Single Neuron Contributions to Sensory Behaviors in Drosophila melanogaster Open Access

Eliason, Jessica (Fall 2017)

Permanent URL: https://etd.library.emory.edu/concern/etds/8g84mm241?locale=en
Published

Abstract

Sensory systems are key to understanding how neuron circuity translates

environmental stimuli into behavioral output. Neurons transform information about our

surroundings into electrical signals. By working in coordination, neurons relay

information about our world and allow us to perceive and react appropriately to it.

However, the rules by which sensory input is interpreted by neuronal circuitry is poorly

understood.

 

My graduate work contributes to understanding sensory systems by mapping

functions to sensory neurons. Mapping includes answering the following: Which sensory

neurons contribute to a particular behavior? What features of the stimulus are extracted

by a specific neuron? How does a single neuron incorporate with others in a circuit to

produce a behavior?

 

I have used Drosophila melanogaster, the fruit fly, to better understand how

single sensory neurons function and communicate. Fly brains have only around 100,000

neurons while human brains have around 100 billion neurons. Yet, fly sensory systems

operate on the same basic principles as our own.1 Flies are sufficiently complex to

produce sophisticated behaviors but are sufficiently simple that an understanding of the

causal neuronal mechanisms is within our reach. 2 Drosophila provides a simpler, more

tractable, and more genetically malleable system to study the broadly-relevant principles

by which sensory information is encoded by neurons.

 

Somehow through the structure of receptors and activity of neurons, Drosophila

sensory systems carry out remarkably complex tasks. For example, flies use an olfactory

system to discriminate among innumerable diverse chemicals. The olfactory system

copes with the “noise” of irrelevant chemicals and distinguishes the relative quantity and

quality of odorants. Ultimately, the animal produces a behavioral response to this

information such as moving towards mates or avoiding predators. The visual system is

likewise extraordinary. From the simple act of photons hitting a receptor, the intricate

visual circuity encodes visual features such as contrast, speed, intensity, wavelength,

complexity, direction, distance, texture, polarization etc. Flies use this information for

myriad behaviors including navigation, breeding, feeding, and predator avoidance.

 

In the next three chapters, I will describe specific projects in the olfactory and

visual sensory systems that aim to illuminate neuronal mechanisms of sensation and

behavior.

Table of Contents

Contents

Thesis Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

 

Chapter 1: A GAL80 collection to nullify transgenes in Drosophila olfactory sensory

neurons. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Supplemental Figures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

Auxiliary Projects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Materials and Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

 

Chapter 2: A Screen to Identify Neuronal Candidates of Color and Translational

Motion Pathways in Drosophila. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

Supplemental Figures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75

Materials and Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78

 

Chapter 3: A Novel Neuronal Pathway to Encode Regressive Motion and Regulate

Forward Walking Speed in Drosophila. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

Supplemental Figures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113

Materials and Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .119

 

Thesis Discussion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

 

 

List of Figures

 

Chapter 1

Figure 1: Olfactory Sensory Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Figure 2: Advantages of using a GAL80 over a null mutation. . . . . . . . . . . . . . . . 8

Figure 3: Or-GAL80 reagents eliminate GAL4 activity . . . . . . . . . . . . . . . . . . . .12

Figure 4: ORN responses to CO2 in a Single Sensillum Recordings (SSR) . . . . .13

Figure 5: Use of Or-GAL80 reagents in a behavioral experiment. . . . . . . . . . . . .14

Figure S1: GAL80 reduces GAL4 expression in larvae . . . . . . . . . . . . . . . . . . . .19

Figure S2: DSCP required in destination vector

for effective GAL80 expression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Figure S3: GAL80 Specificity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20

Table S1: PCR Primers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Table S2: Sequencing Primers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Figure A1: Peripheral Neuronal Pairings in a Behavioral Assay. . . . . . . . . . . . . 25

Figure A2: Isolated OSNs and Volumetric Plasticity. . . . . . . . . . . . . . . . . . . . . . 28

Figure A3: Olfactory System with only BmOR1 OSNs. . . . . . . . . . . . . . . . . . . . 32

Figure A4: Example of a behavior using the fly described in Figure A3. . . . . . . 34

 

Chapter 2

Figure 1: Anatomy of the Visual System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44

Explanatory Insert: A Model for Motion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47

Figure 2: High-Throughput Screen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Figure 3: Behavior/Anatomy Screen Schematic. . . . . . . . . . . . . . . . . . . . . . . . . 55

Table 1: Summary of Screen Phase I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Figure 4: Results of Screen, Phase I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57

Figure 5: Sample Web Page. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Figure 6: Brain Anatomy Maps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62

Figure 7: Screen Phase II. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63

Table 2: Summary of Screen Phase II. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Figure 8: Expected Hits from screen Phase II. . . . . . . . . . . . . . . . . . . . . . . . . . . .65

Figure 9: Novel Correlates of Motion Vision. . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Figure S1: Single Fly Behavior. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Figure S2: Adding Kir2.1 to Screen Phase II. . . . . . . . . . . . . . . . . . . . . . . . . . . . 75

Figure S3: Two models for “Against” Behavior. . . . . . . . . . . . . . . . . . . . . . . . . . 76

Figure S4: Hits from screen with treadmill assay. . . . . . . . . . . . . . . . . . . . . . . . . 77

 

Chapter 3

Figure 1: Translation and Rotation Optic Flow. . . . . . . . . . . . . . . . . . . . . . . . . . .87

Figure 2: LPC1 Anatomy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .89

Figure 3: LPC1 Behavior. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Figure 4: Control responses to translational and rotational stimuli. . . . . . . . . . . 93

Figure 5: LPC1 detects Regressive Motion and Modulates Walking Speed. . . . 95

Figure 6: LPC1 Imaging and Behavior. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .98

Figure 7: LPC1 Activation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .103

Figure 8: Functional Connectivity of LPC1. . . . . . . . . . . . . . . . . . . . . . . . . . . . .107

Figure S1: LPC1 with Different Effectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .113

Figure S2: LPC1 Split Lines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

Figure S3: Speed Tuning of LPC1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .115

Figure S4: TEM Tracing of LPC1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .116

Figure S5: Contrast Tuning of Walking Flies. . . . . . . . . . . . . . . . . . . . . . . . . . . 117

Figure S6: Contrast Tuning of LPC1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .118

About this Dissertation

Rights statement
  • Permission granted by the author to include this thesis or dissertation in this repository. All rights reserved by the author. Please contact the author for information regarding the reproduction and use of this thesis or dissertation.
School
Department
Degree
Submission
Language
  • English
Research field
Keyword
Committee Chair / Thesis Advisor
Committee Members
Last modified

Primary PDF

Supplemental Files