1
|
Sato T, Goto-Inoue N, Kimishima M, Toyoharu J, Minei R, Ogura A, Nagoya H, Mori T. A novel ND1 mitochondrial DNA mutation is maternally inherited in growth hormone transgenesis in amago salmon (Oncorhynchus masou ishikawae). Sci Rep 2022; 12:6720. [PMID: 35469048 PMCID: PMC9038734 DOI: 10.1038/s41598-022-10521-4] [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: 08/25/2021] [Accepted: 03/22/2022] [Indexed: 11/12/2022] Open
Abstract
Growth hormone (GH) transgenesis can be used to manipulate the growth performance of fish and mammals. In this study, homozygous and hemizygous GH-transgenic amago salmon (Oncorhynchus masou ishikawae) derived from a single female exhibited hypoglycemia. Proteomic and signal network analyses using iTRAQ indicated a decreased NAD+/NADH ratio in transgenic fish, indicative of reduced mitochondrial ND1 function and ROS levels. Mitochondrial DNA sequencing revealed that approximately 28% of the deletion mutations in the GH homozygous- and hemizygous-female-derived mitochondrial DNA occurred in ND1. These fish also displayed decreased ROS levels. Our results indicate that GH transgenesis in amago salmon may induce specific deletion mutations that are maternally inherited over generations and alter energy production.
Collapse
Affiliation(s)
- Tomohiko Sato
- Department of Marine Science and Resources, Nihon University College of Bioresource Sciences, Kameino 1866, Fujisawa, 252-0880, Japan
| | - Naoko Goto-Inoue
- Department of Marine Science and Resources, Nihon University College of Bioresource Sciences, Kameino 1866, Fujisawa, 252-0880, Japan
| | - Masaya Kimishima
- Department of Marine Science and Resources, Nihon University College of Bioresource Sciences, Kameino 1866, Fujisawa, 252-0880, Japan
| | - Jike Toyoharu
- Research Institute of Medical Research Support Center Electron Microscope Laboratory, School of Medicine, Nihon University, Tokyo, 173-8610, Japan
| | - Ryuhei Minei
- Department of Computer Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, 526-0829, Japan
| | - Atsushi Ogura
- Department of Computer Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, 526-0829, Japan
| | - Hiroyuki Nagoya
- National Research Institute of Aquaculture, Fisheries Research and Education Agency, Minamiise, 516-0193, Japan
| | - Tsukasa Mori
- Department of Marine Science and Resources, Nihon University College of Bioresource Sciences, Kameino 1866, Fujisawa, 252-0880, Japan.
| |
Collapse
|
2
|
Fujimoto T, Nishimura T. Chromosome Set Manipulation and Genome Manipulation in Aquaculture. J JPN SOC FOOD SCI 2021. [DOI: 10.3136/nskkk.68.277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
3
|
Chan MTT, Muttray A, Sakhrani D, Woodward K, Kim JH, Christensen KA, Koop BF, Devlin RH. Sexually Dimorphic Growth Stimulation in a Strain of Growth Hormone Transgenic Coho Salmon (Oncorhynchus kisutch). MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2021; 23:140-148. [PMID: 33481139 PMCID: PMC7929968 DOI: 10.1007/s10126-020-10012-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 11/29/2020] [Indexed: 06/12/2023]
Abstract
Growth hormone (GH) transgenic fish often exhibit remarkable transformations in growth rate and other phenotypes relative to wild-type. The 5750A transgenic coho salmon strain exhibits strong sexually dimorphic growth, with females possessing growth stimulation at a level typical of that seen for both sexes in other strains harbouring the same gene construct (e.g. M77), while males display a modest level of growth stimulation. GH mRNA levels were significantly higher in females than in males of the 5750A strain but equivalent in the M77 strain, indicating sex and transgene insertion locus altered transgene expression. We found that acute estradiol treatments did not influence GH expression in either strain (5750A and M77) or the transgene promoter (metallothionein-B), suggesting that estradiol level was not a significant factor influencing transgene activity. The feminization of XX and XY fish of the 5750A and M77 strains generated all-female groups and resulted in equalized growth of the two genetic sexes, suggesting that the presence of the Y chromosome was not directly capable of influencing the GH transgene-mediated growth in a physiological female conditions. These data suggest that the difference in growth rate seen between the sexes in the 5750A strain arises from non-estradiol-mediated sex influences on gene regulation at the transgene locus. This study shows how genetic factors and transgene insertion sites can influence transgene expression with significant consequent effects on phenotype.
Collapse
Affiliation(s)
- Michelle T T Chan
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, V7V 1N6, Canada.
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada.
| | - Annette Muttray
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, V7V 1N6, Canada
- New York Institute of Technology, #1700-701 West Georgia Street, Vancouver, BC, V7Y 1K8, Canada
| | - Dionne Sakhrani
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, V7V 1N6, Canada
| | - Krista Woodward
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, V7V 1N6, Canada
| | - Jin-Hyoung Kim
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, V7V 1N6, Canada
- Division of Life Sciences, Korea Polar Research Institute, 26 Sondomirae-ro, Yeonsu-gu, Incheon, 21990, South Korea
| | - Kris A Christensen
- Department of Biology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Ben F Koop
- Department of Biology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Robert H Devlin
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, V7V 1N6, Canada
| |
Collapse
|
4
|
Jazi V, Farahi M, Khajali F, Abousaad S, Ferket P, Assadi Soumeh E. Effect of dietary supplementation of whey powder and Bacillus subtilis on growth performance, gut and hepatic function, and muscle antioxidant capacity of Japanese quail. J Anim Physiol Anim Nutr (Berl) 2020; 104:886-897. [PMID: 32072684 DOI: 10.1111/jpn.13323] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 11/04/2019] [Accepted: 11/15/2019] [Indexed: 12/25/2022]
Abstract
This experiment was conducted to evaluate the effects of dietary supplementation of whey powder (WP), Bacillus subtilis (BAS), and their combination (MIX) on growth performance, intestinal morphology, caecal microflora, hepatic gene expression, blood metabolites, and skeletal muscle antioxidant capacity in Japanese quails. A total of 400 one-day-old Japanese quails were randomly distributed to 20-floor pens (4 dietary treatments, 5 replications per treatment, 20 birds per pen). The birds were fed a basal diet (control, CON) or the basal diet supplemented with 40 g/kg WP, 1 g/kg BAS probiotic or 40 g/kg WP plus 1 g/kg BAS probiotic for five weeks. Feed intake was not affected by the treatments at any stage of the trial. However, the WP, BAS, and MIX feed had better weight gain and feed conversion ratio compared to the CON during the entire production period (day 1-35; p < .05). Feeding the WP, BAS, and MIX diets caused no significant difference in morphometric measures in the duodenum, jejunum, and ileum other than the villus height to crypt depth ratio in the ileum (p < .05). The expression of insulin-like growth factor-1 (IGF-1) and growth hormone genes was highly upregulated in the liver of the birds fed the MIX diet (p < .05). Feeding birds with the diets containing WP, BAS, and MIX increased the population of caecal lactic acid bacteria and reduced serum cholesterol concentration compared to the CON diet (p < .05). Likewise, the tested feed additives increased superoxide dismutase and glutathione peroxidase enzyme activities in the thigh muscle (p < .05). No synergistic effect was found between WP and BAS in studied parameters other than IGF-1 gene expression. Improved growth performance of Japanese quails by feeding the WP, BAS, and the MIX feed could be linked to improved absorptive capacity of the small intestine as well as over-expression of anabolic growth factors. In conclusion, WP with or without BAS could be considered as a beneficial dietary supplement to enhance productive performance, gut functionality, and antioxidant capacity of Japanese quail.
Collapse
Affiliation(s)
- Vahid Jazi
- Department of Animal and Poultry Nutrition, Faculty of Animal Science, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
| | - Majid Farahi
- Genetics and Animal Breeding, Department of Animal Science, Tarbiat Modares University, Tehran, Iran
| | - Fariborz Khajali
- Department of Animal Science, Shahrekord University, Shahrekord, Iran
| | - Shaymma Abousaad
- Prestage Department of Poultry Science, NC State University, Raleigh, NC, USA
| | - Peter Ferket
- Prestage Department of Poultry Science, NC State University, Raleigh, NC, USA
| | - Elham Assadi Soumeh
- School of Agriculture and Food Science, University of Queensland, Qld, Australia
| |
Collapse
|
5
|
Novales Flamarique I, Sayed Ahmed A, Cheng CL, Molday RS, Devlin RH. Growth hormone regulates opsin expression in the retina of a salmonid fish. J Neuroendocrinol 2019; 31:e12804. [PMID: 31630448 DOI: 10.1111/jne.12804] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 09/07/2019] [Accepted: 10/18/2019] [Indexed: 01/18/2023]
Abstract
Colour vision relies on retinal photoreceptors that express a different predominant visual pigment protein (opsin). In several vertebrates, the primary opsin expressed by a photoreceptor can change throughout ontogeny, although the molecular factors that influence such regulation are poorly understood. One of these factors is thyroid hormone which, together with its receptors, modulates opsin expression in the retinas of multiple vertebrates including rodents and salmonid fishes. In the latter, thyroid hormone induces a switch in opsin expression from SWS1 (ultraviolet light sensitive) to SWS2 (short wavelength or blue light sensitive) in the single cone photoreceptors of the retina. The actions of other hormones on opsin expression have not been investigated. In the present study, we used a transgenic strain of coho salmon (Oncorhynchus kitsutch) with enhanced levels of circulating growth hormone compared to that of wild siblings to assess the effects of this hormone on the SWS1 to SWS2 opsin switch. Transgenic fish showed a developmentally accelerated opsin switch compared to size-matched controls as assessed by immunohistological and in situ hybridisation labelling of photoreceptors and by quantification of transcripts using quantitative polymerase chain reaction. This accelerated switch led to a different spectral sensitivity maximum, under a middle to long wavelength adapting background, from ultraviolet (λmax ~ 380 nm) in controls to short wavelengths (λmax ~ 430 nm) in transgenics, demonstrating altered colour vision. The effects of growth hormone over-expression were independent of circulating levels of thyroid hormone (triiodothyronine), the hormone typically associated with opsin switches in vertebrates.
