University of Kentucky UKnowledge University of Kentucky Doctoral Dissertations Graduate School 2006 CLONING AND EXPRESSION OF KEY ENDOCRINE GENES IN A STUDY ON ESTROGEN STIMULATED SEXUAL SIZE DIMORPHISM (SSD) IN YELLOW PERCH Scott George Lynn University of Kentucky, [email protected] Right click to open a feedback form in a new tab to let us know how this document benefits ou.y Recommended Citation Lynn, Scott George, "CLONING AND EXPRESSION OF KEY ENDOCRINE GENES IN A STUDY ON ESTROGEN STIMULATED SEXUAL SIZE DIMORPHISM (SSD) IN YELLOW PERCH" (2006). University of Kentucky Doctoral Dissertations. 273. https://uknowledge.uky.edu/gradschool_diss/273 This Dissertation is brought to you for free and open access by the Graduate School at UKnowledge. It has been accepted for inclusion in University of Kentucky Doctoral Dissertations by an authorized administrator of UKnowledge. For more information, please contact [email protected]. ABSTRACT OF DISSERTATION Scott George Lynn The Graduate School University of Kentucky 2006 CLONING AND EXPRESSIONOF KEY ENDOCRINE GENES IN A STUDY ONESTROGENSTIMULATED SEXUAL SIZE DIMORPHISM (SSD) INYELLOW PERCH ______________________________________ ABSTRACT OF DISSERTATION ______________________________________ A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Arts and Sciences at the University of Kentucky By Scott George Lynn Lexington, Kentucky Director: Dr. David French Westneat, Professor of Biology Lexington, Kentucky 2006 Copyright © Scott George Lynn 2006 ABSTRACT OF DISSERTATION CLONING AND EXPRESSIONOF KEY ENDOCRINE GENES IN A STUDY ONESTROGENSTIMULATED SEXUAL SIZE DIMORPHISM (SSD) INYELLOW PERCH Yellow perch ( Perca flavescens ) exhibit an estrogen stimulated sexual size dimorphism (SSD) wherein females grow faster and larger than males. In an effort to gain better understanding of this phenomenon, several genes associated with sexual development, reproduction and growth were cloned, including prolactin (PRL), somatolactin (SL), insulin-like growth factor-I (IGF-Ib), the estrogen receptors (ERα and ERβa) and ovarian aromatase (CYP19A1). Real-time quantitative PCR (qPCR) assays for all the genes listed above, plus growth hormone (GH), were developed to measure mRNA levels in pituitary, liver and ovary. Adult fish were collected from Lake Erie in the spring (May) and autumn (October) over two years and tissue mRNA levels, body weight, age, gonadasomatic index (GSI) and hepatasomatic index (HSI) were determined. Sex-specific differences included females having higher body weights, HSI and liver ERα mRNA levels than males and males having higher liver ERβa and liver CYP19A1 mRNA levels than females. Season had a significant effect on growth factors (GH and IGF-Ib), with higher mRNA levels in spring, which corresponded with higher liver CYP19A1 mRNA levels. Ovary CYP19A1 mRNA levels, which were higher in autumn, had a significant negative correlation with GH and IGF-Ib mRNA levels and liver ERβa mRNA levels had a significant positive correlation with IGF-Ib mRNA levels. A brood of juvenile yellow perch was sampled through the first year of development up to 421 days post-hatching (dph). There was a significant effect of dph on body weight, GH, PRL, SL, IGF-Ib, liver ERα, liver ERβa and ovary CYP19A1 mRNA levels. Only liver ERβa mRNA had a significant effect of sex and exhibited significant differences between males and females at 379 and 421 days post-hatching (dph). This work on yellow perch can provide predictive capabilities for estrogen- dependent physiological processes in other species, especially teleosts, and can also make yellow perch an exciting option for future ecotoxicogenomic studies. Key words: estrogen, growth, gene expression, yellow perch, sex Scott George Lynn October 13 th , 2006 CLONING AND EXPRESSIONOF KEY ENDOCRINE GENES IN A STUDY ONESTROGENSTIMULATED SEXUAL SIZE DIMORPHISM (SSD) INYELLOW PERCH By Scott George Lynn Dr. David F. Westneat Director of Dissertation Dr. Brian Rymond Director of Graduate Studies October 13 th , 2006 RULES FOR THE USE OF DISSERTATIONS Unpublished dissertations submitted for the Doctor’s degree and deposited in the University of Kentucky Library are as a rule open for inspection, but are to be used only with due regard to the rights of the authors. Bibliographical references may be noted, but quotations or summaries of parts may be published only with the permission of the author, and with the usual scholarly acknowledgments. Extensive copying or publication of the dissertation in whole or in part also requires the consent of the Dean of Graduate Studies of the University of Kentucky A library that borrows this dissertation for use by its patrons is expected to secure the