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Smaga CR, Bock SL, Johnson JM, Rainwater T, Singh R, Deem V, Letter A, Brunell A, Parrott BB. The influence of incubation temperature on offspring traits varies across northern and southern populations of the American alligator ( Alligator mississippiensis). Ecol Evol 2024; 14:e10915. [PMID: 38371857 PMCID: PMC10869887 DOI: 10.1002/ece3.10915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 01/10/2024] [Accepted: 01/15/2024] [Indexed: 02/20/2024] Open
Abstract
Maternal provisioning and the developmental environment are fundamental determinants of offspring traits, particularly in oviparous species. However, the extent to which embryonic responses to these factors differ across populations to drive phenotypic variation is not well understood. Here, we examine the contributions of maternal provisioning and incubation temperature to hatchling morphological and metabolic traits across four populations of the American alligator (Alligator mississippiensis), encompassing a large portion of the species' latitudinal range. Our results show that whereas the influence of egg mass is generally consistent across populations, responses to incubation temperature show population-level variation in several traits, including mass, head length, head width, and residual yolk mass. Additionally, the influence of incubation temperature on developmental rate is greater at northern populations, while the allocation of maternal resources toward fat body mass is greater at southern populations. Overall, our results suggest that responses to incubation temperature, relative to maternal provisioning, are a larger source of interpopulation phenotypic variation and may contribute to the local adaptation of populations.
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Affiliation(s)
- Christopher R. Smaga
- Eugene P. Odum School of EcologyUniversity of GeorgiaAthensGeorgiaUSA
- The University of Georgia's Savannah River Ecology LaboratoryAikenSouth CarolinaUSA
| | - Samantha L. Bock
- Eugene P. Odum School of EcologyUniversity of GeorgiaAthensGeorgiaUSA
- The University of Georgia's Savannah River Ecology LaboratoryAikenSouth CarolinaUSA
| | - Josiah M. Johnson
- Eugene P. Odum School of EcologyUniversity of GeorgiaAthensGeorgiaUSA
- The University of Georgia's Savannah River Ecology LaboratoryAikenSouth CarolinaUSA
| | - Thomas Rainwater
- Belle W. Baruch Institute of Coastal Ecology and Forest ScienceClemson UniversityGeorgetownSouth CarolinaUSA
- Tom Yawkey Wildlife CenterGeorgetownSouth CarolinaUSA
| | - Randeep Singh
- Belle W. Baruch Institute of Coastal Ecology and Forest ScienceClemson UniversityGeorgetownSouth CarolinaUSA
| | - Vincent Deem
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation CommissionGainesvilleFloridaUSA
| | - Andrew Letter
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation CommissionGainesvilleFloridaUSA
| | - Arnold Brunell
- Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation CommissionGainesvilleFloridaUSA
| | - Benjamin B. Parrott
- Eugene P. Odum School of EcologyUniversity of GeorgiaAthensGeorgiaUSA
- The University of Georgia's Savannah River Ecology LaboratoryAikenSouth CarolinaUSA
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2
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Toyota K, Akashi H, Ishikawa M, Yamaguchi K, Shigenobu S, Sato T, Lange A, Tyler CR, Iguchi T, Miyagawa S. Comparative analysis of gonadal transcriptomes between turtle and alligator identifies common molecular cues activated during the temperature-sensitive period for sex determination. Gene 2023; 888:147763. [PMID: 37666375 DOI: 10.1016/j.gene.2023.147763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 08/09/2023] [Accepted: 09/01/2023] [Indexed: 09/06/2023]
Abstract
The mode of sex determination in vertebrates can be categorized as genotypic or environmental. In the case of genotypic sex determination (GSD), the sexual fate of an organism is determined by the chromosome composition with some having dominant genes, named sex-determining genes, that drive the sex phenotypes. By contrast, many reptiles exhibit environmental sex determination (ESD), whereby environmental stimuli drive sex determination, and most notably temperature. To date, temperature-dependent sex determination (TSD) has been found in most turtles, some lizards, and all crocodylians, but commonalities in the controlling processes are not well established. Recent innovative sequencing technology has enabled investigations into gonadal transcriptomic profiles during temperature-sensitive periods (TSP) in various TSD species which can help elucidate the controlling mechanisms. In this study, we conducted a time-course analysis of the gonadal transcriptome during the male-producing temperature (26℃) of the Reeve's turtle (Chinese three-keeled pond turtle) Mauremys reevesii. We then compared the transcriptome profiles for this turtle species during the TSP with that for the American alligator Alligator mississippiensis to identify conserved reptilian TSD-related genes. Our transcriptome-based findings provide an opportunity to retrieve the candidate molecular cues that are activated during TSP and compare these target responses between TSD and GSD turtle species, and between TSD species.