Collapse
Affiliation(s)
- Inigo Novales Flamarique
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Ahmed Sayed Ahmed
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Christiana L Cheng
- Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - Robert S Molday
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | | |
Collapse
|
6
|
Debode F, Janssen E, Marien A, Devlin RH, Lieske K, Mankertz J, Berben G. Detection of Transgenic Atlantic and Coho Salmon by Real-time PCR. FOOD ANAL METHOD 2018. [DOI: 10.1007/s12161-018-1214-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
7
|
Trukhachev V, Skripkin V, Kvochko A, Kulichenko A, Kovalev D, Pisarenko S, Volynkina A, Selionova M, Aybazov M, Krivoruchko A. Correlation between gene expression profiles in muscle and live weight in Dzhalginsky Merino sheep. REV COLOMB CIENC PEC 2016. [DOI: 10.17533/udea.rccp.v29n3a04] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
|
8
|
White SL, Volkoff H, Devlin RH. Regulation of feeding behavior and food intake by appetite-regulating peptides in wild-type and growth hormone-transgenic coho salmon. Horm Behav 2016; 84:18-28. [PMID: 27149948 DOI: 10.1016/j.yhbeh.2016.04.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 04/01/2016] [Accepted: 04/16/2016] [Indexed: 12/17/2022]
Abstract
Survival, competition, growth and reproductive success in fishes are highly dependent on food intake, food availability and feeding behavior and are all influenced by a complex set of metabolic and neuroendocrine mechanisms. Overexpression of growth hormone (GH) in transgenic fish can result in greatly enhanced growth rates, feed conversion, feeding motivation and food intake. The objectives of this study were to compare seasonal feeding behavior of non-transgenic wild-type (NT) and GH-transgenic (T) coho salmon (Oncorhynchus kisutch), and to examine the effects of intraperitoneal injections of the appetite-regulating peptides cholecystokinin (CCK-8), bombesin (BBS), glucagon-like peptide-1 (GLP-1), and alpha-melanocyte-stimulating hormone (α-MSH) on feeding behavior. T salmon fed consistently across all seasons, whereas NT dramatically reduced their food intake in winter, indicating the seasonal regulation of appetite can be altered by overexpression of GH in T fish. Intraperitoneal injections of CCK-8 and BBS caused a significant and rapid decrease in food intake for both genotypes. Treatment with either GLP-1 or α-MSH resulted in a significant suppression of food intake for NT but had no effect in T coho salmon. The differential response of T and NT fish to α-MSH is consistent with the melanocortin-4 receptor system being a significant pathway by which GH acts to stimulate appetite. Taken together, these results suggest that chronically increased levels of GH alter feeding regulatory pathways to different extents for individual peptides, and that altered feeding behavior in transgenic coho salmon may arise, in part, from changes in sensitivity to peripheral appetite-regulating signals.
Collapse
Affiliation(s)
- Samantha L White
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada.
| | - Helene Volkoff
- Departments of Biology and Biochemistry, Memorial University of Newfoundland, St John's, NL A1B 3X9, Canada.
| | - Robert H Devlin
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7V 1N6, Canada.
| |
Collapse
|
9
|
Kim JH, Leggatt RA, Chan M, Volkoff H, Devlin RH. Effects of chronic growth hormone overexpression on appetite-regulating brain gene expression in coho salmon. Mol Cell Endocrinol 2015; 413:178-88. [PMID: 26123591 DOI: 10.1016/j.mce.2015.06.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 06/22/2015] [Indexed: 10/23/2022]
Abstract
Organisms must carefully regulate energy intake and expenditure to balance growth and trade-offs with other physiological processes. This regulation is influenced by key pathways controlling appetite, feeding behaviour and energy homeostasis. Growth hormone (GH) transgenesis provides a model where food intake can be elevated, and is associated with dramatic modifications of growth, metabolism, and feeding behaviour, particularly in fish. RNA-Seq and qPCR analyses were used to compare the expression of multiple genes important in appetite regulation within brain regions and the pituitary gland (PIT) of GH transgenic (fed fully to satiation or restricted to a wild-type ration throughout their lifetime) and wild-type coho salmon (Oncorhynchus kisutch). RNA-Seq results showed that differences in both genotype and ration levels resulted in differentially expressed genes associated with appetite regulation in transgenic fish, including elevated Agrp1 in hypothalamus (HYP) and reduced Mch in PIT. Altered mRNA levels for Agrp1, Npy, Gh, Ghr, Igf1, Mch and Pomc were also assessed using qPCR analysis. Levels of mRNA for Agrp1, Gh, and Ghr were higher in transgenic than wild-type fish in HYP and in the preoptic area (POA), with Agrp1 more than 7-fold higher in POA and 12-fold higher in HYP of transgenic salmon compared to wild-type fish. These data are consistent with the known roles of orexigenic factors on foraging behaviour acting via GH and through MC4R receptor-mediated signalling. Igf1 mRNA was elevated in fully-fed transgenic fish in HYP and POA, but not in ration-restricted fish, yet both of these types of transgenic animals have very pronounced feeding behaviour relative to wild-type fish, suggesting IGF1 is not playing a direct role in appetite stimulation acting via paracrine or autocrine mechanisms. The present findings provide new insights on mechanisms ruling altered appetite regulation in response to chronically elevated GH, and on potential pathways by which elevated feeding response is controlled, independently of food availability and growth.
Collapse
Affiliation(s)
- Jin-Hyoung Kim
- Fisheries and Oceans Canada, Centre for Aquaculture and Environmental Research, 4160 Marine Drive, West Vancouver, BC V7V 1N6 Canada
| | - Rosalind A Leggatt
- Fisheries and Oceans Canada, Centre for Aquaculture and Environmental Research, 4160 Marine Drive, West Vancouver, BC V7V 1N6 Canada
| | - Michelle Chan
- Fisheries and Oceans Canada, Centre for Aquaculture and Environmental Research, 4160 Marine Drive, West Vancouver, BC V7V 1N6 Canada
| | - Hélène Volkoff
- Department of Biology, Memorial University of Newfoundland, St. John's, NL A1B 3X9 Canada; Department of Biochemistry, Memorial University of Newfoundland, St. John's, NL A1B 3X9 Canada
| | - Robert H Devlin
- Fisheries and Oceans Canada, Centre for Aquaculture and Environmental Research, 4160 Marine Drive, West Vancouver, BC V7V 1N6 Canada.
| |
Collapse
|
10
|
Garcia de la Serrana D, Devlin RH, Johnston IA. RNAseq analysis of fast skeletal muscle in restriction-fed transgenic coho salmon (Oncorhynchus kisutch): an experimental model uncoupling the growth hormone and nutritional signals regulating growth. BMC Genomics 2015; 16:564. [PMID: 26228074 PMCID: PMC4521378 DOI: 10.1186/s12864-015-1782-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 07/15/2015] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Coho salmon (Oncorhynchus kisutch) transgenic for growth hormone (Gh) express Gh in multiple tissues which results in increased appetite and continuous high growth with satiation feeding. Restricting Gh-transgenics to the same lower ration (TR) as wild-type fish (WT) results in similar growth, but with the recruitment of fewer, larger diameter, muscle skeletal fibres to reach a given body size. In order to better understand the genetic mechanisms behind these different patterns of muscle growth and to investigate how the decoupling of Gh and nutritional signals affects gene regulation we used RNA-seq to compare the fast skeletal muscle transcriptome in TR and WT coho salmon. RESULTS Illumina sequencing of individually barcoded libraries from 6 WT and 6 TR coho salmon yielded 704,550,985 paired end reads which were used to construct 323,115 contigs containing 19,093 unique genes of which >10,000 contained >90 % of the coding sequence. Transcripts coding for 31 genes required for myoblast fusion were identified with 22 significantly downregulated in TR relative to WT fish, including 10 (vaspa, cdh15, graf1, crk, crkl, dock1, trio, plekho1a, cdc42a and dock5) associated with signaling through the cell surface protein cadherin. Nineteen out of 44 (43 %) translation initiation factors and 14 of 47 (30 %) protein chaperones were upregulated in TR relative to WT fish. CONCLUSIONS TR coho salmon showed increased growth hormone transcripts and gene expression associated with protein synthesis and folding than WT fish even though net rates of protein accretion were similar. The uncoupling of Gh and amino acid signals likely results in additional costs of transcription associated with protein turnover in TR fish. The predicted reduction in the ionic costs of homeostasis in TR fish associated with increased fibre size were shown to involve multiple pathways regulating myotube fusion, particularly cadherin signaling.
Collapse
Affiliation(s)
| | - Robert H Devlin
- Department of Fisheries and Oceans, Centre for Aquaculture and Environmental Research, 4160 Marine Drive, West Vancouver, BC, V7V 1N6, Canada.
| | - Ian A Johnston
- Scottish Oceans Institute, School of Biology, University of St Andrews, KY16 8LB, St Andrews, Scotland, UK.
| |
Collapse
|
11
|
Cloning and Characterization of Pangasianodon hypophthalmus Growth Hormone Gene and its Heterologous Expression. Appl Biochem Biotechnol 2014; 173:1446-68. [DOI: 10.1007/s12010-014-0946-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 04/23/2014] [Indexed: 10/25/2022]
|
12
|
Devlin RH, Sakhrani D, Biagi CA, Smith JL, Fujimoto T, Beckman B. Growth and endocrine effect of growth hormone transgene dosage in diploid and triploid coho salmon. Gen Comp Endocrinol 2014; 196:112-22. [PMID: 24321178 DOI: 10.1016/j.ygcen.2013.11.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Revised: 11/19/2013] [Accepted: 11/26/2013] [Indexed: 12/14/2022]
Abstract
Growth-hormone transgene dosage, polyploidy, and parental effects on growth and endocrine responses have been assessed in coho salmon. Diploid fry with one or two transgene doses grew equally, whereas later-stage juvenile homozygotes grew faster than hemizygotes. In contrast, homozygotes and hemizygotes grew equally after smoltification, both in sea water and fresh water. Triploid transgenic salmon showed impaired growth which could not be fully overcome with additional transgene copies. Levels of muscle GH mRNA were elevated in two vs. one transgene dose diploids, but in triploids, a dosage effect was observed in muscle but not for animals carrying three transgene doses. IGF-I mRNA levels were elevated in transgenic vs. non-transgenic animals, but a dosage effect was not observed. Diploids and triploids with two transgenes had higher plasma GH levels than one-dose animals, but three-dose triploids showed no further elevation. Circulating IGF-I levels also showed a dosage effect in diploids, but not among any transgene doses in triploids. The present study reveals complex interactions among transgene dosage, maternal effects, developmental stage, and ploidy on growth and endocrine parameters in GH transgenic coho salmon. Specifically, GH transgenes do not always express nor have effects on growth that are directly correlated with the number of transgenes. Further, the reduced growth rate seen in triploid transgenic animals could not be fully overcome by increasing transgene dosage. The findings have relevance for understanding growth physiology, transgene function, and for environmental risk assessments that require understanding phenotypes of hemizygous vs. homozygous transgenic animals in populations.
