary
Role
Role Term: Text
Reader
Name: Personal
Name Part
Barnea, Gilad
Role
Role Term: Text
Reader
Name: Personal
Name Part
Morrow, Eric
Role
Role Term: Text
Reader
Name: Personal
Name Part
Sanes, Joshua
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
xviii, 275 p.
digitalOrigin
born digital
Note: thesis
Thesis (Ph. D.)--Brown University, 2017
Genre (aat)
theses
Abstract
Chapters 1-3: Intrinsically photosensitive retinal ganglion cells (ipRGCs) are rare mammalian photoreceptors essential for non-image-forming vision functions, such as circadian photoentrainment and the pupillary light reflex. ipRGCs comprise multiple subtypes distinguishable by morphology, physiology, projections, and levels of expressed Opn4/Melanopsin, the ipRGC photopigment. Despite their neuronal specializations, the molecular identity and subtype-specific differences of ipRGCs remain elusive. Here, we present a comprehensive gene expression profiles of postnatal and adult mouse ipRGCs, suggesting dozens of genes not previously known to be highly enriched in ipRGCs. We reveal that Rasgrp1, a Ras GEF (guanine nucleotide exchange factor), and the T-box transcription factor Tbx20 are selectively expressed in a subpopulation of ipRGCs that are not restricted to a single, established type. Finally, we demonstrate that the ipRGCs regulating circadian photoentrainment are unexpectedly diverse at the molecular level. Our synthesis of previously unknown ipRGC markers provides a fuller appreciation of the complex molecular landscape across mammalian ipRGC types. Chapter 4: Genetically modified Cre strains permit cell-type-specific labeling and functional manipulations. We illustrate the utility of Rbp4-Cre mice for studying selected retinal cell types that encode the intensity of light and the direction of motion. Intensity encoding is thought to be uniquely mediated by intrinsically photosensitive retinal ganglion cells (ipRGCs). ipRGCs transmit intensity signals not only to the brain, but also intraretinally, partly through gap junctions to polyaxonal amacrine cells. We show that these amacrine cells are tagged in Rbp4-Cre mice, confirm their persistent light responses under chemical synaptic blockade, and show that they co-stratify with, and are tracer-coupled to M2 ipRGCs. The line also labels a variant of direction-selective RGCs, and a RGC that lacks intrinsic photosensitivity but encodes intensity.
Subject
Topic
iprgcs
Subject
Topic
opn4
Subject
Topic
melanopsin
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01096222")
Topic
Retinal ganglion cells
Subject
Topic
rasgrp1
Subject
Topic
tbx20
Subject
Topic
rbp4
Subject
Topic
transgenic reporter
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/00861558")
Topic
Circadian rhythms
Subject (fast) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01168044")
Topic
Visual pathways
Subject
Topic
cell types
Subject
Topic
terminal differentiation
Subject
Topic
photoentrainment
Subject
Topic
molecular diversity
Subject
Topic
non-image forming
Subject
Topic
phototransduction
Subject
Topic
intrinsically photosensitive
Language
Language Term (ISO639-2B)
English
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20180615
Identifier: DOI
10.26300/zh8v-qx46
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