1
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Breves JP, Shaughnessy CA. Endocrine control of gill ionocyte function in euryhaline fishes. J Comp Physiol B 2024:10.1007/s00360-024-01555-3. [PMID: 38739280 DOI: 10.1007/s00360-024-01555-3] [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: 01/08/2024] [Revised: 02/16/2024] [Accepted: 04/11/2024] [Indexed: 05/14/2024]
Abstract
The endocrine system is an essential regulator of the osmoregulatory organs that enable euryhaline fishes to maintain hydromineral balance in a broad range of environmental salinities. Because branchial ionocytes are the primary site for the active exchange of Na+, Cl-, and Ca2+ with the external environment, their functional regulation is inextricably linked with adaptive responses to changes in salinity. Here, we review the molecular-level processes that connect osmoregulatory hormones with branchial ion transport. We focus on how factors such as prolactin, growth hormone, cortisol, and insulin-like growth-factors operate through their cognate receptors to direct the expression of specific ion transporters/channels, Na+/K+-ATPases, tight-junction proteins, and aquaporins in ion-absorptive (freshwater-type) and ion-secretory (seawater-type) ionocytes. While these connections have historically been deduced in teleost models, more recently, increased attention has been given to understanding the nature of these connections in basal lineages. We conclude our review by proposing areas for future investigation that aim to fill gaps in the collective understanding of how hormonal signaling underlies ionocyte-based processes.
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Affiliation(s)
- Jason P Breves
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY, 12866, USA.
| | - Ciaran A Shaughnessy
- Department of Integrative Biology, Oklahoma State University, 501 Life Sciences West, Stillwater, OK, 74078, USA
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2
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Malintha GHT, Woo DW, Celino-Brady FT, Seale AP. Temperature modulates the osmosensitivity of tilapia prolactin cells. Sci Rep 2023; 13:20217. [PMID: 37980366 PMCID: PMC10657356 DOI: 10.1038/s41598-023-47044-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Accepted: 11/08/2023] [Indexed: 11/20/2023] Open
Abstract
In euryhaline fish, prolactin (Prl) plays an essential role in freshwater (FW) acclimation. In the euryhaline and eurythermal Mozambique tilapia, Oreochromis mossambicus, Prl cells are model osmoreceptors, recently described to be thermosensitive. To investigate the effects of temperature on osmoreception, we incubated Prl cells of tilapia acclimated to either FW or seawater (SW) in different combinations of temperatures (20, 26 and 32 °C) and osmolalities (280, 330 and 420 mOsm/kg) for 6 h. Release of both Prl isoforms, Prl188 and Prl177, increased in hyposmotic media and were further augmented with a rise in temperature. Hyposmotically-induced release of Prl188, but not Prl177, was suppressed at 20 °C. In SW fish, mRNA expression of prl188 increased with rising temperatures at lower osmolalities, while and prl177 decreased at 32 °C and higher osmolalities. In Prl cells of SW-acclimated tilapia incubated in hyperosmotic media, the expressions of Prl receptors, prlr1 and prlr2, and the stretch-activated Ca2+ channel, trpv4,decreased at 32 °C, suggesting the presence of a cellular mechanism to compensate for elevated Prl release. Transcription factors, pou1f1, pou2f1b, creb3l1, cebpb, stat3, stat1a and nfat1c, known to regulate prl188 and prl177, were also downregulated at 32 °C. Our findings provide evidence that osmoreception is modulated by temperature, and that both thermal and osmotic responses vary with acclimation salinity.
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Affiliation(s)
- G H T Malintha
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, 1955 East-West Road, Honolulu, HI, 96822, USA
| | - Daniel W Woo
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, 1955 East-West Road, Honolulu, HI, 96822, USA
| | - Fritzie T Celino-Brady
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, 1955 East-West Road, Honolulu, HI, 96822, USA
- Division of Genetics, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
| | - Andre P Seale
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, 1955 East-West Road, Honolulu, HI, 96822, USA.
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3
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Chang RJA, Celino-Brady FT, Seale AP. Changes in cortisol and corticosteroid receptors during dynamic salinity challenges in Mozambique tilapia. Gen Comp Endocrinol 2023; 342:114340. [PMID: 37364646 DOI: 10.1016/j.ygcen.2023.114340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 06/16/2023] [Accepted: 06/23/2023] [Indexed: 06/28/2023]
Abstract
In estuarine environments, euryhaline fish maintain a narrow range of internal osmolality despite daily changes in environmental salinity that can range from fresh water (FW) to seawater (SW). The capacity of euryhaline fish to maintain homeostasis in a range of environmental salinities is primarily facilitated by the neuroendocrine system. One such system, the hypothalamic-pituitary-interrenal (HPI) axis, culminates in the release of corticosteroids such as cortisol into circulation. Cortisol functions as both a mineralocorticoid and glucocorticoid in fish because of its roles in osmoregulation and metabolism, respectively. The gill, a key site for osmoregulation, and the liver, the primary storage site for glucose, are known targets of cortisol's actions during salinity stress. While cortisol facilitates acclimation to SW environments, less is known on its role during FW adaptation. In this study, we characterized the responses of plasma cortisol, mRNA expression of pituitary pro-opiomelanocortin (pomc), and mRNA expression of liver and gill corticosteroid receptors (gr1, gr2, and mr) in the euryhaline Mozambique tilapia (Oreochromis mossambicus) under salinity challenges. Specifically, tilapia were subjected to salinity transfer regimes from steady-state FW to SW, SW to FW (experiment 1) or steady state FW or SW to tidal regimen (TR, experiment 2). In experiment 1, fish were sampled at 0 h, 6 h, 1, 2, and 7 d post transfer; while in experiment 2, fish were sampled at day 0 and day 15. We found a rise in pituitary pomc expression and plasma cortisol following transfer to SW while branchial corticosteroid receptors were immediately downregulated after transfer to FW. Moreover, branchial expression of corticosteroid receptors changed with each salinity phase of the TR, suggesting rapid environmental modulation of corticosteorid action. Together, these results support the role of the HPI-axis in promoting salinity acclimation, including in dynamically-changing environments.
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Affiliation(s)
- Ryan J A Chang
- Department of Human Nutrition, Food, and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA
| | - Fritzie T Celino-Brady
- Department of Human Nutrition, Food, and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA
| | - Andre P Seale
- Department of Human Nutrition, Food, and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
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4
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Hewage TMG, Woo DW, Celino-Brady FT, Seale AP. Temperature modulates the osmosensitivity of tilapia prolactin cells. RESEARCH SQUARE 2023:rs.3.rs-2524830. [PMID: 36909603 PMCID: PMC10002831 DOI: 10.21203/rs.3.rs-2524830/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
In euryhaline fish, prolactin (Prl) plays an essential role in freshwater (FW) acclimation. In the euryhaline and eurythermal Mozambique tilapia, Oreochromis mossambicus, Prl cells are model osmoreceptors, recently described to be thermosensitive. To investigate the effects of temperature on osmoreception, we incubated Prl cells of tilapia acclimated to either FW or seawater (SW) in different temperature (20, 26 and 32°C) and osmolality (280, 330 and 420 mOsm/kg) combinations for 6 h. Release of both Prl isoforms, Prl188 and Prl177, increased in hyposmotic media and were further augmented with a rise in temperature. Hyposmotically-induced release of Prl188 was inhibited at 20°C. In SW fish, mRNA expression of prl188 and prl177 showed direct and inverse relationships with temperature, respectively. In SW-acclimated tilapia Prl cells incubated in hyperosmotic media, Prl receptors, prlr1 and prlr2, and the stretch-activated Ca2+ channel, trpv4, were inhibited at 32°C, suggesting the presence of a cellular mechanism to compensate for elevated Prl release. Transcription factors, pou1f1, pou2f1b, creb3l1, cebpb, stat3, stat1a and nfat1c, known to regulate prl188 and prl177, were also downregulated at 32°C. Our findings provide evidence that osmoreception is modulated by temperature, and that both thermal and osmotic responses vary with acclimation salinity.