Collapse
Affiliation(s)
- Robert H Devlin
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7K 1N6, Canada.
| | - Dionne Sakhrani
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7K 1N6, Canada
| | - Carlo A Biagi
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7K 1N6, Canada
| | - Jack L Smith
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC V7K 1N6, Canada
| | - Takafumi Fujimoto
- Faculty and Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato, Hakodate, Hokkaido 041-8611, Japan
| | - Brian Beckman
- Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA 98112, USA
| |
Collapse
|
13
|
Cao M, Chen J, Peng W, Wang Y, Liao L, Li Y, Trudeau VL, Zhu Z, Hu W. Effects of growth hormone over-expression on reproduction in the common carp Cyprinus carpio L. Gen Comp Endocrinol 2014; 195:47-57. [PMID: 24184869 DOI: 10.1016/j.ygcen.2013.10.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 10/17/2013] [Accepted: 10/21/2013] [Indexed: 11/28/2022]
Abstract
To study the complex interaction between growth and reproduction we have established lines of transgenic common carp (Cyprinus carpio) carrying a grass carp (Ctenopharyngodon idellus) growth hormone (GH) transgene. The GH-transgenic fish showed delayed gonadal development compared with non-transgenic common carp. To gain a better understanding of the phenomenon, we studied body growth, gonad development, changes of reproduction related genes and hormones of GH-transgenic common carp for 2years. Over-expression of GH elevated peripheral gh transcription, serum GH levels, and inhibited endogenous GH expression in the pituitary. Hormone analyses indicated that GH-transgenic common carp had reduced pituitary and serum level of luteinizing hormone (LH). Among the tested genes, pituitary lhβ was inhibited in GH-transgenic fish. Further analyses in vitro showed that GH inhibited lhβ expression. Localization of ghr with LH indicates the possibility of direct regulation of GH on gonadotrophs. We also found that GH-transgenic common carp had reduced pituitary sensitivity to stimulation by co-treatments with a salmon gonadotropin-releasing hormone (GnRH) agonist and a dopamine antagonist. Together these results suggest that the main cause of delayed reproductive development in GH transgenic common carp is reduced LH production and release.
Collapse
Affiliation(s)
- Mengxi Cao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Ji Chen
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Wei Peng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of the Chinese Academy of Sciences, Beijing 100049, China
| | - Yaping Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Lanjie Liao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yongming Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Vance L Trudeau
- Department of Biology, Centre for Advanced Research in Environmental Genomics, University of Ottawa, Ottawa K1N 6N5, Canada
| | - Zuoyan Zhu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Wei Hu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
| |
Collapse
|
14
|
McMenamin SK, Minchin JEN, Gordon TN, Rawls JF, Parichy DM. Dwarfism and increased adiposity in the gh1 mutant zebrafish vizzini. Endocrinology 2013; 154:1476-87. [PMID: 23456361 PMCID: PMC3602633 DOI: 10.1210/en.2012-1734] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Somatic growth and adipogenesis are closely associated with the development of obesity in humans. In this study, we identify a zebrafish mutant, vizzini, that exhibits both a severe defect in somatic growth and increased accumulation of adipose tissue. Positional cloning of vizzini revealed a premature stop codon in gh1. Although the effects of GH are largely through igfs in mammals, we found no decrease in the expression of igf transcripts in gh1 mutants during larval development. As development progressed, however, we found overall growth to be progressively retarded and the attainment of specific developmental stages to occur at abnormally small body sizes relative to wild type. Moreover, both subcutaneous (sc) and visceral adipose tissues underwent precocious development in vizzini mutants, and at maturity, the sizes of different fat deposits were greatly expanded relative to wild type. In vivo confocal imaging of sc adipose tissue (SAT) expansion revealed that vizzini mutants exhibit extreme enlargement of adipocyte lipid droplets without a corresponding increase in lipid droplet number. These findings suggest that GH1 signaling restricts SAT hypertrophy in zebrafish. Finally, nutrient deprivation of vizzini mutants revealed that SAT mobilization was greatly diminished during caloric restriction, further implicating GH1 signaling in adipose tissue homeostasis. Overall, the zebrafish gh1 mutant, vizzini, exhibits decreased somatic growth, increased adipose tissue accumulation, and disrupted adipose plasticity after nutrient deprivation and represents a novel model to investigate the in vivo dynamics of vertebrate obesity.
Collapse
Affiliation(s)
- Sarah K McMenamin
- Department of Biology, University of Washington, Box 351800, Seattle, Washington 98195-1800, USA
| | | | | | | | | |
Collapse
|
15
|
Sugiyama M, Takenaga F, Kitani Y, Yamamoto G, Okamoto H, Masaoka T, Araki K, Nagoya H, Mori T. Homozygous and heterozygous GH transgenesis alters fatty acid composition and content in the liver of Amago salmon (Oncorhynchus masou ishikawae). Biol Open 2012; 1:1035-42. [PMID: 23213381 PMCID: PMC3507178 DOI: 10.1242/bio.20121263] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 07/02/2012] [Indexed: 12/20/2022] Open
Abstract
Growth hormone (GH) transgenic Amago (Oncorhynchus masou ishikawae), containing the sockeye GH1 gene fused with metallothionein-B promoter from the same species, were generated and the physiological condition through lipid metabolism compared among homozygous (Tg/Tg) and heterozygous GH transgenic (Tg/+) Amago and the wild type control (+/+). Previously, we have reported that the adipose tissue was generally smaller in GH transgenic fish compared to the control, and that the Δ-6 fatty acyl desaturase gene was down-regulated in the Tg/+ fish. However, fatty acid (FA) compositions have not been measured previously in these fish. In this study we compared the FAs composition and content in the liver using gas chromatography. Eleven kinds of FA were detected. The composition of saturated and monounsaturated fatty acids (SFA and MUFA) such as myristic acid (14:0), palmitoleic acid (16:1n-7), and cis-vaccenic acid (cis-18:1n-7) was significantly (P<0.05) decreased in GH transgenic Amago. On the other hand, the composition of polyunsaturated fatty acids (PUFAs) such as linoleic acid (18:2n-6), arachidonic acid (20:4n-6), and docosapentaenoic acid (22:5n-3) was significantly (P<0.05) increased. Levels of serum glucose and triacylglycerol were significantly (P<0.05) decreased in the GH transgenics compared with +/+ fish. Furthermore, 3′-tag digital gene expression profiling was performed using liver tissues from Tg/Tg and +/+ fish, and showed that Mid1 interacting protein 1 (Mid1ip1), which is an important factor to activate Acetyl-CoA carboxylase (ACC), was down-regulated in Tg/Tg fish, while genes involved in FA catabolism were up-regulated, including long-chain-fatty-acid–CoA ligase 1 (ACSL1) and acyl-coenzyme A oxidase 3 (ACOX3). These data suggest that liver tissue from GH transgenic Amago showed starvation by alteration in glucose and lipid metabolism due to GH overexpression. The decrease of serum glucose suppressed Mid1ip1, and caused a decrease of de novo FA synthesis, resulting in a decrease of SFA and MUFA. This induced expression of ACSL1 and ACOX3 to produce energy through β-oxidation in the GH transgenic Amago.
Collapse
Affiliation(s)
- Manabu Sugiyama
- Nihon University College of Bioresource Sciences , Kameino 1866, Fujisawa 252-0880 , Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Raven PA, Sakhrani D, Beckman B, Neregård L, Sundström LF, Björnsson BT, Devlin RH. Growth and endocrine effects of recombinant bovine growth hormone treatment in non-transgenic and growth hormone transgenic coho salmon. Gen Comp Endocrinol 2012; 177:143-52. [PMID: 22433940 DOI: 10.1016/j.ygcen.2012.03.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Revised: 02/28/2012] [Accepted: 03/01/2012] [Indexed: 11/19/2022]
Abstract
To examine the relative growth, endocrine, and gene expression effects of growth hormone (GH) transgenesis vs. GH protein treatment, wild-type non-transgenic and GH transgenic coho salmon were treated with a sustained-release formulation of recombinant bovine GH (bGH; Posilac). Fish size, specific growth rate (SGR), and condition factor (CF) were monitored for 14 weeks, after which endocrine parameters were measured. Transgenic fish had much higher growth, SGR and CF than non-transgenic fish, and bGH injection significantly increased weight and SGR in non-transgenic but not transgenic fish. Plasma salmon GH concentrations decreased with bGH treatment in non-transgenic but not in transgenic fish where levels were similar to controls. Higher GH mRNA levels were detected in transgenic muscle and liver but no differences were observed in GH receptor (GHR) mRNA levels. In non-transgenic pituitary, GH and GHR mRNA levels per mg pituitary decreased with bGH dose to levels seen in transgenic salmon. Plasma IGF-I was elevated with bGH dose only in non-transgenic fish, while transgenic fish maintained an elevated level of IGF-I with or without bGH treatment. A similar trend was seen for liver IGF-I mRNA levels. Thus, bGH treatment increased fish growth and influenced feedback on endocrine parameters in non-transgenic but not in transgenic fish. A lack of further growth stimulation of GH transgenic fish suggests that these fish are experiencing maximal growth stimulation via GH pathways.
