New models of brain and behavioral sex change in the common clownfish, Amphiprion ocellaris

Parker, Coltan Gable

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https://hdl.handle.net/2142/116042 Copy

Description

Title

New models of brain and behavioral sex change in the common clownfish, Amphiprion ocellaris

Author(s)

Parker, Coltan Gable

Issue Date

2022-07-07

Director of Research (if dissertation) or Advisor (if thesis)

Rhodes, Justin S

Doctoral Committee Chair(s)

Rhodes, Justin S

Committee Member(s)

• Bell, Alison M
• Hauber, Mark E
• Juraska, Janice M

Department of Study

Neuroscience Program

Discipline

Neuroscience

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

• sexual differentiation
• sex change
• anemonefish
• preoptic area
• neurogenesis
• parenting
• aggression
• single cell RNA-sequencing

Abstract

Sex differences in the preoptic area of the hypothalamus (POA) are essential for neuroendocrine regulation of gonadal physiology and sexual reproduction. The POA is a deeply conserved brain structure across vertebrate species, making it an ideal focal point for the comparative study of sexual differentiation in the brain in non-model species. Sex-changing fishes provide a particularly unique opportunity to uncover the mechanisms underlying sexual differentiation of the brain and regulation of sexual phenotypes. Sex change requires the complete transformation of functional gonads and sexually-differentiated behaviors in the adult organism, which in turn require transformation of sexually-differentiated control mechanisms in the brain. However, very little is known about how the brain changes in any sex-changing fish, particularly those that change sex from male-to-female. The goal of this thesis was to determine key features of male-to-female POA sex change in the model anemonefish Amphriprion ocellaris. Chapter 1 reviews what is known about the process of sex change in anemonefish at the level of brain, behavior, and gonads, as well as how sex change fits into their unique life history. Chapter 2 reports research that rewrites our understanding of behavioral sex change in anemonefish, and casts results from previous studies in a new light. Chapter 3 reports research that investigates the role for new cell genesis in brain sex change for the first time in any sex-changing fish. Chapter 4 reports research that maps the molecular and cellular diversity of the anemonefish forebrain, revealing remarkably widespread sex differences in abundance and transcriptome of numerous cell-types. This work rethinks our understanding of sex change in anemonefish, and in doing so develops this emerging model into a holistic, unique, and promising model for the study of sexual differentiation.

Graduation Semester

2022-08

Type of Resource

Thesis

Copyright and License Information

Copyright 2022 Coltan Parker

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