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Affiliation(s)
- Kenji Toyota
- Department of Biological Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan; Noto Marine Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Ogi, Noto-cho, Ishikawa 927-0553, Japan; Department of Biological Sciences, Faculty of Science, Kanagawa University, 2946 Tsuchiya, Hiratsuka, Kanagawa 259-1293, Japan.
| | - Hiroshi Akashi
- Department of Biological Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan; Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-0882, Japan
| | - Momoka Ishikawa
- Department of Biological Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan
| | - Katsushi Yamaguchi
- Trans-Omics Facility, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji-cho, Okazaki, Aichi 444-8585, Japan
| | - Shuji Shigenobu
- Trans-Omics Facility, National Institute for Basic Biology, 38 Nishigonaka, Myodaiji-cho, Okazaki, Aichi 444-8585, Japan
| | - Tomomi Sato
- Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, Kanagawa 236-0027, Japan
| | - Anke Lange
- Biosciences, Faculty of Health and Life Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Charles R Tyler
- Biosciences, Faculty of Health and Life Sciences, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Taisen Iguchi
- Noto Marine Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Ogi, Noto-cho, Ishikawa 927-0553, Japan; Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, Kanagawa 236-0027, Japan
| | - Shinichi Miyagawa
- Department of Biological Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan.
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3
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Himelreich Perić M, Takahashi M, Ježek D, Cunha GR. Early development of the human embryonic testis. Differentiation 2023; 129:4-16. [PMID: 35961887 DOI: 10.1016/j.diff.2022.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/11/2022] [Accepted: 07/12/2022] [Indexed: 01/25/2023]
Abstract
Human gonadal development culminating in testicular differentiation is described through analysis of histologic sections derived from 33-day to 20-week human embryos/fetuses, focusing on early development (4-8 weeks of gestation). Our study updates the comprehensive studies of Felix (1912), van Wagenen and Simpson (1965), and Juric-Lekic et al. (2013), which were published in books and thus are unsearchable via PubMed. Human gonads develop from the germinal ridge, a thickening of coelomic epithelium on the medial side of the urogenital ridge. The bilateral urogenital ridges contain elements of the mesonephric kidney, namely the mesonephric duct, mesonephric tubules, and mesonephric glomeruli. The germinal ridge, into which primordial germ cells migrate, is initially recognized as a thickening of coelomic epithelium on the urogenital ridge late in the 4th week of gestation. Subsequently, in the 5th week of gestation, a dense mesenchyme develops sub-adjacent to the epithelium of the germinal ridge, and together these elements bulge into the coelomic cavity forming bilateral longitudinal ridges attached to the urogenital ridges. During development, primordial cells migrate into the germinal ridge and subsequently into testicular cords that form within the featureless dense mesenchyme of the germinal ridge at 6-8 weeks of gestation. The initial low density of testicular cords seen at 8 weeks remodels into a dense array of testicular cords surrounded by α-actin-positive myoid cells during the second trimester. Human testicular development shares many features with that of mice being derived from 4 elements: coelomic epithelium, sub-adjacent mesenchyme, primordial germ cells, and the mesonephros.
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Affiliation(s)
- Marta Himelreich Perić
- Scientific Centre of Excellence for Reproductive and Regenerative Medicine, School of Medicine, University of Zagreb, 10000, Zagreb, Croatia.
| | - Marta Takahashi
- Department of Communication Sciences, Catholic University of Croatia, 10000, Zagreb, Croatia
| | - Davor Ježek
- Scientific Centre of Excellence for Reproductive and Regenerative Medicine, School of Medicine, University of Zagreb, 10000, Zagreb, Croatia; Department of Histology and Embryology, School of Medicine, University of Zagreb, 10000, Zagreb, Croatia
| | - Gerald R Cunha
- Department of Urology, University of California, 400 Parnassus Avenue, San Francisco, CA, 94143, USA
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4
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Models and Molecular Markers of Spermatogonial Stem Cells in Vertebrates: To Find Models in Nonmammals. Stem Cells Int 2022; 2022:4755514. [PMID: 35685306 PMCID: PMC9174007 DOI: 10.1155/2022/4755514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 03/21/2022] [Accepted: 04/17/2022] [Indexed: 11/24/2022] Open
Abstract
Spermatogonial stem cells (SSCs) are the germline stem cells that are essential for the maintenance of spermatogenesis in the testis. However, it has not been sufficiently understood in amphibians, reptiles, and fish because numerous studies have been focused mainly on mammals. The aim of this review is to discuss scientific ways to elucidate SSC models of nonmammals in the context of the evolution of testicular organization since rodent SSC models. To further understand the SSC models in nonmammals, we point out common markers of an SSC pool (undifferentiated spermatogonia) in various types of testes where the kinetics of the SSC pool appears. This review includes the knowledge of (1) common molecular markers of vertebrate type A spermatogonia including putative SSC markers, (2) localization of the markers on the spermatogonia that have been reported in previous studies, (3) highlighting the most common markers in vertebrates, and (4) suggesting ways of finding SSC models in nonmammals.