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5
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Seale AP, Breves JP. Endocrine and osmoregulatory responses to tidally-changing salinities in fishes. Gen Comp Endocrinol 2022; 326:114071. [PMID: 35697315 DOI: 10.1016/j.ygcen.2022.114071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 06/06/2022] [Accepted: 06/07/2022] [Indexed: 12/15/2022]
Abstract
Salinity is one of the main physical properties that govern the distribution of fishes across aquatic habitats. In order to maintain their body fluids near osmotic set points in the face of salinity changes, euryhaline fishes rely upon tissue-level osmotically-induced responses and systemic endocrine signaling to direct adaptive ion-transport processes in the gill and other critical osmoregulatory organs. Some euryhaline teleosts inhabit tidally influenced waters such as estuaries where salinity can vary between fresh water (FW) and seawater (SW). The physiological adaptations that underlie euryhalinity in teleosts have been traditionally identified in fish held under steady-state conditions or following unidirectional transfers between FW and SW. Far fewer studies have employed salinity regimes that simulate the tidal cycles that some euryhaline fishes may experience in their native habitats. With an emphasis on prolactin (Prl) signaling and branchial ionocytes, this mini-review contrasts the physiological responses between euryhaline fish responding to tidal versus unidirectional changes in salinity. Three patterns that emerged from studying Mozambique tilapia (Oreochromis mossambicus) subjected to tidally-changing salinities include, 1) fish can compensate for continuous and marked changes in external salinity to maintain osmoregulatory parameters within narrow ranges, 2) tilapia maintain branchial ionocyte populations in a fashion similar to SW-acclimated fish, and 3) there is a shift from systemic to local modulation of Prl signaling.
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Affiliation(s)
- Andre P Seale
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, 1955 East-West Road, Honolulu, HI 96822, USA.
| | - Jason P Breves
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA
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6
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Breves JP, Puterbaugh KM, Bradley SE, Hageman AE, Verspyck AJ, Shaw LH, Danielson EC, Hou Y. Molecular targets of prolactin in mummichogs (Fundulus heteroclitus): Ion transporters/channels, aquaporins, and claudins. Gen Comp Endocrinol 2022; 325:114051. [PMID: 35533740 DOI: 10.1016/j.ygcen.2022.114051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/25/2022] [Accepted: 05/02/2022] [Indexed: 11/30/2022]
Abstract
Prolactin (Prl) was identified over 60 years ago in mummichogs (Fundulus heteroclitus) as a "freshwater (FW)-adapting hormone", yet the cellular and molecular targets of Prl in this model teleost have remained unknown. Here, we conducted a phylogenetic analysis of two mummichog Prl receptors (Prlrs), designated Prlra and Prlrb, prior to describing the tissue- and salinity-dependent expression of their associated mRNAs. We then administered ovine Prl (oPrl) to mummichogs held in brackish water and characterized the expression of genes associated with FW- and seawater (SW)-type ionocytes. Within FW-type ionocytes, oPrl stimulated the expression of Na+/Cl- cotransporter 2 (ncc2) and aquaporin 3 (aqp3). Alternatively, branchial Na+/H+ exchanger 2 and -3 (nhe2 and -3) expression did not respond to oPrl. Gene transcripts associated with SW-type ionocytes, including Na+/K+/2Cl- cotransporter 1 (nkcc1), cystic fibrosis transmembrane regulator 1 (cftr1), and claudin 10f (cldn10f) were reduced by oPrl. Isolated gill filaments incubated with oPrl in vitro exhibited elevated ncc2 and prlra expression. Given the role of Aqps in supporting gastrointestinal fluid absorption, we assessed whether several intestinal aqp transcripts were responsive to oPrl and found that aqp1a and -8 levels were reduced by oPrl. Our collective data indicate that Prl promotes FW-acclimation in mummichogs by orchestrating the expression of solute transporters/channels, water channels, and tight-junction proteins across multiple osmoregulatory organs.
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Affiliation(s)
- Jason P Breves
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA.
| | - Katie M Puterbaugh
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA
| | - Serena E Bradley
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA
| | - Annie E Hageman
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA
| | - Adrian J Verspyck
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA
| | - Lydia H Shaw
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA
| | - Elizabeth C Danielson
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA
| | - Yubo Hou
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY 12866, USA
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7
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Inokuchi M, Yamaguchi Y, Moorman BP, Seale AP. Age-Dependent Decline in Salinity Tolerance in a Euryhaline Fish. FRONTIERS IN AGING 2022; 2:675395. [PMID: 35822031 PMCID: PMC9261306 DOI: 10.3389/fragi.2021.675395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/12/2021] [Indexed: 12/18/2022]
Abstract
Euryhaline teleost fish are characterized by their ability to tolerate a wide range of environmental salinities by modifying the function of osmoregulatory cells and tissues. In this study, we experimentally addressed the age-related decline in the sensitivity of osmoregulatory transcripts associated with a transfer from fresh water (FW) to seawater (SW) in the euryhaline teleost, Mozambique tilapia, Oreochromis mossambicus. The survival rates of tilapia transferred from FW to SW were inversely related with age, indicating that older fish require a longer acclimation period during a salinity challenge. The relative expression of Na+/K+/2Cl− cotransporter 1a (nkcc1a), which plays an important role in hyposmoregulation, was significantly upregulated in younger fish after SW transfer, indicating a clear effect of age in the sensitivity of branchial ionocytes. Prolactin (Prl), a hyperosmoregulatory hormone in O. mossambicus, is released in direct response to a fall in extracellular osmolality. Prl cells of 4-month-old tilapia were sensitive to hyposmotic stimuli, while those of >24-month-old fish did not respond. Moreover, the responsiveness of branchial ionocytes to Prl was more robust in younger fish. Taken together, multiple aspects of osmotic homeostasis, from osmoreception to hormonal and environmental control of osmoregulation, declined in older fish. This decline appears to undermine the ability of older fish to survive transfer to hyperosmotic environments.