signature of each user. Name Date DISSERTATION Scott George Lynn The Graduate School University of Kentucky 2006 CLONING AND EXPRESSIONOF KEY ENDOCRINE GENES IN A STUDY ONESTROGENSTIMULATED SEXUAL SIZE DIMORPHISM (SSD) INYELLOW PERCH ______________________________________ DISSERTATION ______________________________________ A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the College of Arts and Sciences at the University of Kentucky By Scott George Lynn Lexington, Kentucky Director: Dr. David French Westneat, Professor of Biology Lexington, Kentucky 2006 Copyright © Scott George Lynn 2006 DEDICATION I dedicate this dissertation to Emily Blair Morrison: my fiancée, my love, my inspiration and my life. ii ACKNOWLEDGEMENTS “Dont look back A new day is breakin It’s been too long since I felt this way I dont mind where I get taken The road is callin Today is the day I can see It took so long to realize I’m much too strong Not to comprimise Now I see what I am is holding me down I’ll turn it around I finally see the dawn arrivin I see beyond the road I’m drivin Far away and left behind It’s a new horizon and I’m awakin now Oh I see myself in a brand new way The sun is shinin The clouds are breakin cause I can’t lose now, theres no game to play I can tell There’s no more time left to criticize I’ve seen what I could not recognize Everthing in my life was leading me on But I can be strong I finally see the dawn arrivin I see beyond the road I’m drivin Far away and left behind.” -“Don’t Look Back” by Boston on the album “Don’t Look Back” released 1978 iii TABLE OF CONTENTS Acknowledgements ............................................................................................................iii List of Tables...................................................................................................................... vi List of Figures ...................................................................................................................vii List of Files.........................................................................................................................ix Chapter 1: Introduction ....................................................................................................... 1 1.1 Yellow Perch..................................................................................................... 1 1.2 Pituitary Genes .................................................................................................. 2 1.3 Estrogen Related Genes .................................................................................... 4 1.4 Conclusions....................................................................................................... 5 1.5 Figures............................................................................................................... 6 Chapter 2: Sequence and sex-specific tissue expression of prolactin, somatolactin and insulin-like growth factor-I cDNAs in yellow perch .............................................. 7 2.1 Introduction ....................................................................................................... 7 2.2 Methods........................................................................................................... 13 2.3 Results............................................................................................................. 16 2.4 Discussion ....................................................................................................... 21 2.5 Tables and Figures .......................................................................................... 27 Chapter 3: Sequence and sex-specific tissue expression of estrogen receptor α, estrogen receptor βa and ovarian aromatase (CYP19A1) cDNAs in yellow perch............. 56 3.1 Introduction ..................................................................................................... 56 3.2 Methods........................................................................................................... 60 3.3 Results............................................................................................................. 63 3.4 Discussion ....................................................................................................... 69 3.5 Tables and Figures .......................................................................................... 80 Chapter 4: Sex-specific and seasonal mRNA levels of key endocrine genes in adult yellow perch from Lake Erie............................................................................... 143 4.1 Introduction ..................................................................................................