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5
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Whiteley SL, Wagner S, Holleley CE, Deveson IW, Marshall Graves JA, Georges A. Truncated jarid2 and kdm6b transcripts are associated with temperature-induced sex reversal during development in a dragon lizard. SCIENCE ADVANCES 2022; 8:eabk0275. [PMID: 35442724 PMCID: PMC9020659 DOI: 10.1126/sciadv.abk0275] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 03/04/2022] [Indexed: 05/23/2023]
Abstract
Sex determination and differentiation in reptiles are complex. In the model species, Pogona vitticeps, high incubation temperature can cause male to female sex reversal. To elucidate the epigenetic mechanisms of thermolabile sex, we used an unbiased genome-wide assessment of intron retention during sex reversal. The previously implicated chromatin modifiers (jarid2 and kdm6b) were two of three genes to display sex reversal-specific intron retention. In these species, embryonic intron retention resulting in C-terminally truncated jarid2 and kdm6b isoforms consistently occurs at low temperatures. High-temperature sex reversal is uniquely characterized by a high prevalence of N-terminally truncated isoforms of jarid2 and kdm6b, which are not present at low temperatures, or in two other reptiles with temperature-dependent sex determination. This work verifies that chromatin-modifying genes are involved in highly conserved temperature responses and can also be transcribed into isoforms with new sex-determining roles.
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Affiliation(s)
- Sarah L. Whiteley
- Institute for Applied Ecology, University of Canberra, Bruce, Australia
- Australian National Wildlife Collection, CSIRO National Research Collections Australia, Canberra, Australia
| | - Susan Wagner
- Institute for Applied Ecology, University of Canberra, Bruce, Australia
| | - Clare E. Holleley
- Australian National Wildlife Collection, CSIRO National Research Collections Australia, Canberra, Australia
| | - Ira W. Deveson
- Garvan Institute of Medical Research, Sydney, Australia
- St. Vincent’s Clinical School, UNSW, Sydney, Australia
| | | | - Arthur Georges
- Institute for Applied Ecology, University of Canberra, Bruce, Australia
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6
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Bock SL, Hale MD, Rainwater TR, Wilkinson PM, Parrott BB. Incubation Temperature and Maternal Resource Provisioning, but Not Contaminant Exposure, Shape Hatchling Phenotypes in a Species with Temperature-Dependent Sex Determination. THE BIOLOGICAL BULLETIN 2021; 241:43-54. [PMID: 34436964 DOI: 10.1086/714572] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
AbstractThe environment experienced during embryonic development is a rich source of phenotypic variation, as environmental signals have the potential to both inform adaptive plastic responses and disrupt normal developmental programs. Environment-by-embryo interactions are particularly consequential for species with temperature-dependent sex determination, a mode of sex determination common in non-avian reptiles and fish, in which thermal cues during a discrete period of development drive the formation of either an ovary or a testis. Here we examine the impact of thermal variation during incubation in combination with developmental exposure to a common endocrine-disrupting contaminant on fitness-related hatchling traits in the American alligator (Alligator mississippiensis), a species with temperature-dependent sex determination. Using a factorial design, we exposed field-collected eggs to five thermal profiles (three constant temperatures, two fluctuating temperatures) and two environmentally relevant doses of the pesticide metabolite dichlorodiphenyldichloroethylene; and we quantified incubation duration, sex ratios, hatchling morphometric traits, and growth (9-10 days post-hatch). Whereas dichlorodiphenyldichloroethylene exposure did not generally affect hatchling traits, constant and fluctuating temperatures produced diverse phenotypic effects. Thermal fluctuations led to subtle changes in incubation duration and produced shorter hatchlings with smaller heads when compared to the constant temperature control. Warmer, male-promoting incubation temperatures resulted in larger hatchlings with more residual yolk reserves when compared to cooler, female-promoting temperatures. Together, these findings advance our understanding of how complex environmental factors interact with developing organisms to generate phenotypic variation and raise questions regarding the mechanisms connecting variable thermal conditions to responses in hatchling traits and their evolutionary implications for temperature-dependent sex determination.
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7
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Sakae Y, Tanaka M. Metabolism and Sex Differentiation in Animals from a Starvation Perspective. Sex Dev 2021; 15:168-178. [PMID: 34284403 DOI: 10.1159/000515281] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 02/12/2021] [Indexed: 11/19/2022] Open
Abstract
Animals determine their sex genetically (GSD: genetic sex determination) and/or environmentally (ESD: environmental sex determination). Medaka (Oryzias latipes) employ a XX/XY GSD system, however, they display female-to-male sex reversal in response to various environmental changes such as temperature, hypoxia, and green light. Interestingly, we found that 5 days of starvation during sex differentiation caused female-to-male sex reversal. In this situation, the metabolism of pantothenate and fatty acid synthesis plays an important role in sex reversal. Metabolism is associated with other biological factors such as germ cells, HPG axis, lipids, and epigenetics, and supplys substances and acts as signal transducers. In this review, we discuss the importance of metabolism during sex differentiation and how metabolism contributes to sex differentiation.