Collapse
Affiliation(s)
- P A Raven
- Department of Fisheries & Oceans, Centre for Aquaculture & Environmental Research, West Vancouver, BC, Canada V7V 1N6
| | | | | | | | | | | | | |
Collapse
|
17
|
Effects of growth hormone on the salmon pituitary proteome. J Proteomics 2012; 75:1718-31. [DOI: 10.1016/j.jprot.2011.12.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 11/30/2011] [Accepted: 12/04/2011] [Indexed: 01/02/2023]
|
18
|
Shved N, Berishvili G, Mazel P, Baroiller JF, Eppler E. Growth hormone (GH) treatment acts on the endocrine and autocrine/paracrine GH/IGF-axis and on TNF-α expression in bony fish pituitary and immune organs. FISH & SHELLFISH IMMUNOLOGY 2011; 31:944-952. [PMID: 21903170 DOI: 10.1016/j.fsi.2011.08.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 08/12/2011] [Accepted: 08/19/2011] [Indexed: 05/31/2023]
Abstract
There exist indications that the growth hormone (GH)/insulin-like growth factor (IGF) axis may play a role in fish immune regulation, and that interactions occur via tumour necrosis factor (TNF)-α at least in mammals, but no systematic data exist on potential changes in GH, IGF-I, IGF-II, GH receptor (GHR) and TNF-α expression after GH treatment. Thus, we investigated in the Nile tilapia the influence of GH injections by real-time qPCR at different levels of the GH/IGF-axis (brain, pituitary, peripheral organs) with special emphasis on the immune organs head kidney and spleen. Endocrine IGF-I served as positive control for GH treatment efficiency. Basal TNF-α gene expression was detected in all organs investigated with the expression being most pronounced in brain. Two consecutive intraperitoneal injections of bream GH elevated liver IGF-I mRNA and plasma IGF-I concentration. Also liver IGF-II mRNA and TNF-α were increased while the GHR was downregulated. In brain, no change occurred in the expression levels of all genes investigated. GH gene expression was exclusively detected in the pituitary where the GH injections elevated both GH and IGF-I gene expression. In the head kidney, GH upregulated IGF-I mRNA to an even higher extent than liver IGF-I while IGF-II and GHR gene expressions were not affected. Also in the spleen, no change occurred in GHR mRNA, however, IGF-I and IGF-II mRNAs were increased. In correlation, in situ hybridisation showed a markedly higher amount of IGF-I mRNA in head kidney and spleen after GH injection. In both immune tissues, TNF-α gene expression showed a trend to decrease after GH treatment. The stimulation of IGF-I and also partially of IGF-II expression in the fish immune organs by GH indicates a local role of the IGFs in immune organ regulation while the differential changes in TNF-α support the in mammals postulated interactions with the GH/IGF-axis which demand for further investigations.
Collapse
Affiliation(s)
- N Shved
- Research Group Neuro-endocrine-immune Interactions, Institute of Anatomy, University of Zürich, Winterthurerstr. 190, CH-8057 Zürich, Switzerland
| | | | | | | | | |
Collapse
|
19
|
Cows I, Bolland J, Nunn A, Kerins G, Stein J, Blackburn J, Hart A, Henry C, Britton JR, Coop G, Peeler E. Defining environmental risk assessment criteria for genetically modified fishes to be placed on the EU market. ACTA ACUST UNITED AC 2010. [DOI: 10.2903/sp.efsa.2010.en-69] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- I.G. Cows
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - J.D. Bolland
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - A.D. Nunn
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - G. Kerins
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - J. Stein
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - J. Blackburn
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - A. Hart
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - C. Henry
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - J. R. Britton
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - G. Coop
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| | - E. Peeler
- Hull International Fisheries Institute, Food and Environmental Research Agency, Bournemouth University, Center for Environment, Fisheries and Aquaculture Science
| |
Collapse
|
20
|
Abstract
Pituitary somatotrophs secrete growth hormone (GH) into the bloodstream, to act as a hormone at receptor sites in most, if not all, tissues. These endocrine actions of circulating GH are abolished after pituitary ablation or hypophysectomy, indicating its pituitary source. GH gene expression is, however, not confined to the pituitary gland, as it occurs in neural, immune, reproductive, alimentary, and respiratory tissues and in the integumentary, muscular, skeletal, and cardiovascular systems, in which GH may act locally rather than as an endocrine. These actions are likely to be involved in the proliferation and differentiation of cells and tissues prior to the ontogeny of the pituitary gland. They are also likely to complement the endocrine actions of GH and are likely to maintain them after pituitary senescence and the somatopause. Autocrine or paracrine actions of GH are, however, sometimes mediated through different signaling mechanisms to those mediating its endocrine actions and these may promote oncogenesis. Extrapituitary GH may thus be of physiological and pathophysiological significance.
Collapse
Affiliation(s)
- S Harvey
- Department of Physiology, University of Alberta, 7-41 Medical Sciences Building, Edmonton, AB T6G 2H7, Canada,
| |
Collapse
|
21
|
Acosta J, Carpio Y, Morales R, Águila JC, Acanda Y, Herrera F, Estrada MP. New insights into the biological activity and secretion properties of a polypeptide derived from tilapia somatotropin. Comp Biochem Physiol B Biochem Mol Biol 2010; 156:264-72. [DOI: 10.1016/j.cbpb.2010.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 04/05/2010] [Accepted: 04/06/2010] [Indexed: 11/30/2022]
|
22
|
Lõhmus M, Sundström LF, Björklund M, Devlin RH. Genotype-temperature interaction in the regulation of development, growth, and morphometrics in wild-type, and growth-hormone transgenic coho salmon. PLoS One 2010; 5:e9980. [PMID: 20376315 PMCID: PMC2848618 DOI: 10.1371/journal.pone.0009980] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Accepted: 03/11/2010] [Indexed: 11/18/2022] Open
Abstract
Background The neuroendocrine system is an important modulator of phenotype, directing cellular genetic responses to external cues such as temperature. Behavioural and physiological processes in poikilothermic organisms (e.g. most fishes), are particularly influenced by surrounding temperatures. Methodology/Principal Findings By comparing the development and growth of two genotypes of coho salmon (wild-type and transgenic with greatly enhanced growth hormone production) at six different temperatures, ranging between 8° and 18°C, we observed a genotype-temperature interaction and possible trend in directed neuroendocrine selection. Differences in growth patterns of the two genotypes were compared by using mathematical models, and morphometric analyses of juvenile salmon were performed to detect differences in body shape. The maximum hatching and alevin survival rates of both genotypes occurred at 12°C. At lower temperatures, eggs containing embryos with enhanced GH production hatched after a shorter incubation period than wild-type eggs, but this difference was not apparent at and above 16°C. GH transgenesis led to lower body weights at the time when the yolk sack was completely absorbed compared to the wild genotype. The growth of juvenile GH-enhanced salmon was to a greater extent stimulated by higher temperatures than the growth of the wild-type. Increased GH production significantly influenced the shape of the salmon growth curves. Conclusions Growth hormone overexpression by transgenesis is able to stimulate the growth of coho salmon over a wide range of temperatures. Temperature was found to affect growth rate, survival, and body morphology between GH transgenic and wild genotype coho salmon, and differential responses to temperature observed between the genotypes suggests they would experience different selective forces should they ever enter natural ecosystems. Thus, GH transgenic fish would be expected to differentially respond and adapt to shifts in environmental conditions compared with wild type, influencing their ability to survive and interact in ecosystems. Understanding these relationships would assist environmental risk assessments evaluating potential ecological effects.
Collapse
Affiliation(s)
- Mare Lõhmus
- Centre for Aquaculture and Environmental Research, Fisheries and Oceans Canada, West Vancouver, British Columbia, Canada.
| | | | | | | |
Collapse
|
23
|
Lõhmus M, Björklund M, Sundström LF, Devlin RH. Effects of temperature and growth hormone on individual growth trajectories of wild-type and transgenic coho salmon Oncorhynchus kisutch. JOURNAL OF FISH BIOLOGY 2010; 76:641-654. [PMID: 20666902 DOI: 10.1111/j.1095-8649.2009.02521.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
In this study, individual growth patterns of wild-type and growth-enhanced coho salmon Oncorhynchus kisutch at 8, 12 and 16 degrees C water temperature were followed. Despite large differences among individuals in growth rates, there was generally little variation in the shape of the growth curves among O. kisutch individuals of both genotypes and at all temperatures. Typically, individuals that were relatively large initially were also relatively large at the end of the growth period. The limitation in variation was more pronounced in the growth-enhanced O. kisutch than in the wild type, where the relative size of some individuals reared at 12 and 8 degrees C changed by the end of the trial. As a warmer temperature seems to decrease the plasticity of growth trajectories in wild-type fish, it is possible that global warming will influence the ability of wild fish to adapt their growth to changing conditions.