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Affiliation(s)
- Mayu Inokuchi
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Tokyo, Japan
| | - Yoko Yamaguchi
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Japan
| | - Benjamin P Moorman
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kaneohe, HI, United States
| | - Andre P Seale
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kaneohe, HI, United States.,Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI, United States
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8
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Pavlova NS, Gizatulina AR, Neretina TV, Smirnova OV. Expression of Opsin Genes in the Retina of Female and Male Three-Spined Sticklebacks Gasterosteus aculeatus L.: Effect of Freshwater Adaptation and Prolactin Administration. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:215-224. [PMID: 35526850 DOI: 10.1134/s0006297922030038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 01/24/2022] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
Color vision sensitivity is crucial for fish adaptation during migration and reproduction. Prolactin and prolactin-like hormone are important regulators in both these processes. We hypothesized that prolactin influences the color vision sensitivity during freshwater migrations in fish. We studied the effects of prolactin and freshwater adaptation during the spawning period on the expression of opsin genes (SWS1, SWS2, RH2, LWS) in the retina of female and male three-spined sticklebacks Gasterosteus aculeatus L. Expression of the prolactin gene increased in the brain of females, but not males, while expression of the prolactin-like hormone decreased in the brain of both male and female sticklebacks during freshwater adaptation. Expression of the SWS2 gene decreased in the retina of females and males during freshwater adaptation and after prolactin administration. Expression of the SWS1 gene decreased in the retina of male sticklebacks after prolactin administration, but not during freshwater adaptation. Expression of the RH2 and LWS genes did not depend on prolactin administration in male and female sticklebacks. We conclude that expression of some opsin genes in the retina of sticklebacks is regulated by prolactin and depends on sex and freshwater adaptation. This expands our knowledge of the adaptive effects of prolactin on fish during freshwater migrations.
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Affiliation(s)
- Nadezhda S Pavlova
- Department of Human and Animal Physiology, Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia.
| | - Albina R Gizatulina
- Department of Physiology and General Pathology, Faculty of Fundamental Medicine, Lomonosov Moscow State University, Moscow, 119991, Russia
| | - Tatyana V Neretina
- Pertsov White Sea Biological Station, Moscow State University, 186671 Loukhsky District, Republic of Karelia, Russia
| | - Olga V Smirnova
- Department of Human and Animal Physiology, Faculty of Biology, Lomonosov Moscow State University, Moscow, 119991, Russia
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9
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Uchiyama Y, Iwasa Y, Yamaguchi S. Optimal composition of chloride cells for osmoregulation in a randomly fluctuating environment. J Theor Biol 2022; 537:111016. [PMID: 35026211 DOI: 10.1016/j.jtbi.2022.111016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/01/2021] [Accepted: 01/05/2022] [Indexed: 11/19/2022]
Abstract
Fish live in water with a different osmotic pressure from that in the body. Their gills have chloride cells that transport ions to maintain an appropriate level of osmotic pressure in the body. The direction of ion transport is different between seawater and freshwater. There are two types of chloride cells that specialize in unidirectional transport and generalist cells that can switch their function quickly in response to environmental salinity. In species that experience salinity changes throughout life (euryhaline species), individuals may replace some chloride cells with cells of different types upon a sudden change in environmental salinity. In this paper, we develop a dynamic optimization model for the chloride cell composition of an individual living in an environment with randomly fluctuating salinity. The optimal solution is to minimize the sum of the workload of chloride cells in coping with the difference in osmotic pressure, the maintenance cost, and the temporal cost due to environmental change. The optimal fraction of generalist chloride cells increases with the frequency of salinity changes and the time needed for new cells to be fully functional but decreases with excess maintenance cost.
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Affiliation(s)
- Yuka Uchiyama
- Division of Mathematical Sciences, Tokyo Woman's Christian University, 2-6-1 Zempukuji, Suginami-ku, Tokyo 167-8585, Japan
| | - Yoh Iwasa
- Department of Biology, Kyushu University, Motooka 744, Nishi-ku, Fukuoka 819-0395, Japan; Institute of Freshwater Biology, Nagano University, 1088 Komaki, Ueda, Nagano 386-0031, Japan
| | - Sachi Yamaguchi
- Division of Mathematical Sciences, Tokyo Woman's Christian University, 2-6-1 Zempukuji, Suginami-ku, Tokyo 167-8585, Japan.
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10
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Seale LA, Gilman CL, Zavacki AM, Larsen PR, Inokuchi M, Breves JP, Seale AP. Regulation of thyroid hormones and branchial iodothyronine deiodinases during freshwater acclimation in tilapia. Mol Cell Endocrinol 2021; 538:111450. [PMID: 34506867 PMCID: PMC8551029 DOI: 10.1016/j.mce.2021.111450] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 08/24/2021] [Accepted: 09/01/2021] [Indexed: 10/20/2022]
Abstract
Euryhaline fishes are capable of maintaining osmotic homeostasis in a wide range of environmental salinities. Several pleiotropic hormones, including prolactin, growth hormone, and thyroid hormones (THs) are mediators of salinity acclimation. It is unclear, however, the extent to which THs and the pituitary-thyroid axis promote the adaptive responses of key osmoregulatory organs to freshwater (FW) environments. In the current study, we characterized circulating thyroxine (T4) and 3-3'-5-triiodothyronine (T3) levels in parallel with the outer ring deiodination (ORD) activities of deiodinases (dios) and mRNA expression of dio1, dio2, and dio3 in gill during the acclimation of Mozambique tilapia (Oreochromis mossambicus) to FW. Tilapia transferred from seawater (SW) to FW exhibited reduced plasma T4 and T3 levels at 6 h. These reductions coincided with an increase in branchial dio2-like activity and decreased branchial dio1 gene expression. To assess whether dios respond to osmotic conditions and/or systemic signals, gill filaments were exposed to osmolalities ranging from 280 to 450 mOsm/kg in an in vitro incubation system. Gene expression of branchial dio1, dio2, and dio3 was not directly affected by extracellular osmotic conditions. Lastly, we observed that dio1 and dio2 expression was stimulated by thyroid-stimulating hormone in hypophysectomized tilapia, suggesting that branchial TH metabolism is regulated by systemic signals. Our collective findings suggest that THs are involved in the FW acclimation of Mozambique tilapia through their interactions with branchial deiodinases that modulate their activities in a key osmoregulatory organ.
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Affiliation(s)
- Lucia A Seale
- Pacific Biosciences Research Center, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, 1933 East-West Road, Honolulu, HI, 96822, USA
| | - Christy L Gilman
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai'i at Mānoa, 651 Ilalo Street, Honolulu, HI, 96813, USA
| | - Ann Marie Zavacki
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - P Reed Larsen
- Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Mayu Inokuchi
- Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo, Tokyo, 113-8657, Japan
| | - Jason P Breves
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY, 12866, USA
| | - Andre P Seale
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, 1955 East-West Road, Honolulu, HI, 96822, USA.
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11
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Vargas-Chacoff L, Dann F, Paschke K, Oyarzún-Salazar R, Nualart D, Martínez D, Wilson JM, Guerreiro PM, Navarro JM. Freshening effect on the osmotic response of the Antarctic spiny plunderfish Harpagifer antarcticus. JOURNAL OF FISH BIOLOGY 2021; 98:1558-1571. [PMID: 33452810 DOI: 10.1111/jfb.14676] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 01/05/2021] [Accepted: 01/14/2021] [Indexed: 06/12/2023]
Abstract
Global warming is having a significant impact around the world, modifying environmental conditions in many areas, including in zones that have been thermally stable for thousands of years, such as Antarctica. Stenothermal sedentary intertidal fish species may suffer due to warming, notably if this causes water freshening from increased freshwater inputs. Acute decreases in salinity, from 33 down to 5, were used to assess osmotic responses to environmental salinity fluctuations in Antarctic spiny plunderfish Harpagifer antarcticus, in particular to evaluate if H. antarcticus is able to cope with freshening and to describe osmoregulatory responses at different levels (haematological variables, muscle water content, gene expression, NKA activity). H. antarcticus were acclimated to a range of salinities (33 as control, 20, 15, 10 and 5) for 1 week. At 5, plasma osmolality and calcium concentration were both at their lowest, while plasma cortisol and percentage muscle water content were at their highest. At the same salinity, gill and intestine Na+ -K+ -ATPase (NKA) activities were at their lowest and highest, respectively. In kidney, NKA activity was highest at intermediate salinities (15 and 10). The salinity-dependent NKA mRNA expression patterns differed depending on the tissue. Marked changes were also observed in the expression of genes coding membrane proteins associated with ion and water transport, such as NKCC2, CFTR and AQP8, and in the expression of mRNA for the regulatory hormone prolactin (PRL) and its receptor (PRLr). Our results demonstrate that freshening causes osmotic imbalances in H. antarcticus, apparently due to reduced capacity of both transport and regulatory mechanisms of key organs to maintain homeostasis. This has implications for fish species that have evolved in stable environmental conditions in the Antarctic, now threatened by climate change.