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Affiliation(s)
- Yuta Sakae
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Minoru Tanaka
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
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8
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Nagahama Y, Chakraborty T, Paul-Prasanth B, Ohta K, Nakamura M. Sex determination, gonadal sex differentiation, and plasticity in vertebrate species. Physiol Rev 2020; 101:1237-1308. [PMID: 33180655 DOI: 10.1152/physrev.00044.2019] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
A diverse array of sex determination (SD) mechanisms, encompassing environmental to genetic, have been found to exist among vertebrates, covering a spectrum from fixed SD mechanisms (mammals) to functional sex change in fishes (sequential hermaphroditic fishes). A major landmark in vertebrate SD was the discovery of the SRY gene in 1990. Since that time, many attempts to clone an SRY ortholog from nonmammalian vertebrates remained unsuccessful, until 2002, when DMY/dmrt1by was discovered as the SD gene of a small fish, medaka. Surprisingly, however, DMY/dmrt1by was found in only 2 species among more than 20 species of medaka, suggesting a large diversity of SD genes among vertebrates. Considerable progress has been made over the last 3 decades, such that it is now possible to formulate reasonable paradigms of how SD and gonadal sex differentiation may work in some model vertebrate species. This review outlines our current understanding of vertebrate SD and gonadal sex differentiation, with a focus on the molecular and cellular mechanisms involved. An impressive number of genes and factors have been discovered that play important roles in testicular and ovarian differentiation. An antagonism between the male and female pathway genes exists in gonads during both sex differentiation and, surprisingly, even as adults, suggesting that, in addition to sex-changing fishes, gonochoristic vertebrates including mice maintain some degree of gonadal sexual plasticity into adulthood. Importantly, a review of various SD mechanisms among vertebrates suggests that this is the ideal biological event that can make us understand the evolutionary conundrums underlying speciation and species diversity.
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Affiliation(s)
- Yoshitaka Nagahama
- Laboratory of Reproductive Biology, National Institute for Basic Biology, Okazaki, Japan.,South Ehime Fisheries Research Center, Ehime University, Ainan, Japan.,Faculty of Biological Science and Technology, Kanazawa University, Ishikawa, Japan
| | - Tapas Chakraborty
- Laboratory of Reproductive Biology, National Institute for Basic Biology, Okazaki, Japan.,South Ehime Fisheries Research Center, Ehime University, Ainan, Japan.,Laboratory of Marine Biology, Faculty of Agriculture, Kyushu University, Fukouka, Japan.,Karatsu Satellite of Aqua-Bioresource Innovation Center, Kyushu University, Karatsu, Japan
| | - Bindhu Paul-Prasanth
- Laboratory of Reproductive Biology, National Institute for Basic Biology, Okazaki, Japan.,Centre for Nanosciences and Molecular Medicine, Amrita Vishwa Vidapeetham, Kochi, Kerala, India
| | - Kohei Ohta
- Laboratory of Marine Biology, Faculty of Agriculture, Kyushu University, Fukouka, Japan
| | - Masaru Nakamura
- Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan.,Research Center, Okinawa Churashima Foundation, Okinawa, Japan
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9
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Hale MD, Parrott BB. Assessing the Ability of Developmentally Precocious Estrogen Signaling to Recapitulate Ovarian Transcriptomes and Follicle Dynamics in Alligators from a Contaminated Lake. ENVIRONMENTAL HEALTH PERSPECTIVES 2020; 128:117003. [PMID: 33186072 PMCID: PMC7665278 DOI: 10.1289/ehp6627] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 10/09/2020] [Accepted: 10/16/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Concern has grown in recent decades over anthropogenic contaminants that interfere with the functioning of endocrine hormones. However, mechanisms connecting developmental processes to pathologies associated with endocrine-disrupting chemical (EDC) exposure are poorly understood in naturally exposed populations. OBJECTIVES We sought to a) characterize divergence in ovarian transcriptomic and follicular profiles between alligators originating from a historically EDC-contaminated site, Lake Apopka, and a reference site; b) test the ability of developmentally precocious estrogen exposure to recapitulate site-associated patterns of divergence; and c) test whether treatment with exogenous follicle-stimulating hormone (FSH) is capable of rescuing phenotypes associated with contaminant exposure and/or embryonic estrogen treatment. METHODS Alligators eggs were collected from a contaminated site and a reference site, and a subset of eggs from the reference site were treated with estradiol (E2) during embryonic development prior to gonadal differentiation. After hatching, alligators were raised under controlled laboratory settings for 5 months. Juveniles from both sites were divided and treated with exogenous FSH. Histological analyses and RNA-sequencing were conducted to characterize divergence in ovarian follicle dynamics and transcriptomes between sites, between reference and E2-treated animals, and between FSH-treated and nontreated animals. RESULTS We observed broad site-of-origin divergence in ovarian transcriptomes and reductions in ovarian follicle density between juvenile alligators from Lake Apopka and the reference site. Treating embryos from the reference site with E2 overwhelmingly recapitulated transcriptional and histological alterations observed in Lake Apopka juveniles. Ovarian phenotypes observed in Lake Apopka alligators or resulting from estrogen treatment were only partially rescued by treatment with exogenous FSH. DISCUSSION Recapitulation of ovarian abnormalities by precocious E2 revealed a relatively simple mechanism underlying contaminant-induced pathologies in a historical example of environmental endocrine disruption. Findings reported here support a model where the developmental timing of estrogen signaling has the potential to permanently alter ovarian organization and function. https://doi.org/10.1289/EHP6627.