Collapse
Affiliation(s)
- M Lõhmus
- Department of Fisheries and Oceans-University of British Columbia, Centre for Aquaculture and Environmental Research, West Vancouver Laboratory, BC, Canada
| | | | | | | |
Collapse
|
24
|
Martyniuk CJ, Trudeau VL. Fish endocrinology meets functional genomics: what exactly is the message? Gen Comp Endocrinol 2009; 164:132-4. [PMID: 19481084 DOI: 10.1016/j.ygcen.2009.05.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2009] [Accepted: 05/21/2009] [Indexed: 11/26/2022]
|
25
|
Zhong S, Wang YP, Pei DS, Luo DJ, Liao LJ, Zhu ZY. A one-year investigation of the relationship between serum GH levels and the growth of F(4) transgenic and non-transgenic common carp Cyprinus carpio. JOURNAL OF FISH BIOLOGY 2009; 75:1092-1100. [PMID: 20738600 DOI: 10.1111/j.1095-8649.2009.02399.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
It has been demonstrated that growth hormone (GH) transgenic fish often posses a trait for fast growth. Here, we investigated the growth of F(4)'all-fish' GH transgenic carp Cyprinus carpio and their serum GH levels for a year. The results showed that F(4) all-fish GH transgenic carp were significantly larger in body mass (c. two-fold, P < 0.001) and body length (c. 1.3 fold, P < 0.001), compared with the non-transgenic group. The discrepancy of serum GH levels between the transgenic carp group and control group is 54 fold, when the water temperature was 12-34 degrees C. When the water temperature decreased to 3.5 degrees C in January, the discrepancy was 256 fold. The serum GH level of the transgenic group was relatively constant, while that of control varied greatly based on month and water temperature. The changes of growth rates between the transgenic group and the control group were similar for a year. Taken together, the results indicated that F(4) all-fish GH transgenic carp had not only higher and constant serum GH levels but also a significant fast-growing effect, compared with the control. To our knowledge, this is the first report on a one-year investigation of growth trait and serum growth hormone level in F(4) all-fish GH transgenic carp.
Collapse
Affiliation(s)
- S Zhong
- College of Life Science, Wuhan University, Wuhan 430072, China
| | | | | | | | | | | |
Collapse
|
26
|
Eppler E, Berishvili G, Mazel P, Caelers A, Hwang G, Maclean N, Reinecke M. Distinct organ-specific up- and down-regulation of IGF-I and IGF-II mRNA in various organs of a GH-overexpressing transgenic Nile tilapia. Transgenic Res 2009; 19:231-40. [PMID: 19669925 DOI: 10.1007/s11248-009-9314-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Accepted: 07/28/2009] [Indexed: 12/13/2022]
Abstract
Several lines of GH-overexpressing fish have been produced and characterized concerning organ integrity, growth, fertility and health but few and contradictory data are available on IGF-I that mediates most effects of GH. Furthermore, nothing is known on IGF-II. Thus, the expression of both IGFs in liver and various extrahepatic sites of adult transgenic (GH-overexpressing) tilapia and age-matched wild-type fish was determined by real-time PCR. Both IGF-I and IGF-II mRNA were found in all organs investigated and were increased in gills, kidney, intestine, heart, testes, skeletal muscle and brain of the transgenics (IGF-I: 1.4-4-fold; IGF-II: 1.7-4.2-fold). Except for liver, brain and testis the increase in IGF-I mRNA was higher than that in IGF-II mRNA. In pituitary, no significant change in IGF-I or IGF-II mRNA was detected. In spleen, however, IGF-I and IGF-II mRNA were both decreased in the transgenics, IGF-I mRNA even by the 19-fold. In agreement, in situ hybridisation revealed a largely reduced number of IGF-I mRNA-containing leukocytes and macrophages when compared to wild-type. These observations may contribute to better understanding the reported impaired health of GH-transgenic fish. Growth enhancement of the transgenics may be due to the increased expression of both IGF-I and IGF-II in extrahepatic sites. It is also reasonable that the markedly enhanced expression of liver IGF-II mRNA that may mimick an early developmental stage is a further reason for increased growth.
Collapse
Affiliation(s)
- Elisabeth Eppler
- Research Group Neuro-Endocrine-Immune Interactions, Institute of Anatomy, University of Zürich, Winterthurerstr. 190, CH-8057 Zürich, Switzerland
| | | | | | | | | | | | | |
Collapse
|
27
|
Sundström LF, Tymchuk WE, Lõhmus M, Devlin RH. Sustained predation effects of hatchery-reared transgenic coho salmonOncorhynchus kisutchin semi-natural environments. J Appl Ecol 2009. [DOI: 10.1111/j.1365-2664.2009.01668.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
28
|
Xu M, Volkoff H. Cloning, tissue distribution and effects of food deprivation on pituitary adenylate cyclase activating polypeptide (PACAP)/PACAP-related peptide (PRP) and preprosomatostatin 1 (PPSS 1) in Atlantic cod (Gadus morhua). Peptides 2009; 30:766-76. [PMID: 19135491 DOI: 10.1016/j.peptides.2008.12.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2008] [Revised: 12/09/2008] [Accepted: 12/09/2008] [Indexed: 10/21/2022]
Abstract
Full-length complementary deoxyribonucleic acid sequences encoding pituitary adenylate cyclase activating polypeptide (PACAP)/PACAP-related peptide (PRP) and preprosomatostatin 1 (PPSS 1) were cloned from Atlantic cod (Gadus morhua) hypothalamus using reverse transcription and rapid amplification of complementary deoxyribonucleic acid ends. Semi-quantitative reverse transcriptase polymerase chain reaction shows that PRP/PACAP mRNA and PPSS 1 mRNA are widely distributed throughout cod brain. During development, PRP/PACAP and PPSS 1 were detected at the 30-somite stage and pre-hatching stage, respectively, and expression levels gradually increased up to the hatched larvae. PPSS 1, but not PRP/PACAP, appeared to be affected by food availability during early development. In juvenile cod, PPSS 1 expression levels increased and remained significantly higher than that of control fed fish throughout 30 days of starvation and during a subsequent 10 days refeeding period. In contrast, PRP/PACAP expression levels were not affected by 30 days of food deprivation, but a significant increase in expression levels was observed during the 10 days refeeding period in the experimental food-deprived group as compared to the control fed group. Our results suggest that PRP/PACAP and PPSS 1 may be involved in the complex regulation of growth, feeding and metabolism during food deprivation and refeeding in Atlantic cod.
Collapse
Affiliation(s)
- Meiyu Xu
- Departments of Biology, Memorial University of Newfoundland, St John's, Canada.
| | | |
Collapse
|
29
|
Devlin RH, Sakhrani D, Tymchuk WE, Rise ML, Goh B. Domestication and growth hormone transgenesis cause similar changes in gene expression in coho salmon (Oncorhynchus kisutch). Proc Natl Acad Sci U S A 2009; 106:3047-52. [PMID: 19223591 PMCID: PMC2651260 DOI: 10.1073/pnas.0809798106] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2008] [Indexed: 11/18/2022] Open
Abstract
Domestication has been extensively used in agricultural animals to modify phenotypes such as growth rate. More recently, transgenesis of growth factor genes [primarily growth hormone (GH)] has also been explored as a rapid approach to accelerating performance of agricultural species. Growth rates of many fishes respond dramatically to GH gene transgenesis, whereas genetic engineering of domestic mammalian livestock has resulted in relatively modest gains. The most dramatic effects of GH transgenesis in fish have been seen in relatively wild strains that have undergone little or no selection for enhanced growth, whereas genetic modification of livestock necessarily has been performed in highly domesticated strains that already possess very rapid growth. Such fast-growing domesticates may be refractory to further stimulation if the same regulatory pathways are being exploited by both genetic approaches. By directly comparing gene expression in wild-type, domestic, and GH transgenic strains of coho salmon, we have found that domestication and GH transgenesis are modifying similar genetic pathways. Genes in many different physiological pathways show modified expression in domestic and GH transgenic strains relative to wild-type, but effects are strongly correlated. Genes specifically involved in growth regulation (IGF1, GHR, IGF-II, THR) are also concordantly regulated in domestic and transgenic fish, and both strains show elevated levels of circulating IGF1. Muscle expression of GH in nontransgenic strains was found to be elevated in domesticated fish relative to wild type, providing a possible mechanism for growth enhancement. These data have implications for genetic improvement of existing domesticated species and risk assessment and regulation of emerging transgenic strains.
Collapse
Affiliation(s)
- Robert H Devlin
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, Canada V7V 1N6.
| | | | | | | | | |
Collapse
|
30
|
Verburg‐Van Kemenade BL, Stolte EH, Metz JR, Chadzinska M. Chapter 7 Neuroendocrine–Immune Interactions in Teleost Fish. FISH PHYSIOLOGY 2009. [DOI: 10.1016/s1546-5098(09)28007-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
31
|
von Schalburg KR, Yazawa R, de Boer J, Lubieniecki KP, Goh B, Straub CA, Beetz-Sargent MR, Robb A, Davidson WS, Devlin RH, Koop BF. Isolation, characterization and comparison of Atlantic and Chinook salmon growth hormone 1 and 2. BMC Genomics 2008; 9:522. [PMID: 18980692 PMCID: PMC2584663 DOI: 10.1186/1471-2164-9-522] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2008] [Accepted: 11/03/2008] [Indexed: 12/04/2022] Open
Abstract
Background Growth hormone (GH) is an important regulator of skeletal growth, as well as other adapted processes in salmonids. The GH gene (gh) in salmonids is represented by duplicated, non-allelic isoforms designated as gh1 and gh2. We have isolated and characterized gh-containing bacterial artificial chromosomes (BACs) of both Atlantic and Chinook salmon (Salmo salar and Oncorhynchus tshawytscha) in order to further elucidate our understanding of the conservation and regulation of these loci. Results BACs containing gh1 and gh2 from both Atlantic and Chinook salmon were assembled, annotated, and compared to each other in their coding, intronic, regulatory, and flanking regions. These BACs also contain the genes for skeletal muscle sodium channel oriented in the same direction. The sequences of the genes for interferon alpha-1, myosin alkali light chain and microtubule associated protein Tau were also identified, and found in opposite orientations relative to gh1 and gh2. Viability of each of these genes was examined by PCR. We show that transposon insertions have occurred differently in the promoters of gh, within and between each species. Other differences within the promoters and intronic and 3'-flanking regions of the four gh genes provide evidence that they have distinct regulatory modes and possibly act to function differently and/or during different times of salmonid development. Conclusion A core proximal promoter for transcription of both gh1 and gh2 is conserved between the two species of salmon. Nevertheless, transposon integration and regulatory element differences do exist between the promoters of gh1 and gh2. Additionally, organization of transposon families into the BACs containing gh1 and for the BACs containing gh2, are very similar within orthologous regions, but much less clear conservation is apparent in comparisons between the gh1- and gh2-containing paralogous BACs for the two fish species. This is consistent with the hypothesis that a burst of transposition activity occurred during the speciation events which led to Atlantic and Pacific salmon. The Chinook and other Oncorhynchus GH1s are strikingly different in comparison to the other GHs and this change is not apparent in the surrounding non-coding sequences.