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Affiliation(s)
- Luis Vargas-Chacoff
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
- Centro Fondap de Investigación de Altas Latitudes, Universidad Austral de Chile, Valdivia, Chile
| | - Francisco Dann
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
- Centro Fondap de Investigación de Altas Latitudes, Universidad Austral de Chile, Valdivia, Chile
| | - Kurt Paschke
- Centro Fondap de Investigación de Altas Latitudes, Universidad Austral de Chile, Valdivia, Chile
- Instituto de Acuicultura, Universidad Austral de Chile, Puerto Montt, Chile
| | - Ricardo Oyarzún-Salazar
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
- Centro Fondap de Investigación de Altas Latitudes, Universidad Austral de Chile, Valdivia, Chile
- Escuela de Graduados Programa de Doctorado en Ciencias de la Acuicultura, Universidad Austral de Chile, Puerto Montt, Chile
| | - Daniela Nualart
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
| | - Danixa Martínez
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
| | - Jonathan M Wilson
- Wilfrid Laurier University, Waterloo, Ontario, Canada
- Centro Interdisciplinar de Investigação Marinha e Ambiental, Matosinhos, Portugal
| | | | - Jorge M Navarro
- Instituto de Ciencias Marinas y Limnológicas, Universidad Austral de Chile, Valdivia, Chile
- Centro Fondap de Investigación de Altas Latitudes, Universidad Austral de Chile, Valdivia, Chile
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12
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Powell D, Ngo PT, Nguyen HN, Knibb W, Elizur A. Transcriptomic responses of saline-adapted Nile tilapia (Oreochromis niloticus) to rearing in both saline and freshwater. Mar Genomics 2021; 60:100879. [PMID: 34023275 DOI: 10.1016/j.margen.2021.100879] [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: 06/10/2020] [Revised: 03/26/2021] [Accepted: 05/12/2021] [Indexed: 11/25/2022]
Abstract
The Nile tilapia, Oreochromis niloticus, is an important species for global aquaculture. Recently, a single genetic line of Nile tilapia was developed using estimated breeding values (EBVs) for body weight under moderately saline water that showed significant improvement in growth performance. To explore the molecular mechanisms underlying this enhanced growth capacity, RNA-Seq was used to profile differences in gene expression in the liver and pituitary gland of high- and low-growth performance families of male Nile tilapia progeny, reared in either saline or freshwater environments. Comparisons of tissues from high- and low-EBV families, and also between fish reared in either saline or freshwater, revealed 142 and 2208 differentially expressed genes (DEGs), respectively. DEGs identified between the EBV groups comprised a number of genes involved in the regulation of growth and reproduction. We found an overexpression of hormone genes involved in growth-inhibition in the pituitary of Low-EBV tilapia including 2 somatostatin genes (GHIH), corticoliberin (CRH) and tachykinin-3-like protein. Furthermore, several genes associated with the cAMP pathway were underexpressed in low-EBV tilapia pituitary together with several early response genes. This study provides insight into the transcriptomic factors associated with growth performance in saline-adapted Nile tilapia reared in environments with high and low salinity levels and provides valuable knowledge for the future development of selection strategies to improve growth performance in this species.
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Affiliation(s)
- Daniel Powell
- Department of Biology, Lund University, 223 62 Lund, Sweden; Centre for Genetics, Ecology and Physiology, University of the Sunshine Coast, Sippy Downs, Queensland 4558, Australia.
| | - Phu Thoa Ngo
- Centre for Genetics, Ecology and Physiology, University of the Sunshine Coast, Sippy Downs, Queensland 4558, Australia; Mavin Aquaculture, Mavin Group, Hudland Tower Building, No. 6 Nguyen Huu Tho, Hoang Liet Ward, Hoang Mai District, Hanoi, Viet Nam; Research Institute for Aquaculture No.1, Dinh Bang, Tu Son, Bac Ninh, Viet Nam.
| | - Hong Nguyen Nguyen
- Centre for Genetics, Ecology and Physiology, University of the Sunshine Coast, Sippy Downs, Queensland 4558, Australia.
| | - Wayne Knibb
- Centre for Genetics, Ecology and Physiology, University of the Sunshine Coast, Sippy Downs, Queensland 4558, Australia.
| | - Abigail Elizur
- Centre for Genetics, Ecology and Physiology, University of the Sunshine Coast, Sippy Downs, Queensland 4558, Australia.
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13
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Shaughnessy CA, Breves JP. Molecular mechanisms of Cl
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transport in fishes: New insights and their evolutionary context. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2020; 335:207-216. [DOI: 10.1002/jez.2428] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/28/2020] [Accepted: 10/29/2020] [Indexed: 12/13/2022]
Affiliation(s)
| | - Jason P. Breves
- Department of Biology Skidmore College Saratoga Springs New York USA
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14
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Seale AP, Malintha GHT, Celino-Brady FT, Head T, Belcaid M, Yamaguchi Y, Lerner DT, Baltzegar DA, Borski RJ, Stoytcheva ZR, Breves JP. Transcriptional regulation of prolactin in a euryhaline teleost: Characterisation of gene promoters through in silico and transcriptome analyses. J Neuroendocrinol 2020; 32:e12905. [PMID: 32996203 PMCID: PMC8612711 DOI: 10.1111/jne.12905] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 07/31/2020] [Accepted: 08/26/2020] [Indexed: 12/20/2022]
Abstract
The sensitivity of prolactin (Prl) cells of the Mozambique tilapia (Oreochromis mossambicus) pituitary to variations in extracellular osmolality enables investigations into how osmoreception underlies patterns of hormone secretion. Through the actions of their main secretory products, Prl cells play a key role in supporting hydromineral balance of fishes by controlling the major osmoregulatory organs (ie, gill, intestine and kidney). The release of Prl from isolated cells of the rostral pars distalis (RPD) occurs in direct response to physiologically relevant reductions in extracellular osmolality. Although the particular signal transduction pathways that link osmotic conditions to Prl secretion have been identified, the processes that underlie hyposmotic induction of prl gene expression remain unknown. In this short review, we describe two distinct tilapia gene loci that encode Prl177 and Prl188 . From our in silico analyses of prl177 and prl188 promoter regions (approximately 1000 bp) and a transcriptome analysis of RPDs from fresh water (FW)- and seawater (SW)-acclimated tilapia, we propose a working model for how multiple transcription factors link osmoreceptive processes with adaptive patterns of prl177 and prl188 gene expression. We confirmed via RNA-sequencing and a quantitative polymerase chain reaction that multiple transcription factors emerging as predicted regulators of prl gene expression are expressed in the RPD of tilapia. In particular, gene transcripts encoding pou1f1, stat3, creb3l1, pbxip1a and stat1a were highly expressed; creb3l1, pbxip1a and stat1a were elevated in fish acclimated to SW vs FW. Combined, our in silico and transcriptome analyses set a path for resolving how adaptive patterns of Prl secretion are achieved via the integration of osmoreceptive processes with the control of prl gene transcription.