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Affiliation(s)
- Matthew D. Hale
- Savannah River Ecology Laboratory, Aiken, South Carolina, USA
- Odum School of Ecology, University of Georgia, Athens, Georgia, USA
| | - Benjamin B. Parrott
- Savannah River Ecology Laboratory, Aiken, South Carolina, USA
- Odum School of Ecology, University of Georgia, Athens, Georgia, USA
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10
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Eklund RL, Knapp LC, Sandifer PA, Colwell RC. Oil Spills and Human Health: Contributions of the Gulf of Mexico Research Initiative. GEOHEALTH 2019; 3:391-406. [PMID: 32159026 PMCID: PMC7038885 DOI: 10.1029/2019gh000217] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 10/04/2019] [Accepted: 10/12/2019] [Indexed: 05/23/2023]
Abstract
The Gulf of Mexico Research Initiative (GoMRI) was established in 2010 with $500 million in funding provided by British Petroleum over a 10-year period to support research on the impacts of the Deepwater Horizon oil spill and recovery. Contributions of the GoMRI program to date focused on human health are presented in more than 32 peer-reviewed papers published between 2011 and May 2019. Primary findings from review of these papers are (i) the large quantity of dispersants used in the oil cleanup have been associated with human health concerns, including through obesogenicity, toxicity, and illnesses from aerosolization of the agents; (ii) oil contamination has been associated with potential for increases in harmful algal blooms and numbers of pathogenic Vibrio bacteria in oil-impacted waters; and (iii) members of Gulf communities who are heavily reliant upon natural resources for their livelihoods were found to be vulnerable to high levels of life disruptions and institutional distrust. Positive correlations include a finding that a high level of community attachment was beneficial for recovery. Actions taken to improve disaster response and reduce stress-associated health effects could lessen negative impacts of similar disasters in the future. Furthermore, GoMRI has supported annual conferences beginning in 2013 at which informative human health-related presentations have been made. Based on this review, it is recommended that the Oil Pollution Act of 1990 be updated to include enhanced funding for oil spill impacts to human health.
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Affiliation(s)
- Ruth L. Eklund
- Masters in Environmental and Sustainability Studies ProgramCollege of CharlestonCharlestonSCUSA
| | - Landon C. Knapp
- Center for Coastal Environmental and Human HealthCollege of CharlestonCharlestonSCUSA
| | - Paul A. Sandifer
- Center for Coastal Environmental and Human HealthCollege of CharlestonCharlestonSCUSA
| | - Rita C. Colwell
- University of MarylandMDUSA
- School of Public HealthJohns Hopkins UniversityBaltimoreMDUSA
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11
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Martínez-Juárez A, Moreno-Mendoza N. Mechanisms related to sexual determination by temperature in reptiles. J Therm Biol 2019; 85:102400. [PMID: 31657741 DOI: 10.1016/j.jtherbio.2019.102400] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 08/12/2019] [Accepted: 08/21/2019] [Indexed: 01/08/2023]
Abstract
A number of strategies have emerged that appear to relate to the evolution of mechanisms for sexual determination in vertebrates, among which are genetic sex determination caused by sex chromosomes and environmental sex determination, where environmental factors influence the phenotype of the sex of an individual. Within the reptile group, some orders such as: Chelonia, Crocodylia, Squamata and Rhynchocephalia, manifest one of the most intriguing and exciting environmental sexual determination mechanisms that exists, comprising temperature-dependent sex determination (TSD), where the temperature of incubation that the embryo experiences during its development is fundamental to establishing the sex of the individual. This makes them an excellent model for the study of sexual determination at the molecular, cellular and physiological level, as well as in terms of their implications at an evolutionary and ecological level. There are different hypotheses concerning how this process is triggered and this review aims to describe any new contributions to particular TSD hypotheses, analyzing them from the "eco-evo-devo" perspective.
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Affiliation(s)
- Adriana Martínez-Juárez
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apartado Postal 70228 México, D.F. 04510, Mexico
| | - Norma Moreno-Mendoza
- Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apartado Postal 70228 México, D.F. 04510, Mexico.