Collapse
Affiliation(s)
- Kristian R von Schalburg
- Centre for Biomedical Research, University of Victoria, Victoria, British Columbia, V8W 3N5, Canada.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Raven PA, Uh M, Sakhrani D, Beckman BR, Cooper K, Pinter J, Leder EH, Silverstein J, Devlin RH. Endocrine effects of growth hormone overexpression in transgenic coho salmon. Gen Comp Endocrinol 2008; 159:26-37. [PMID: 18713628 DOI: 10.1016/j.ygcen.2008.07.011] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2008] [Revised: 07/22/2008] [Accepted: 07/23/2008] [Indexed: 11/30/2022]
Abstract
Non-transgenic (wild-type) coho salmon (Oncorhynchus kisutch), growth hormone (GH) transgenic salmon (with highly elevated growth rates), and GH transgenic salmon pair fed a non-transgenic ration level (and thus growing at the non-transgenic rate) were examined for plasma hormone concentrations, and liver, muscle, hypothalamus, telencephalon, and pituitary mRNA levels. GH transgenic salmon exhibited increased plasma GH levels, and enhanced liver, muscle and hypothalamic GH mRNA levels. Insulin-like growth factor-I (IGF-I) in plasma, and growth hormone receptor (GHR) and IGF-I mRNA levels in liver and muscle, were higher in fully fed transgenic than non-transgenic fish. GHR mRNA levels in transgenic fish were unaffected by ration-restriction, whereas plasma GH was increased and plasma IGF-I and liver IGF-I mRNA were decreased to wild-type levels. These data reveal that strong nutritional modulation of IGF-I production remains even in the presence of constitutive ectopic GH expression in these transgenic fish. Liver GHR membrane protein levels were not different from controls, whereas, in muscle, GHR levels were elevated approximately 5-fold in transgenic fish. Paracrine stimulation of IGF-I by ectopic GH production in non-pituitary tissues is suggested by increased basal cartilage sulphation observed in the transgenic salmon. Levels of mRNA for growth hormone-releasing hormone (GHRH) and cholecystokinin (CCK) did not differ between groups. Despite its role in appetite stimulation, neuropeptide Y (NPY) mRNA was not found to be elevated in transgenic groups.
Collapse
Affiliation(s)
- P A Raven
- Department of Fisheries & Oceans, Centre for Aquaculture & Environmental Research, West Vancouver, BC, Canada
| | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Aikio S, Valosaari KR, Ranta E, Kaitala V, Lundberg P. Invasion under a trade-off between density dependence and maximum growth rate. POPUL ECOL 2008. [DOI: 10.1007/s10144-008-0085-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
34
|
Yada T. Growth hormone and fish immune system. Gen Comp Endocrinol 2007; 152:353-8. [PMID: 17382328 DOI: 10.1016/j.ygcen.2007.01.045] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Revised: 12/26/2006] [Accepted: 01/01/2007] [Indexed: 11/23/2022]
Abstract
This paper reviews the immunomodulatory effects, extra-pituitary expression and paracrine action of growth hormone (GH), and a possible role of GH/insulin-like growth factor-I (IGF-I) axis in the immune system of teleost fish. In some euryhaline fish, the activation of immune functions observed during seawater acclimation appears to be associated with the osmoregulatory action of GH. Administration of GH enhances many aspects of immune functions including non-specific defences; cytotoxic, phagocytic, haemolytic and lysozyme activities. GH also activates immunoglobulin production as a specific defense and increases ceruloplasmin levels as an acute-phase protein. The GH gene is also expressed in many extra-pituitary tissues of fish, especially in lymphoid organs and cells. Several endocrine factors appear to act on immune function through modification of GH secretion from fish leucocytes. Exposure of phagocytic leucocytes of tilapia to IGF-I in vitro stimulated proliferation and superoxide production associated with phagocytosis. Exposure to GH had no significant effect on IGF-I secretion from tilapia leucocytes, despite of the fact that they secreted significant amounts of IGF-I. GH and IGF-I appear to act in a paracrine manner in the regulation of the teleostean immune system. Further studies are necessary to characterize the interactions of GH with other endocrine and paracrine factors.
Collapse
Affiliation(s)
- Takashi Yada
- Freshwater Fisheries Research Division, National Research Institute of Fisheries Science, Nikko, Tochigi 321-1661, Japan.
| |
Collapse
|
35
|
Hallerman EM, McLean E, Fleming IA. Effects of growth hormone transgenes on the behavior and welfare of aquacultured fishes: A review identifying research needs. Appl Anim Behav Sci 2007. [DOI: 10.1016/j.applanim.2006.09.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
36
|
Mori T, Hiraka I, Kurata Y, Kawachi H, Mano N, Devlin RH, Nagoya H, Araki K. Changes in hepatic gene expression related to innate immunity, growth and iron metabolism in GH-transgenic amago salmon (Oncorhynchus masou) by cDNA subtraction and microarray analysis, and serum lysozyme activity. Gen Comp Endocrinol 2007; 151:42-54. [PMID: 17222841 DOI: 10.1016/j.ygcen.2006.11.012] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 11/01/2006] [Accepted: 11/15/2006] [Indexed: 11/29/2022]
Abstract
Growth hormone (GH) transgenic amago salmon (Oncorhynchus masou) were generated with a construct containing the sockeye salmon GH1 gene fused to the metallothionein-B (MT-B) promoter from the same species. This transgene directed significant growth enhancement with transgenic fish reaching approximately four to five times greater weight than control salmon in F(2) and F(3) generations. This drastic growth enhancement by GH transgene is well known in fish species compared with mammals, however, such fish can show morphological abnormalities and physiological disorders like other GH transgenic animals. GH is known to have many acute effects, but currently there are no data describing the chronic effects of over-expression of GH on various hepatic genes in GH transgenic fish. Hepatic gene expression is anticipated to play very important roles in many physiological functions and growth performance of transgenic and control salmon. To examine these effects, we performed subtractive hybridization (using cDNA generated from liver RNA) in both directions to identify genes both increased and decreased in transgenic salmon relative to controls (576 clones were isolated and sequenced in total). Heme oxygenase, vitelline envelope protein, Acyl-coA binding protein, NADH dehydrogenase, mannose binding lectin-associated serine protease, hemopexin-like protein, leucyte-derived chemotaxin2 (LECT2), and many other genes were obtained in higher clone frequencies suggesting enhanced expression. In contrast, complement C3-1, lectin, rabin, alcohol dehydrogenase, Tc1-like transposase, Delta6-desaturase, and pentraxin genes were obtained in lower frequencies. Microarray analysis was also performed to obtain quantitative expression data for these subtracted cDNA clones. Analysis of fish across seasons was also conducted using both F(2) and F(3) salmon. Results of the microarray data essentially corresponded with those of the subtraction data when both F(2) and F(3) fish were completely immature, but the expression pattern was changed when fish approached maturation. Genes showing enhanced expression in GH transgenic fish in F(2) and F(3) by array analysis were vitelline envelope protein, hemopexin-like protein, heme-oxygenase, inter alpha-trypsin inhibitor, LECT2, GTP cyclohydrolase I feedback regulatory protein (GFRP), and bikunin. Reduced expression genes were lectin, Delta6-desaturase, apolipoprotein, and pentraxin. In particular, lectin was found to be highly suppressed in all F(2) and immature F(3) salmon. Further, serum lysozyme activity, one of innate immunity, was significantly (p<0.05) decreased in both F(2) and F(3) GH transgenic fish. These results indicate that the GH transgene fish had altered hepatic gene expression relating to iron-metabolism, innate immunity, reproduction, and growth.
Collapse
Affiliation(s)
- Tsukasa Mori
- Laboratory of Marine Molecular Biochemistry, Department of Nihon University College of Bioresource Sciences, Kameino 1866, Fujisawa 252-8510, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Canosa LF, Chang JP, Peter RE. Neuroendocrine control of growth hormone in fish. Gen Comp Endocrinol 2007; 151:1-26. [PMID: 17286975 DOI: 10.1016/j.ygcen.2006.12.010] [Citation(s) in RCA: 155] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Revised: 12/12/2006] [Accepted: 12/22/2006] [Indexed: 10/23/2022]
Abstract
The biological actions of growth hormone (GH) are pleiotropic, including growth promotion, energy mobilization, gonadal development, appetite, and social behavior. Accordingly, the regulatory network for GH is complex and includes many endocrine and environmental factors. In fish, the neuroendocrine control of GH is multifactorial with multiple inhibitors and stimulators of pituitary GH secretion. In fish, GH release is under a tonic negative control exerted mainly by somatostatin. Sex steroid hormones and nutritional status influence the level of brain expression and effectiveness of some of these GH neuroendocrine regulatory factors, suggesting that their relative importance differs under different physiological conditions. At the pituitary level, some, if not all, somatotropes can respond to multiple regulators. Therefore, ligand- and function-specificity, as well as the integrative responses to multiple signals must be achieved at the level of signal transduction mechanisms. Results from investigations on a limited number of stimulatory and inhibitory GH-release regulators indicate that activation of different but convergent intracellular pathways and the utilization of specific intracellular Ca(2+) stores are some of the strategies utilized. However, more work remains to be done in order to better understand the integrative mechanisms of signal transduction at the somatotrope level and the relevance of various GH regulators in different physiological circumstances.