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Affiliation(s)
- Andre P. Seale
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai’i at Mānoa, Honolulu, HI, USA
| | | | - Fritzie T. Celino-Brady
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai’i at Mānoa, Honolulu, HI, USA
| | - Tony Head
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai’i at Mānoa, Honolulu, HI, USA
| | - Mahdi Belcaid
- Hawai’i Institute of Marine Biology, University of Hawai’i at Mānoa, Kaneohe, HI, USA
| | - Yoko Yamaguchi
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Japan
| | - Darren T. Lerner
- University of Hawai’i Sea Grant College Program, University of Hawai’i at Mānoa, Honolulu, HI, USA
| | - David A. Baltzegar
- Genomic Sciences Laboratory, Office of Research and Innovation, North Carolina State University, Raleigh, NC, USA
| | - Russell J. Borski
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Zoia R. Stoytcheva
- Department of Human Nutrition, Food and Animal Sciences, University of Hawai’i at Mānoa, Honolulu, HI, USA
| | - Jason P. Breves
- Department of Biology, Skidmore College, Saratoga Springs, NY, USA
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15
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Introducing the Amphibious Mudskipper Goby as a Unique Model to Evaluate Neuro/Endocrine Regulation of Behaviors Mediated by Buccal Sensation and Corticosteroids. Int J Mol Sci 2020; 21:ijms21186748. [PMID: 32938015 PMCID: PMC7555618 DOI: 10.3390/ijms21186748] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/04/2020] [Accepted: 09/08/2020] [Indexed: 11/19/2022] Open
Abstract
Some fish have acquired the ability to breathe air, but these fish can no longer flush their gills effectively when out of water. Hence, they have developed characteristic means for defense against external stressors, including thirst (osmolarity/ions) and toxicity. Amphibious fish, extant air-breathing fish emerged from water, may serve as models to examine physiological responses to these stressors. Some of these fish, including mudskipper gobies such as Periophthalmodon schlosseri, Boleophthalmus boddarti and our Periophthalmus modestus, display distinct adaptational behaviors to these factors compared with fully aquatic fish. In this review, we introduce the mudskipper goby as a unique model to study the behaviors and the neuro/endocrine mechanisms of behavioral responses to the stressors. Our studies have shown that a local sensation of thirst in the buccal cavity—this being induced by dipsogenic hormones—motivates these fish to move to water through a forebrain response. The corticosteroid system, which is responsive to various stressors, also stimulates migration, possibly via the receptors in the brain. We suggest that such fish are an important model to deepen insights into the stress-related neuro/endocrine-behavioral effects.
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16
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Sun Z, Lou F, Zhang Y, Song N. Gill Transcriptome Sequencing and De Novo Annotation of Acanthogobius ommaturus in Response to Salinity Stress. Genes (Basel) 2020; 11:genes11060631. [PMID: 32521805 PMCID: PMC7349121 DOI: 10.3390/genes11060631] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 05/23/2020] [Accepted: 06/04/2020] [Indexed: 01/17/2023] Open
Abstract
Acanthogobius ommaturus is a euryhaline fish widely distributed in coastal, bay and estuarine areas, showing a strong tolerance to salinity. In order to understand the mechanism of adaptation to salinity stress, RNA-seq was used to compare the transcriptome responses of Acanthogobius ommaturus to the changes of salinity. Four salinity gradients, 0 psu, 15 psu (control), 30 psu and 45 psu were set to conduct the experiment. In total, 131,225 unigenes were obtained from the gill tissue of A. ommaturus using the Illumina HiSeq 2000 platform (San Diego, USA). Compared with the gene expression profile of the control group, 572 differentially expressed genes (DEGs) were screened, with 150 at 0 psu, 170 at 30 psu, and 252 at 45 psu. Additionally, among these DEGs, Gene Ontology (GO) analysis indicated that binding, metabolic processes and cellular processes were significantly enriched. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis detected 3, 5 and 8 pathways related to signal transduction, metabolism, digestive and endocrine systems at 0 psu, 30 psu and 45 psu, respectively. Based on GO enrichment analysis and manual literature searches, the results of the present study indicated that A. ommaturus mainly responded to energy metabolism, ion transport and signal transduction to resist the damage caused by salinity stress. Eight DEGs were randomly selected for further validation by quantitative real-time PCR (qRT-PCR) and the results were consistent with the RNA-seq data.
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Affiliation(s)
| | | | | | - Na Song
- Correspondence: or ; Tel.: +86-532-820-31658
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17
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Breves JP, Starling JA, Popovski CM, Doud JM, Tipsmark CK. Salinity-dependent expression of ncc2 in opercular epithelium and gill of mummichog (Fundulus heteroclitus). J Comp Physiol B 2020; 190:219-230. [PMID: 31980891 DOI: 10.1007/s00360-020-01260-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 12/20/2019] [Accepted: 01/09/2020] [Indexed: 02/06/2023]
Abstract
Mummichogs (Fundulus heteroclitus) can tolerate abrupt changes in environmental salinity because of their ability to rapidly adjust the activities of ionocytes in branchial and opercular epithelia. In turn, the concerted expression of sub-cellular effectors of ion transport underlies adaptive responses to fluctuating salinities. Exposure to seawater (SW) stimulates the expression of Na+/K+/2Cl- cotransporter 1 (nkcc1) and cystic fibrosis transmembrane regulator (cftr) mRNAs in support of ion extrusion by SW-type ionocytes. Given the incomplete understanding of how freshwater (FW)-type ionocytes actually operate in mummichogs, the transcriptional responses essential for ion absorption in FW environments remain unresolved. In a subset of species, a 'fish-specific' Na+/Cl- cotransporter denoted Ncc2 (Slc12a10) is responsible for the uptake of Na+ and Cl- across the apical surface of FW-type ionocytes. In the current study, we identified an ncc2 transcript that is highly expressed in gill filaments and opercular epithelium of FW-acclimated mummichogs. Within 1 day of transfer from SW to FW, ncc2 levels in both tissues increased in parallel with reductions in nkcc1 and cftr. Conversely, mummichogs transferred from FW to SW exhibited marked reductions in ncc2 concurrent with increases in nkcc1 and cftr. Immunohistochemical analyses employing a homologous antibody revealed apical Ncc2-immunoreactivity in Na+/K+-ATPase-immunoreactive ionocytes of FW-acclimated animals. Our combined observations suggest that Ncc2/ncc2-expressing ionocytes support the capacity of mummichogs to inhabit FW environments.