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12
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Hale MD, McCoy JA, Doheny BM, Galligan TM, Guillette LJ, Parrott BB. Embryonic estrogen exposure recapitulates persistent ovarian transcriptional programs in a model of environmental endocrine disruption†. Biol Reprod 2018; 100:149-161. [DOI: 10.1093/biolre/ioy165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 07/12/2018] [Indexed: 11/15/2022] Open
Affiliation(s)
- Matthew D Hale
- Savannah River Ecology Laboratory, Aiken, South Carolina, USA
- Odum School of Ecology, University of Georgia, Athens, Georgia, USA
| | | | - Brenna M Doheny
- School of Public Health, University of Minnesota, Minneapolis, Minnesota, USA
| | - Thomas M Galligan
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, Virginia, USA
| | - Louis J Guillette
- Marine Biomedicine and Environmental Sciences Program, Hollings Marine Laboratory, Medical University of South Carolina, Charleston, South Carolina, USA
- Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Benjamin B Parrott
- Savannah River Ecology Laboratory, Aiken, South Carolina, USA
- Odum School of Ecology, University of Georgia, Athens, Georgia, USA
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13
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17β-Estradiol modulates cell proliferation of medullary cords during ovarian differentiation of the Lepidochelys olivacea sea turtle. Dev Biol 2017; 431:263-271. [PMID: 28893547 DOI: 10.1016/j.ydbio.2017.09.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 09/06/2017] [Accepted: 09/06/2017] [Indexed: 11/23/2022]
Abstract
In turtles undergoing temperature sex determination (TSD), bipotential gonads express Sox9 in medullary cords at both female- (FPT) and male-producing temperatures (MPT). Subsequently, when the sex fate of medullary cords becomes dimorphic, at FPT, Sox9 is downregulated, whereas at MPT, its expression is maintained. Medullary cords in the ovary turn into ovarian lacuna, whereas in the testis they differentiate as seminiferous cords. When embryos of Lepidochelys olivacea sea turtle are incubated at MPT and treated with estradiol, Sox9 expression persists in the medullary cords in the form of tiny ovotestis-like formations. The perturbed development of the treated gonads is due to a significant decrease in the number of proliferating cells. This suggests that the disturbed effect caused by exogenous estradiol may be due to a conflict between the gene networks regulated by temperature and the increased level of endogenous estrogens, induced by the treatment. Here, we decided to use fadrozole and fulvestrant, an aromatase inhibitor and an estrogen-receptor antagonist, respectively, to provide insights into the role played by endogenous estrogens in regulating the cell proliferation of the two main gonadal compartments: the medullary cords and the cortex. Comparing cell proliferation patterns, our current results suggest that the endogenous estrogens are involved in determining the sex fate of medullary cords, by repressing proliferation. Interestingly, our results showed that endogenous estradiol levels are unnecessary for the thickening of the ovarian cortex.
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Rosenfeld CS, Denslow ND, Orlando EF, Gutierrez-Villagomez JM, Trudeau VL. Neuroendocrine disruption of organizational and activational hormone programming in poikilothermic vertebrates. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2017; 20:276-304. [PMID: 28895797 PMCID: PMC6174081 DOI: 10.1080/10937404.2017.1370083] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In vertebrates, sexual differentiation of the reproductive system and brain is tightly orchestrated by organizational and activational effects of endogenous hormones. In mammals and birds, the organizational period is typified by a surge of sex hormones during differentiation of specific neural circuits; whereas activational effects are dependent upon later increases in these same hormones at sexual maturation. Depending on the reproductive organ or brain region, initial programming events may be modulated by androgens or require conversion of androgens to estrogens. The prevailing notion based upon findings in mammalian models is that male brain is sculpted to undergo masculinization and defeminization. In absence of these responses, the female brain develops. While timing of organizational and activational events vary across taxa, there are shared features. Further, exposure of different animal models to environmental chemicals such as xenoestrogens such as bisphenol A-BPA and ethinylestradiol-EE2, gestagens, and thyroid hormone disruptors, broadly classified as neuroendocrine disrupting chemicals (NED), during these critical periods may result in similar alterations in brain structure, function, and consequently, behaviors. Organizational effects of neuroendocrine systems in mammals and birds appear to be permanent, whereas teleost fish neuroendocrine systems exhibit plasticity. While there are fewer NED studies in amphibians and reptiles, data suggest that NED disrupt normal organizational-activational effects of endogenous hormones, although it remains to be determined if these disturbances are reversible. The aim of this review is to examine how various environmental chemicals may interrupt normal organizational and activational events in poikilothermic vertebrates. By altering such processes, these chemicals may affect reproductive health of an animal and result in compromised populations and ecosystem-level effects.
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Affiliation(s)
- Cheryl S. Rosenfeld
- Department of Biomedical Sciences, University of Missouri, Columbia, MO, USA
- Thompson Center for Autism and Neurobehavioral Disorders, Columbia, MO, USA
- Bond Life Sciences Center, University of Missouri, Columbia, MO, USA
| | - Nancy D. Denslow
- Department of Physiological Sciences, University of Florida, Gainesville, FL, USA
- Center for Environmental and Human Toxicology, University of Florida, Gainesville, FL, USA
| | - Edward F. Orlando
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD, USA
| | | | - Vance L. Trudeau
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
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Guillette LJ, Parrott BB, Nilsson E, Haque MM, Skinner MK. Epigenetic programming alterations in alligators from environmentally contaminated lakes. Gen Comp Endocrinol 2016; 238:4-12. [PMID: 27080547 PMCID: PMC5064863 DOI: 10.1016/j.ygcen.2016.04.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/31/2016] [Accepted: 04/09/2016] [Indexed: 11/29/2022]
Abstract
Previous studies examining the reproductive health of alligators in Florida lakes indicate that a variety of developmental and health impacts can be attributed to a combination of environmental quality and exposures to environmental contaminants. The majority of these environmental contaminants have been shown to disrupt normal endocrine signaling. The potential that these environmental conditions and contaminants may influence epigenetic status and correlate to the health abnormalities was investigated in the current study. The red blood cell (RBC) (erythrocyte) in the alligator is nucleated so was used as an easily purified marker cell to investigate epigenetic programming. RBCs were collected from adult male alligators captured at three sites in Florida, each characterized by varying degrees of contamination. While Lake Woodruff (WO) has remained relatively pristine, Lake Apopka (AP) and Merritt Island (MI) convey exposures to different suites of contaminants. DNA was isolated and methylated DNA immunoprecipitation (MeDIP) was used to isolate methylated DNA that was then analyzed in a competitive hybridization using a genome-wide alligator tiling array for a MeDIP-Chip analysis. Pairwise comparisons of alligators from AP and MI to WO revealed alterations in the DNA methylome. The AP vs. WO comparison identified 85 differential DNA methylation regions (DMRs) with ⩾3 adjacent oligonucleotide tiling array probes and 15,451 DMRs with a single oligo probe analysis. The MI vs. WO comparison identified 75 DMRs with the ⩾3 oligo probe and 17,411 DMRs with the single oligo probe analysis. There was negligible overlap between the DMRs identified in AP vs. WO and MI vs. WO comparisons. In both comparisons DMRs were primarily associated with CpG deserts which are regions of low CpG density (1-2CpG/100bp). Although the alligator genome is not fully annotated, gene associations were identified and correlated to major gene class functional categories and pathways of endocrine relevance. Observations demonstrate that environmental quality may be associated with epigenetic programming and health status in the alligator. The epigenetic alterations may provide biomarkers to assess the environmental exposures and health impacts on these populations of alligators.