Collapse
Affiliation(s)
- Luis Fabián Canosa
- Department of Biological Sciences, University of Alberta, Edmonton, Alta., Canada T6G 2E9
| | | | | |
Collapse
|
38
|
Sundström LF, Lõhmus M, Tymchuk WE, Devlin RH. Gene-environment interactions influence ecological consequences of transgenic animals. Proc Natl Acad Sci U S A 2007; 104:3889-94. [PMID: 17360448 PMCID: PMC1820679 DOI: 10.1073/pnas.0608767104] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Production of transgenic animals has raised concern regarding their potential ecological impact should they escape or be released to the natural environment. This concern has arisen mainly from research on laboratory-reared animals and theoretical modeling exercises. In this study, we used biocontained naturalized stream environments and conventional hatchery environments to show that differences in phenotype between transgenic and wild genotypes depend on rearing conditions and, critically, that such genotype-by-environment interactions may influence subsequent ecological effects in nature. Genetically wild and growth hormone transgenic coho salmon (Oncorhynchus kisutch) were reared from the fry stage under either standard hatchery conditions or under naturalized stream conditions. When reared under standard hatchery conditions, the transgenic fish grew almost three times longer than wild conspecifics and had (under simulated natural conditions) stronger predation effects on prey than wild genotypes (even after compensation for size differences). In contrast, when fish were reared under naturalized stream conditions, transgenic fish were only 20% longer than the wild fish, and the magnitude of difference in relative predation effects was much reduced. These data show that genotype-by-environment interactions can influence the relative phenotype of transgenic and wild-type organisms and that extrapolations of ecological consequences from phenotypes developed in the unnatural laboratory environment may lead to an overestimation or underestimation of ecological risk. Thus, for transgenic organisms that may not be released to nature, the establishment of a range of highly naturalized environments will be critical for acquiring reliable experimental data to be used in risk assessments.
Collapse
Affiliation(s)
- L. F. Sundström
- Centre for Aquaculture and Environmental Research, Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, Canada V7V 1N6
| | - M. Lõhmus
- Centre for Aquaculture and Environmental Research, Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, Canada V7V 1N6
| | - W. E. Tymchuk
- Centre for Aquaculture and Environmental Research, Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, Canada V7V 1N6
| | - Robert H. Devlin
- Centre for Aquaculture and Environmental Research, Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, Canada V7V 1N6
- *To whom correspondence should be addressed. E-mail:
| |
Collapse
|
39
|
Filby AL, Tyler CR. Cloning and characterization of cDNAs for hormones and/or receptors of growth hormone, insulin-like growth factor-I, thyroid hormone, and corticosteroid and the gender-, tissue-, and developmental-specific expression of their mRNA transcripts in fathead minnow (Pimephales promelas). Gen Comp Endocrinol 2007; 150:151-63. [PMID: 16970945 DOI: 10.1016/j.ygcen.2006.07.014] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Revised: 07/19/2006] [Accepted: 07/23/2006] [Indexed: 11/16/2022]
Abstract
Growth hormone (GH), insulin-like growth factor-I (IGF-I), thyroid hormones, and corticosteroids play central roles in a wide range of body functions but, in fish, information on their interactions is limited. These axes of the endocrine system are also potential targets for disruption of signaling pathways by hormone-mimicking chemicals, but have received little study. Molecular approaches offer an effective way to help unravel these endocrine interactions but require the appropriate gene-specific assays to do so. In this study, the cDNAs for a suite of hormones and/or receptors involved in signaling for the effects of GH and IGF-I [GH, GH receptor (GHR), IGF-I, IGF-I receptor (IGF-IR)], thyroid hormones [thyroid hormone receptor alpha (TRalpha) and beta (TRbeta)], and corticosteroids [glucocorticoid receptor (GR)] were cloned from the fathead minnow (Pimephales promelas; fhm), and the tissue-, developmental-, and gender-related expression of their mRNA transcripts established. By polymerase chain reaction (PCR) strategy, we obtained full-length 1123-bp GH, 817-bp IGF-I, 1584-bp TRbeta, and 2571-bp GR cDNAs, coding for 210 amino acid (aa) GH, 161 aa IGF-I, 378 aa TRbeta, and 745 aa GR putative proteins, and partial-length 158-bp GHR, 811-bp IGF-IR, and 446-bp TRalpha cDNAs. Real-time PCR analyses revealed broad tissue expression for the target mRNAs; all targets were expressed in brain, pituitary, gill, liver, gonad, intestine, and muscle, with the exception of GH that was expressed only in the pituitary and gonad. Expression patterns in both juvenile and adult fhm were complex, with both temporal-, tissue-, and sex-specific characteristics. For example, hepatic expressions of GHR, IGF-I, and IGF-IR were far higher in males than in females, possibly reflecting the sex-related dimorphism in growth that occurs in this species, and TRalpha and TRbeta showed divergent expression patterns during development (where TRbeta predominated) and in adult tissues implying some distinct roles for the two TR subtypes.
Collapse
MESH Headings
- Adrenal Cortex Hormones/genetics
- Adrenal Cortex Hormones/metabolism
- Animals
- Cloning, Molecular
- Cyprinidae/genetics
- Cyprinidae/growth & development
- Cyprinidae/metabolism
- DNA, Complementary/analysis
- Female
- Gene Expression Regulation, Developmental
- Growth Hormone/genetics
- Growth Hormone/metabolism
- Insulin-Like Growth Factor I/genetics
- Insulin-Like Growth Factor I/metabolism
- Male
- RNA, Messenger/analysis
- RNA, Messenger/metabolism
- Receptor, IGF Type 1/genetics
- Receptor, IGF Type 1/metabolism
- Receptors, Somatotropin/genetics
- Receptors, Somatotropin/metabolism
- Receptors, Thyroid Hormone/genetics
- Receptors, Thyroid Hormone/metabolism
- Sex Factors
- Thyroid Hormones/genetics
- Thyroid Hormones/metabolism
- Tissue Distribution
Collapse
Affiliation(s)
- Amy L Filby
- Environmental and Molecular Fish Biology Group, School of Biosciences, Hatherly Laboratories, University of Exeter, Prince of Wales Road, Exeter, Devon EX4 4PS, UK.
| | | |
Collapse
|
40
|
Wong AOL, Zhou H, Jiang Y, Ko WKW. Feedback regulation of growth hormone synthesis and secretion in fish and the emerging concept of intrapituitary feedback loop. Comp Biochem Physiol A Mol Integr Physiol 2006; 144:284-305. [PMID: 16406825 DOI: 10.1016/j.cbpa.2005.11.021] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2005] [Revised: 11/21/2005] [Accepted: 11/21/2005] [Indexed: 11/21/2022]
Abstract
Growth hormone (GH) is known to play a key role in the regulation of body growth and metabolism. Similar to mammals, GH secretion in fish is under the control of hypothalamic factors. Besides, signals generated within the pituitary and/or from peripheral tissues/organs can also exert a feedback control on GH release by effects acting on both the hypothalamus and/or anterior pituitary. Among these feedback signals, the functional role of IGF is well conserved from fish to mammals. In contrast, the effects of steroids and thyroid hormones are more variable and appear to be species-specific. Recently, a novel intrapituitary feedback loop regulating GH release and GH gene expression has been identified in fish. This feedback loop has three functional components: (i) LH induction of GH release from somatotrophs, (ii) amplification of GH secretion by GH autoregulation in somatotrophs, and (iii) GH feedback inhibition of LH release from neighboring gonadotrophs. In this article, the mechanisms for feedback control of GH synthesis and secretion are reviewed and functional implications of this local feedback loop are discussed. This intrapituitary feedback loop may represent a new facet of pituitary research with potential applications in aquaculture and clinical studies.
Collapse
Affiliation(s)
- Anderson O L Wong
- Department of Zoology, University of Hong Kong, Pokfulam Road, Hong Kong, PR China.
| | | | | | | |
Collapse
|
41
|
Wilkinson RJ, Porter M, Woolcott H, Longland R, Carragher JF. Effects of aquaculture related stressors and nutritional restriction on circulating growth factors (GH, IGF-I and IGF-II) in Atlantic salmon and rainbow trout. Comp Biochem Physiol A Mol Integr Physiol 2006; 145:214-24. [PMID: 16861022 DOI: 10.1016/j.cbpa.2006.06.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2006] [Revised: 06/14/2006] [Accepted: 06/15/2006] [Indexed: 11/18/2022]
Abstract
The effects of aquaculture related stressors on circulating levels of GH, IGF-I and for the first time, IGF-II in Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) were investigated. Specifically, circulating growth factor levels were measured in four different experiments. Two 24 h confinement stressor procedures, (one with Atlantic salmon, the other with rainbow trout); following a hypo-osmotic stressor (freshwater bath) in salt water acclimated, adult, Atlantic salmon; and during a 22 day starvation and re-feeding protocol with juvenile Atlantic salmon. Handling and confinement resulted in significant decreases in circulating levels of all three growth factors in Atlantic salmon, and IGF-I and IGF-II (but not GH) in rainbow trout. A 2-3 h freshwater bath to remove gill parasites on a commercial Atlantic salmon aquaculture operation caused a significant decrease in circulating GH and IGF-I concentrations, but no significant change in IGF-II concentration, 2 days post bathing. Starvation for a period of 15 days in Atlantic salmon resulted in a significant increase in circulating GH levels and a significant decrease in circulating IGF-I and IGF-II. Re-feeding of starved fish for 7 days resulted in a significant decrease in GH to the concentration measured in continually fed fish, however re-feeding did not change plasma levels of IGF-I and IGF-II relative to continually starved fish. The results presented here confirm previously observed handling and confinement stressor induced effects on GH and IGF-I and, for the first time, on IGF-II in salmonids. Furthermore this study confirms the nutritional regulation of GH, IGF-I and IGF-II in juvenile Atlantic salmon.