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Affiliation(s)
- Jason P Breves
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY, 12866, USA.
| | - Julie A Starling
- Department of Biological Sciences, University of Arkansas, Fayetteville, AK, 72701, USA
| | - Christine M Popovski
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY, 12866, USA
| | - James M Doud
- Department of Biology, Skidmore College, 815 N. Broadway, Saratoga Springs, NY, 12866, USA
| | - Christian K Tipsmark
- Department of Biological Sciences, University of Arkansas, Fayetteville, AK, 72701, USA
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18
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Seale AP, Pavlosky KK, Celino-Brady FT, Yamaguchi Y, Breves JP, Lerner DT. Systemic versus tissue-level prolactin signaling in a teleost during a tidal cycle. J Comp Physiol B 2019; 189:581-594. [PMID: 31485757 DOI: 10.1007/s00360-019-01233-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 08/05/2019] [Accepted: 08/21/2019] [Indexed: 12/14/2022]
Abstract
Euryhaline Mozambique tilapia (Oreochromis mossambicus) are native to estuaries where they encounter tidal fluctuations in environmental salinity. These fluctuations can be dramatic, subjecting individuals to salinities characteristic of fresh water (FW < 0.5‰) and seawater (SW 35‰) within a single tidal cycle. In the current study, we reared tilapia under a tidal regimen that simulated the dynamic conditions of their native habitat. Tilapia were sampled every 3 h over a 24 h period to temporally resolve how prolactin (PRL) signaling is modulated in parallel with genes encoding branchial effectors of osmoregulation. The following parameters were measured: plasma osmolality, plasma PRL177 and PRL188 concentrations, pituitary prl177 and prl188 gene expression, and branchial prl receptor (prlr1 and prlr2), Na+/Cl--cotransporter (ncc2), Na+/K+/2Cl--cotransporter (nkcc1a), Na+/K+-ATPase (nkaα1a and nkaα1b), cystic fibrosis transmembrane regulator (cftr), and aquaporin 3 (aqp3) gene expression. Throughout the 24 h sampling period, plasma osmolality reflected whether tilapia were sampled during the FW or SW phases of the tidal cycle, whereas pituitary prl gene expression and plasma PRL levels remained stable. Branchial patterns of ncc2, nkcc1a, nkaα1a, nkaα1b, cftr, and aqp3 gene expression indicated that fish exposed to tidally changing salinities regulate the expression of these gene transcripts in a similar fashion as fish held under static SW conditions. By contrast, branchial prlr1 and prlr2 levels were highly labile throughout the tidal cycle. We conclude that local (branchial) regulation of endocrine signaling underlies the capacity of euryhaline fishes, such as Mozambique tilapia, to thrive under dynamic salinity conditions.
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Affiliation(s)
- Andre P Seale
- Department of Human Nutrition, Food, and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA.
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kaneohe, HI, 96744, USA.
| | - K Keano Pavlosky
- Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA
| | - Fritzie T Celino-Brady
- Department of Human Nutrition, Food, and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA
| | - Yoko Yamaguchi
- Institute of Agricultural and Life Sciences, Academic Assembly, Shimane University, Matsue, Shimane, 690-8504, Japan
| | - Jason P Breves
- Department of Biology, Skidmore College, Saratoga Springs, NY, 12866, USA
| | - Darren T Lerner
- University of Hawai'i Sea Grant College Program, University of Hawai'i at Mānoa, Honolulu, HI, 96822, USA
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19
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Pavlosky KK, Yamaguchi Y, Lerner DT, Seale AP. The effects of transfer from steady-state to tidally-changing salinities on plasma and branchial osmoregulatory variables in adult Mozambique tilapia. Comp Biochem Physiol A Mol Integr Physiol 2018; 227:134-145. [PMID: 30315867 DOI: 10.1016/j.cbpa.2018.10.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 10/03/2018] [Indexed: 12/16/2022]
Abstract
The Mozambique tilapia, Oreochromis mossambicus, is a teleost fish native to estuarine waters that vary in salinity between fresh water (FW) and seawater (SW). The neuroendocrine system plays a key role in salinity acclimation by directing ion uptake and extrusion in osmoregulatory tissues such as gill. While most studies with O. mossambicus have focused on acclimation to steady-state salinities, less is known about the ability of adult fish to acclimate to dynamically-changing salinities. Plasma osmolality, prolactin (PRL) levels, and branchial gene expression of PRL receptors (PRLR1 and PRLR2), Na+/Cl- and Na+/K+/2Cl- co-transporters (NCC and NKCC), Na+/K+-ATPase (NKAα1a and NKAα1b), cystic fibrosis transmembrane conductance regulator (CFTR), and aquaporin 3 (AQP3) were measured in fish reared in FW and SW steady-state salinities, in a tidal regimen (TR) where salinities changed between FW and SW every six hours, and in fish transferred from FW or SW to TR. Regardless of rearing regimen, plasma osmolality was higher in fish in SW than in FW fish, while plasma PRL was lower in fish in SW. Furthermore, branchial gene expression of effectors of ion transport in TR fish showed greater similarity to those in steady-state SW fish than in FW fish. By seven days of transfer from steady-state FW or SW to TR, plasma osmolality, plasma PRL and branchial expression of effectors of ion transport were similar to those of fish reared in TR since larval stages. These findings demonstrate the ability of adult tilapia reared in steady-state salinities to successfully acclimate to dynamically-changing salinities. Moreover, the present findings suggest that early exposure to salinity changes does not significantly improve survivability in future challenge with dynamically-changing salinities.
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Affiliation(s)
- K Keano Pavlosky
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI 96744, USA; Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA
| | - Yoko Yamaguchi
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI 96744, USA; Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane 690-8504, Japan
| | - Darren T Lerner
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI 96744, USA; University of Hawai'i Sea Grant College Program, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA
| | - Andre P Seale
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kāne'ohe, HI 96744, USA; Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
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20
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Yamaguchi Y, Breves JP, Haws MC, Lerner DT, Grau EG, Seale AP. Acute salinity tolerance and the control of two prolactins and their receptors in the Nile tilapia (Oreochromis niloticus) and Mozambique tilapia (O. mossambicus): A comparative study. Gen Comp Endocrinol 2018; 257:168-176. [PMID: 28652133 PMCID: PMC5742082 DOI: 10.1016/j.ygcen.2017.06.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 05/16/2017] [Accepted: 06/21/2017] [Indexed: 12/15/2022]
Abstract
Osmoregulation in vertebrates is largely controlled by the neuroendocrine system. Prolactin (PRL) is critical for the survival of euryhaline teleosts in fresh water by promoting ion retention. In the euryhaline Mozambique tilapia (Oreochromis mossambicus), pituitary PRL cells release two PRL isoforms, PRL188 and PRL177, in response to a fall in extracellular osmolality. Both PRLs function via two PRL receptors (PRLRs) denoted PRLR1 and PRLR2. We conducted a comparative study using the Nile tilapia (O. niloticus), a close relative of Mozambique tilapia that is less tolerant to increases in environmental salinity, to investigate the regulation of PRLs and PRLRs upon acute hyperosmotic challenges in vivo and in vitro. We hypothesized that differences in the regulation of PRLs and PRLRs underlie the variation in salinity tolerance of tilapias within the genus Oreochromis. When transferred from fresh water to brackish water (20‰), Nile tilapia increased plasma osmolality and decreased circulating PRLs, especially PRL177, to a greater extent than Mozambique tilapia. In dispersed PRL cell incubations, the release of both PRLs was less sensitive to variations in medium osmolality in Nile tilapia than in Mozambique tilapia. By contrast, increases in pituitary and branchial prlr2 gene expression in response to a rise in extracellular osmolality were more pronounced in Nile tilapia relative to its congener, both in vitro and in vivo. Together, these results support the conclusion that inter-specific differences in salinity tolerance between the two tilapia congeners are tied, at least in part, to the distinct responses of both PRLs and their receptors to osmotic stimuli.