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Affiliation(s)
- Louis J Guillette
- Department of Obstetrics and Gynecology, Marine Biomedicine and Environmental Sciences Program, Medical University of South Carolina, Hollings Marine Laboratory, Charleston, SC 29412, USA
| | - Benjamin B Parrott
- Department of Obstetrics and Gynecology, Marine Biomedicine and Environmental Sciences Program, Medical University of South Carolina, Hollings Marine Laboratory, Charleston, SC 29412, USA
| | - Eric Nilsson
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA
| | - M M Haque
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA
| | - Michael K Skinner
- Center for Reproductive Biology, School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA.
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Rich AL, Phipps LM, Tiwari S, Rudraraju H, Dokpesi PO. The Increasing Prevalence in Intersex Variation from Toxicological Dysregulation in Fetal Reproductive Tissue Differentiation and Development by Endocrine-Disrupting Chemicals. ENVIRONMENTAL HEALTH INSIGHTS 2016; 10:163-171. [PMID: 27660460 PMCID: PMC5017538 DOI: 10.4137/ehi.s39825] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 06/16/2016] [Accepted: 06/20/2016] [Indexed: 06/06/2023]
Abstract
An increasing number of children are born with intersex variation (IV; ambiguous genitalia/hermaphrodite, pseudohermaphroditism, etc.). Evidence shows that endocrine-disrupting chemicals (EDCs) in the environment can cause reproductive variation through dysregulation of normal reproductive tissue differentiation, growth, and maturation if the fetus is exposed to EDCs during critical developmental times in utero. Animal studies support fish and reptile embryos exhibited IV and sex reversal when exposed to EDCs. Occupational studies verified higher prevalence of offspring with IV in chemically exposed workers (male and female). Chemicals associated with endocrine-disrupting ability in humans include organochlorine pesticides, poly-chlorinated biphenyls, bisphenol A, phthalates, dioxins, and furans. Intersex individuals may have concurrent physical disorders requiring lifelong medical intervention and experience gender dysphoria. An urgent need exists to determine which chemicals possess the greatest risk for IV and the mechanisms by which these chemicals are capable of interfering with normal physiological development in children.
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Affiliation(s)
- Alisa L. Rich
- University of North Texas Health Science Center, Department of Environmental and Occupational Health Science, Fort Worth, TX, USA
- World Health Organization Chemical Risk Assessment Network Member, Geneva, Switzerland
| | - Laura M. Phipps
- University of North Texas Health Science Center, Department of Environmental and Occupational Health Science, Fort Worth, TX, USA
| | - Sweta Tiwari
- University of North Texas Health Science Center, Department of Environmental and Occupational Health Science, Fort Worth, TX, USA
| | - Hemanth Rudraraju
- University of North Texas Health Science Center, Department of Environmental and Occupational Health Science, Fort Worth, TX, USA
| | - Philip O. Dokpesi
- University of North Texas Health Science Center, Department of Environmental and Occupational Health Science, Fort Worth, TX, USA
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Yatsu R, Miyagawa S, Kohno S, Parrott BB, Yamaguchi K, Ogino Y, Miyakawa H, Lowers RH, Shigenobu S, Guillette LJ, Iguchi T. RNA-seq analysis of the gonadal transcriptome during Alligator mississippiensis temperature-dependent sex determination and differentiation. BMC Genomics 2016; 17:77. [PMID: 26810479 PMCID: PMC4727388 DOI: 10.1186/s12864-016-2396-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Accepted: 01/14/2016] [Indexed: 11/26/2022] Open
Abstract
Background The American alligator (Alligator mississippiensis) displays temperature-dependent sex determination (TSD), in which incubation temperature during embryonic development determines the sexual fate of the individual. However, the molecular mechanisms governing this process remain a mystery, including the influence of initial environmental temperature on the comprehensive gonadal gene expression patterns occurring during TSD. Results Our characterization of transcriptomes during alligator TSD allowed us to identify novel candidate genes involved in TSD initiation. High-throughput RNA sequencing (RNA-seq) was performed on gonads collected from A. mississippiensis embryos incubated at both a male and a female producing temperature (33.5 °C and 30 °C, respectively) in a time series during sexual development. RNA-seq yielded 375.2 million paired-end reads, which were mapped and assembled, and used to characterize differential gene expression. Changes in the transcriptome occurring as a function of both development and sexual differentiation were extensively profiled. Forty-one differentially expressed genes were detected in response to incubation at male producing temperature, and included genes such as Wnt signaling factor WNT11, histone demethylase KDM6B, and transcription factor C/EBPA. Furthermore, comparative analysis of development- and sex-dependent differential gene expression revealed 230 candidate genes involved in alligator sex determination and differentiation, and early details of the suspected male-fate commitment were profiled. We also discovered sexually dimorphic expression of uncharacterized ncRNAs and other novel elements, such as unique expression patterns of HEMGN and ARX. Twenty-five of the differentially expressed genes identified in our analysis were putative transcriptional regulators, among which were MYBL2, MYCL, and HOXC10, in addition to conventional sex differentiation genes such as SOX9, and FOXL2. Inferred gene regulatory network was constructed, and the gene-gene and temperature-gene interactions were predicted. Conclusions Gonadal global gene expression kinetics during sex determination has been extensively profiled for the first time in a TSD species. These findings provide insights into the genetic framework underlying TSD, and expand our current understanding of the developmental fate pathways during vertebrate sex determination. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2396-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ryohei Yatsu
- Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan.
| | - Shinichi Miyagawa
- Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan. .,Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan.
| | - Satomi Kohno
- Department of Obstetrics and Gynecology, Medical University of South Carolina, and Marine Biomedicine and Environmental Science Center, Hollings Marine Laboratory, Charleston, SC, 29412, USA.
| | - Benjamin B Parrott
- Department of Obstetrics and Gynecology, Medical University of South Carolina, and Marine Biomedicine and Environmental Science Center, Hollings Marine Laboratory, Charleston, SC, 29412, USA.
| | - Katsushi Yamaguchi
- National Institute for Basic Biology, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan.
| | - Yukiko Ogino
- Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan. .,Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan.
| | - Hitoshi Miyakawa
- Center for Bioscience Research and Education, Utsunomiya University, 350 Mine-machi, Utsunomiya, Tochigi, 321-8505, Japan.
| | - Russell H Lowers
- Innovative Health Applications, Kennedy Space Center, Merritt Island, FL, 32899, USA.
| | - Shuji Shigenobu
- Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan. .,National Institute for Basic Biology, National Institutes of Natural Sciences, 38 Nishigonaka, Myodaiji, Okazaki, Aichi, 444-8585, Japan.
| | - Louis J Guillette
- Department of Obstetrics and Gynecology, Medical University of South Carolina, and Marine Biomedicine and Environmental Science Center, Hollings Marine Laboratory, Charleston, SC, 29412, USA.
| | - Taisen Iguchi
- Department of Basic Biology, Faculty of Life Science, SOKENDAI (Graduate University for Advanced Studies), 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan. .,Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi, 444-8787, Japan.
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McCoy JA, Parrott BB, Rainwater TR, Wilkinson PM, Guillette LJ. Incubation history prior to the canonical thermosensitive period determines sex in the American alligator. Reproduction 2015; 150:279-87. [DOI: 10.1530/rep-15-0155] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 07/16/2015] [Indexed: 11/08/2022]
Abstract
Despite the widespread occurrence of environmental sex determination (ESD) among vertebrates, our knowledge of the temporal dynamics by which environmental factors act on this process remains limited. In many reptiles, incubation temperature determines sex during a discrete developmental window just prior to and coincident with the differentiation of the gonads. Yet, there is substantial variation in sex ratios among different clutches of eggs incubated at identical temperatures during this period. Here, we test the hypothesis that temperatures experienced prior to the reported thermosensitive period for alligators (Alligator mississippiensis) can impact how the sex determination system responds to thermal cues later in development. Temperature shift experiments on eggs collected from the field within 24 h of oviposition were employed to decouple various maternal influences from thermal effects, and results demonstrate a previously undefined window of thermosensitivity occurring by stage 15 of embryonic development, six stages earlier than previously reported. We also examine the intrasexual expression of several male- and female-biased genes and show that while male-biased genes display no intrasexual differences, ovarian CYP19A1 (aromatase) transcript abundance differs by approximately twofold depending on thermal exposures experienced at early stages of embryonic development. These findings expand our understanding of the ESD in the alligator and provide the rationale for reevaluation of the temporal dynamics of sex determination in other crocodilians.
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Endogenous and exogenous estrogens during embryonic development affect timing of hatch and growth in the American alligator (Alligator mississippiensis). Comp Biochem Physiol B Biochem Mol Biol 2015; 184:10-8. [DOI: 10.1016/j.cbpb.2015.02.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 02/04/2015] [Accepted: 02/06/2015] [Indexed: 11/24/2022]
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Iungman JL, Somoza GM, Piña CI. Are Stress-Related Hormones Involved in the Temperature-Dependent Sex Determination of the Broad-Snouted Caiman? SOUTH AMERICAN JOURNAL OF HERPETOLOGY 2015. [DOI: 10.2994/sajh-d-14-00027.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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