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Affiliation(s)
- Yoko Yamaguchi
- Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kaneohe, HI 96744, USA; Department of Biological Science, Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane 690-8504, Japan
| | - Jason P Breves
- Department of Biology, Skidmore College, Saratoga Springs, NY 12866, USA
| | - Maria C Haws
- Pacific Aquaculture and Coastal Resources Center, University of Hawai'i at Hilo, Hilo, HI 96720, USA
| | - Darren T Lerner
- Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kaneohe, HI 96744, USA; Sea Grant College Program, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA
| | - E Gordon Grau
- Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kaneohe, HI 96744, USA
| | - Andre P Seale
- Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kaneohe, HI 96744, USA; Department of Human Nutrition, Food and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, HI 96822, USA.
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21
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González-Mira A, Torreblanca A, Hontoria F, Navarro JC, Mañanós E, Varó I. Effects of ibuprofen and carbamazepine on the ion transport system and fatty acid metabolism of temperature conditioned juveniles of Solea senegalensis. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 148:693-701. [PMID: 29172150 DOI: 10.1016/j.ecoenv.2017.11.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 11/02/2017] [Accepted: 11/09/2017] [Indexed: 06/07/2023]
Abstract
The increasing presence of pharmaceuticals in aquatic environments in the last decades, derived from human and veterinary use, has become an important environmental problem. Previous studies have shown that ibuprofen (IB) and carbamazepine (CBZ) modify physiological and biochemical processes in Senegalese sole (Solea senegalensis) in a temperature-dependent manner. In other vertebrates, there is evidence that both of these pharmaceuticals interfere with the 'arachidonic acid (AA) cascade', which is responsible for the biosynthesis of numerous enzymes that are involved in the osmoregulatory process. The present work aims to study the temperature-dependent effects of these two pharmaceuticals on several biochemical and molecular parameters in Senegalese sole. Regarding osmoregulation, Na+, K+ -ATPase enzyme activity was determined in the gills, kidney and intestine, and the expressions of both Na+, K+ -ATPase 1α-subunit isoforms (ATP1A1a and ATP1A1b) were quantified in gills. Gill prostaglandin-endoperoxide synthase-2 (PTGS2) gene expression and fatty acid composition were selected to determine the interference of both pharmaceuticals with the AA cascade. Senegalese sole juveniles, acclimatised at 15°C or 20°C, were exposed through intraperitoneal injection to IB (10mg/kg) and CBZ (1mg/kg) for 48h. Non-injected fish (Control) and those injected with the carrier (sunflower oil; S.O.), acclimated at each of the two temperatures, were used for comparison. The results show that IB directly affected the osmoregulatory mechanisms that alter gill and intestine Na+, K+ -ATPase activities. In addition, the copy number of ATP1A1a was higher at 20°C than at 15°C, which could be a direct response to the temperature variation. The gene expression of PTGS2 was affected by neither drug administration nor acclimation temperature. Nevertheless, detailed analysis of AA and eicosapentaenoic acid (EPA) percentages revealed a CBZ-derived effect in the fatty acid composition of the gills.
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Affiliation(s)
- A González-Mira
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universitat de València, Dr. Moliner 50, Burjassot, 46100 Valencia, Spain
| | - A Torreblanca
- Departamento de Biología Celular, Biología Funcional y Antropología Física, Universitat de València, Dr. Moliner 50, Burjassot, 46100 Valencia, Spain.
| | - F Hontoria
- Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, 12595 Castellón, Spain
| | - J C Navarro
- Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, 12595 Castellón, Spain
| | - E Mañanós
- Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, 12595 Castellón, Spain
| | - I Varó
- Instituto de Acuicultura Torre de la Sal (IATS-CSIC), Ribera de Cabanes, 12595 Castellón, Spain
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22
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Breves JP, Keith PLK, Hunt BL, Pavlosky KK, Inokuchi M, Yamaguchi Y, Lerner DT, Seale AP, Grau EG. clc-2c is regulated by salinity, prolactin and extracellular osmolality in tilapia gill. J Mol Endocrinol 2017; 59:391-402. [PMID: 28974537 PMCID: PMC5660657 DOI: 10.1530/jme-17-0144] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/03/2017] [Indexed: 12/11/2022]
Abstract
Teleosts inhabiting fresh water (FW) depend upon ion-absorptive ionocytes to counteract diffusive ion losses to the external environment. A Clc Cl- channel family member, Clc-2c, was identified as a conduit for basolateral Cl- transport by Na+/Cl- cotransporter 2 (Ncc2)-expressing ionocytes in stenohaline zebrafish (Danio rerio). It is unresolved whether Clc-2c/clc-2c is expressed in euryhaline species and how extrinsic and/or intrinsic factors modulate branchial clc-2c mRNA. Here, we investigated whether environmental salinity, prolactin (Prl) and osmotic conditions modulate clc-2c expression in euryhaline Mozambique tilapia (Oreochromis mossambicus). Branchial clc-2c and ncc2 mRNAs were enhanced in tilapia transferred from seawater (SW) to FW, whereas both mRNAs were attenuated upon transfer from FW to SW. Next, we injected hypophysectomized tilapia with ovine prolactin (oPrl) and observed a marked increase in clc-2c from saline-injected controls. To determine whether Prl regulates clc-2c in a gill-autonomous fashion, we incubated gill filaments in the presence of homologous tilapia Prls (tPrl177 and tPrl188). By 24 h, tPrl188 stimulated clc-2c expression ~5-fold from controls. Finally, filaments incubated in media ranging from 280 to 450 mosmol/kg for 3 and 6 h revealed that extracellular osmolality exerts a local effect on clc-2c expression; clc-2c was diminished by hyperosmotic conditions (450 mosmol/kg) compared with isosmotic controls (330 mosmol/kg). Our collective results suggest that hormonal and osmotic control of branchial clc-2c contributes to the FW adaptability of Mozambique tilapia. Moreover, we identify for the first time a regulatory link between Prl and a Clc Cl- channel in a vertebrate.
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Affiliation(s)
- Jason P Breves
- Department of BiologySkidmore College, Saratoga Springs, New York, USA
| | - Paige L K Keith
- Department of BiologySkidmore College, Saratoga Springs, New York, USA
| | - Bethany L Hunt
- Department of BiologySkidmore College, Saratoga Springs, New York, USA
| | - K Keano Pavlosky
- Hawai'i Institute of Marine BiologyUniversity of Hawai'i, Kaneohe, Hawaii, USA
| | - Mayu Inokuchi
- Department of Life SciencesToyo University, Itakura, Gunma, Japan
| | - Yoko Yamaguchi
- Department of Biological ScienceShimane University, Matsue, Shimane, Japan
| | - Darren T Lerner
- Hawai'i Institute of Marine BiologyUniversity of Hawai'i, Kaneohe, Hawaii, USA
- Sea Grant College ProgramUniversity of Hawai'i at Mānoa, Honolulu, Hawaii, USA
| | - Andre P Seale
- Hawai'i Institute of Marine BiologyUniversity of Hawai'i, Kaneohe, Hawaii, USA
- Department of Human NutritionFood and Animal Sciences, University of Hawai'i at Mānoa, Honolulu, Hawaii, USA
| | - E Gordon Grau
- Hawai'i Institute of Marine BiologyUniversity of Hawai'i, Kaneohe, Hawaii, USA
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23
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Bossus MC, Bollinger RJ, Reed PJ, Tipsmark CK. Prolactin and cortisol regulate branchial claudin expression in Japanese medaka. Gen Comp Endocrinol 2017; 240:77-83. [PMID: 27663882 DOI: 10.1016/j.ygcen.2016.09.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 09/14/2016] [Accepted: 09/19/2016] [Indexed: 12/28/2022]
Abstract
Several gill claudin (Cldn) tight junction proteins in Japanese medaka are regulated by salinity (cldn10 paralogs and cldn28b), while others are constitutively expressed (cldn27a, cldn28a and cldn30c). The role of the endocrine system in this regulation has yet to be understood. The in vitro effects of cortisol and prolactin on cldn expression in gill explant cultures were investigated in medaka. ncc2b and cftr were used as markers of specific ionocytes associated with freshwater- and seawater-acclimation, respectively. Concentration-response experiments were performed by overnight incubation with 0, 0.1, 1 and 10μgmL-1 cortisol or 0, 0.01, 0.1 and 1μgmL-1 ovine prolactin. Cortisol significantly up-regulated cftr, ncc2b, cldn10 paralogs, cldn27a and cldn30c from 1.2- to 5-fold control levels at 10μgmL-1. Cortisol had no effect on cldn28a and cldn28b. Prolactin had a concentration-dependent effect, decreasing expression of cftr (1μgmL-1, 2.2-fold) while increasing ncc2b (from 0.1μgmL-1, 6-7-fold). Prolactin up-regulated expression of 3 cldns: cldn28b (0.1 and 1μgmL-1), cldn10c and cldn10f (1μgmL-1), with up to 2-, 2.5- and 2-fold of control level, respectively. A combination experiment with both hormones showed that they act in synergy on cldn28b and have an additive effect on cftr, ncc2b, cldn10c and cldn10f. Our results showed that cortisol and prolactin are essential to maintain the expression of specific branchial claudins. This work also provides evidence that both hormones act directly on gill of medaka to modulate determinants of paracellular ion movement.
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Affiliation(s)
- Maryline C Bossus
- Department of Biological Sciences, University of Arkansas, SCEN 601, Fayetteville, AR 72701, USA; Lyon College, Derby Center for Science and Mathematics, 2300 Highland Road, Batesville, AR 72501, USA
| | - Rebecca J Bollinger
- Department of Biological Sciences, University of Arkansas, SCEN 601, Fayetteville, AR 72701, USA
| | - P Justin Reed
- Department of Biological Sciences, University of Arkansas, SCEN 601, Fayetteville, AR 72701, USA
| | - Christian K Tipsmark
- Department of Biological Sciences, University of Arkansas, SCEN 601, Fayetteville, AR 72701, USA.
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24
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Yamaguchi Y, Moriyama S, Lerner DT, Grau EG, Seale AP. Autocrine Positive Feedback Regulation of Prolactin Release From Tilapia Prolactin Cells and Its Modulation by Extracellular Osmolality. Endocrinology 2016; 157:3505-16. [PMID: 27379370 PMCID: PMC6285229 DOI: 10.1210/en.2015-1969] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 06/27/2016] [Indexed: 12/24/2022]
Abstract
Prolactin (PRL) is a vertebrate hormone with diverse actions in osmoregulation, metabolism, reproduction, and in growth and development. Osmoregulation is fundamental to maintaining the functional structure of the macromolecules that conduct the business of life. In teleost fish, PRL plays a critical role in osmoregulation in fresh water. Appropriately, PRL cells of the tilapia are directly osmosensitive, with PRL secretion increasing as extracellular osmolality falls. Using a model system that employs dispersed PRL cells from the euryhaline teleost fish, Oreochromis mossambicus, we investigated the autocrine regulation of PRL cell function. Unknown was whether these PRL cells might also be sensitive to autocrine feedback and whether possible autocrine regulation might interact with the well-established regulation by physiologically relevant changes in extracellular osmolality. In the cell-perfusion system, ovine PRL and two isoforms of tilapia PRL (tPRL), tPRL177 and tPRL188, stimulated the release of tPRLs from the dispersed PRL cells. These effects were significant within 5-10 minutes and lasted the entire course of exposure, ceasing within 5-10 minutes of removal of tested PRLs from the perifusion medium. The magnitude of response varied between tPRL177 and tPRL188 and was modulated by extracellular osmolality. On the other hand, the gene expression of tPRLs was mainly unchanged or suppressed by static incubations of PRL cells with added PRLs. By demonstrating the regulatory complexity driven by positive autocrine feedback and its interaction with osmotic stimuli, these findings expand upon the knowledge that pituitary PRL cells are regulated complexly through multiple factors and interactions.
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Affiliation(s)
- Yoko Yamaguchi
- Hawai'i Institute of Marine Biology (Y.Y., D.T.L., E.G.G., A.P.S.), University of Hawai'i at Mānoa, Kāne'ohe, Hawai'i 96744; School of Marine Biosciences (S.M.), Kitasato University, Minami-ku, Sagamihara, Kanagawa 252-0373, Japan; and University of Hawai'i Sea Grant College Program (D.T.L.) and Department of Human Nutrition, Food and Animal Sciences (A.P.S.), University of Hawai'i at Mānoa, Honolulu, Hawai'i 96822
| | - Shunsuke Moriyama
- Hawai'i Institute of Marine Biology (Y.Y., D.T.L., E.G.G., A.P.S.), University of Hawai'i at Mānoa, Kāne'ohe, Hawai'i 96744; School of Marine Biosciences (S.M.), Kitasato University, Minami-ku, Sagamihara, Kanagawa 252-0373, Japan; and University of Hawai'i Sea Grant College Program (D.T.L.) and Department of Human Nutrition, Food and Animal Sciences (A.P.S.), University of Hawai'i at Mānoa, Honolulu, Hawai'i 96822
| | - Darren T Lerner
- Hawai'i Institute of Marine Biology (Y.Y., D.T.L., E.G.G., A.P.S.), University of Hawai'i at Mānoa, Kāne'ohe, Hawai'i 96744; School of Marine Biosciences (S.M.), Kitasato University, Minami-ku, Sagamihara, Kanagawa 252-0373, Japan; and University of Hawai'i Sea Grant College Program (D.T.L.) and Department of Human Nutrition, Food and Animal Sciences (A.P.S.), University of Hawai'i at Mānoa, Honolulu, Hawai'i 96822
| | - E Gordon Grau
- Hawai'i Institute of Marine Biology (Y.Y., D.T.L., E.G.G., A.P.S.), University of Hawai'i at Mānoa, Kāne'ohe, Hawai'i 96744; School of Marine Biosciences (S.M.), Kitasato University, Minami-ku, Sagamihara, Kanagawa 252-0373, Japan; and University of Hawai'i Sea Grant College Program (D.T.L.) and Department of Human Nutrition, Food and Animal Sciences (A.P.S.), University of Hawai'i at Mānoa, Honolulu, Hawai'i 96822
| | - Andre P Seale
- Hawai'i Institute of Marine Biology (Y.Y., D.T.L., E.G.G., A.P.S.), University of Hawai'i at Mānoa, Kāne'ohe, Hawai'i 96744; School of Marine Biosciences (S.M.), Kitasato University, Minami-ku, Sagamihara, Kanagawa 252-0373, Japan; and University of Hawai'i Sea Grant College Program (D.T.L.) and Department of Human Nutrition, Food and Animal Sciences (A.P.S.), University of Hawai'i at Mānoa, Honolulu, Hawai'i 96822
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