Collapse
Affiliation(s)
- Ryan J Wilkinson
- School of Biological Sciences, Flinders University of South Australia, G.P.O. Box 2100, Adelaide, S.A. 5001, Australia.
| | | | | | | | | |
Collapse
|
42
|
Kasper RS, Shved N, Takahashi A, Reinecke M, Eppler E. A systematic immunohistochemical survey of the distribution patterns of GH, prolactin, somatolactin, beta-TSH, beta-FSH, beta-LH, ACTH, and alpha-MSH in the adenohypophysis of Oreochromis niloticus, the Nile tilapia. Cell Tissue Res 2006; 325:303-13. [PMID: 16552525 DOI: 10.1007/s00441-005-0119-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Accepted: 11/03/2005] [Indexed: 10/24/2022]
Abstract
Fish pituitary plays a central role in the control of growth, development, reproduction and adaptation to the environment. Several types of hormone-secreting adenohypophyseal cells have been characterised and localised in diverse teleost species. The results suggest a similar distribution pattern among the species investigated. However, most studies deal with a single hormone or hormone family. Thus, we studied adjacent sections of the pituitary of Oreochromis niloticus, the tilapia, by conventional staining and immunohistochemistry with specific antisera directed against growth hormone (GH), prolactin (PRL), somatolactin (SL), thyrotropin (beta-TSH), follicle-stimulating hormone (beta-FSH), luteinising hormone (beta-LH), adrenocorticotropic hormone (ACTH) and melanocyte-stimulating hormone (alpha-MSH). The pituitary was characterised by a close interdigitating neighbourhood of neurohypophysis (PN) and adenohypophysis. PRL-immunoreactive and ACTH-immunoreactive cells were detected in the rostral pars distalis. GH-immunoreactive cells were present in the proximal pars distalis (PPD). A small region of the PPD contained beta-TSH-immunoreactive cells, and beta-LH-immunoreactive cells covered approximately the remaining parts. Centrally, beta-FSH-immunoreactive cells were detected in the vicinity of the GH-containing cells. Some of these cells also displayed beta-LH immunoreactivity. The pars intermedia was characterised by branches of the PN surrounded by SL-containing and alpha-MSH-immunoreactive cells. The ACTH and alpha-MSH antisera were observed to cross-react with the respective antigens. This cross-reactivity was abolished by pre-absorption. We present a complete map of the distinct localisation sites for the classical pituitary hormones, thereby providing a solid basis for future research on teleost pituitary.
Collapse
Affiliation(s)
- Romano Silvio Kasper
- Division of Neuroendocrinology, Institute of Anatomy, University of Zürich, Winterthurerstrasse 190, Zürich, CH-8057, Switzerland
| | | | | | | | | |
Collapse
|
43
|
Li M, Greenaway J, Raine J, Petrik J, Hahnel A, Leatherland J. Growth hormone and insulin-like growth factor gene expression prior to the development of the pituitary gland in rainbow trout (Oncorhynchus mykiss) embryos reared at two temperatures. Comp Biochem Physiol A Mol Integr Physiol 2006; 143:514-22. [PMID: 16515871 DOI: 10.1016/j.cbpa.2006.01.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Revised: 01/14/2006] [Accepted: 01/16/2006] [Indexed: 11/16/2022]
Abstract
Real time RT-PCR was used to measure the changes in the rates of synthesis of mRNA encoding for growth hormone-1 (GH1) and -2 (GH2) and insulin-like growth factor-1 (IGF-1) and -2 (IGF-2), and whole embryo GH content was measured in early stage rainbow trout (Oncorhynchus mykiss) embryos reared at two incubation temperatures (8.5 and 6.0 degrees C). Particular attention was paid to the phase of embryo development that preceded the appearance of the pituitary gland. GH was present in zygotes, and there were no significant changes in whole embryo GH content of the two temperature treatment groups from fertilization (t0) until the time at which GH was detectable in the pituitary gland by immunostaining. The expression of the two GH genes decreased during the first 24 h post-fertilization, and then increased significantly by 17 dpf in embryos reared at both temperatures. There was a subsequent steep increase in the number of copies of GH1 and GH2 mRNA associated with the formation of the pituitary gland evident at 23 and 34 dpf in the 8.5 and 6.0 degrees C groups, respectively. The number of copies of mRNA encoding for IGF-1 and IGF-2 did not change during the first 24 h post-fertilization; however, there was a significant increase in the numbers of transcripts for both genes evident by 13 dpf in embryos reared at the two incubation temperatures. The differences in the timing of the increases in GH and IGF mRNA may suggest that IGF gene expression is not GH-dependent at that stage. Moreover, the increased expression of the GH genes prior to the formation of the pituitary gland suggests that tissues other than the pituitary are expressing these genes in early embryos. The pattern of changes in GH content was similar to the pattern of GH gene expression in embryos reared at the two incubation temperatures when the age of embryos was plotted using degree-days. There were no apparent compensatory responses in GH1, GH2, IGF-1 or IGF-2 gene expression related to altered growth rates. The number of copies of IGF-2 mRNA was higher than that of IGF-1 mRNA during the early developmental period; this is consistent with the hypothesis that IGF-2 predominates during embryonic development. A differential expression of GH2 and GH1 was also observed with the overall copy numbers of GH2 mRNA being consistently higher than those of GH1.
Collapse
Affiliation(s)
- Mao Li
- Department of Biomedical Sciences, University of Guelph, Guelph, Canada ON N1G 2W1.
| | | | | | | | | | | |
Collapse
|
44
|
Eppler E, Caelers A, Berishvili G, Reinecke M. The Advantage of Absolute Quantification in Comparative Hormone Research as Indicated by a Newly Established Real-Time RT-PCR: GH, IGF-I, and IGF-II Gene Expression in the Tilapia,Oreochromis niloticus. Ann N Y Acad Sci 2006; 1040:301-4. [PMID: 15891047 DOI: 10.1196/annals.1327.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have developed a real-time RT-PCR that absolutely quantifies the gene expression of hormones using the standard curve method. The method avoids cloning procedures by using primer extension to create templates containing a T7 promoter gene sequence. It is rapid since neither separate reverse transcriptions nor postamplification steps are necessary, and its low detection level (2 pg/mug total RNA) allows precise absolute quantification. Using the method, we have quantified the gene expression of GH, IGF-I, and IGF-II in the tilapia.
Collapse
Affiliation(s)
- Elisabeth Eppler
- Division of Neuroendocrinology, Institute of Anatomy, University of Zürich, Switzerland
| | | | | | | |
Collapse
|
45
|
Devlin RH, Sundström LF, Muir WM. Interface of biotechnology and ecology for environmental risk assessments of transgenic fish. Trends Biotechnol 2005; 24:89-97. [PMID: 16380181 DOI: 10.1016/j.tibtech.2005.12.008] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2005] [Revised: 11/08/2005] [Accepted: 12/09/2005] [Indexed: 10/25/2022]
Abstract
Genetically engineered fish with enhanced phenotypic traits have yet to be implemented into commercial applications. This is partly because of the difficulties in reliably predicting the ecological risk of transgenic fish should they escape into the wild. The ecological consequences of the phenotypic differences between transgenic and wild-type fish, as determined in the laboratory, can be uncertain because of genotype-by-environment effects (GXE). Additionally, we are limited in our ability to extrapolate simple phenotypes to the complex ecological interactions that occur in nature. Genetic background can also shape the phenotypic effects of transgenes, which, over time and among different wild populations, can make risk assessments a continuously evolving target. These uncertainties suggest that assessments of transgenic fish in contained facilities need to be conducted under as wide a range of conditions as possible, and that efficacious physical and biological containment strategies remain as crucial approaches to ensure the safe application of transgenic fish technology.
Collapse
Affiliation(s)
- Robert H Devlin
- Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, British Colombia, V7V 1N6, Canada.
| | | | | |
Collapse
|
46
|
Caelers A, Maclean N, Hwang G, Eppler E, Reinecke M. Expression of endogenous and exogenous growth hormone (GH) messenger (m) RNA in a GH-transgenic tilapia (Oreochromis niloticus). Transgenic Res 2005; 14:95-104. [PMID: 15865052 DOI: 10.1007/s11248-004-5791-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
We have previously produced transgenic fish from crosses between a wild-type female tilapia (Oreochromis niloticus) and a G transgenic male. This line of growth-enhanced tilapia carries a single copy of a chinook salmon (s) growth hormone (GH) gene spliced to an ocean pout antifreeze promoter (OPA-FPcsGH) co-ligated to a carp beta-actin/lacZ reporter gene construct, integrated into the tilapia genome. Because little is known about the expression sites of transgenes, we have characterised the gene expression patterns of sGH and tilapia (t)GH in transgenic tilapia using a newly established real-time PCR to measure the absolute mRNA amounts of both hormones. The sGH gene, which was expected to be expressed mainly in liver, was also found to be expressed in other organs, such as gills, heart, brain, skeletal muscle, kidney, spleen, intestine and testes. However, in pituitary no sGH mRNA but only tGH mRNA was found. Tilapia GH mRNA in wild-type pituitary amounted to 226 +/- 30 pg/microg total RNA but in transgenics only to 187 +/- 43 pg/microg total RNA. Liver exhibited the highest level of sGH mRNA (8.3 +/- 2.5 pg/microg total RNA) but the extrahepatic sites expressed considerable amounts of sGH mRNA ranging from 4.1 +/- 2.0 pg/microg total RNA in gills to 0.2 +/- 0.08 pg/microg total RNA in kidney. The widespread expression of the sGH gene is assumed to be due to the tissue specificity of the type III AFP gene promoter. It is assumed that our transgenic experiments, which in contrast to some other approaches caused no obvious organ abnormalities, mimick the GH expression during ontogeny. Because sGH mRNA is expressed both in liver and in extrahepatic sites it may not only promote secretion and release of liver-derived (endocrine) IGF-I leading to an overall growth enhancement but also stimulate IGF-I expression within the different organs in a paracrine/autocrine manner and, thus, further promote organ growth.
Collapse
Affiliation(s)
- Antje Caelers
- Division of Neuroendocrinology, Institute of Anatomy, University of Zürich, Zürich, Switzerland
| | | | | | | | | |
Collapse
|
47
|
Yada T, Muto K, Azuma T, Hyodo S, Schreck CB. Cortisol stimulates growth hormone gene expression in rainbow trout leucocytes in vitro. Gen Comp Endocrinol 2005; 142:248-55. [PMID: 15862570 DOI: 10.1016/j.ygcen.2005.01.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2004] [Revised: 01/11/2005] [Accepted: 01/13/2005] [Indexed: 11/27/2022]
Abstract
Extrapituitary expression of the growth hormone (GH) gene has been reported for the immune system of various vertebrates. In the rainbow trout (Oncorhynchus mykiss), GH mRNA could be detected in several lymphoid organs and leucocytes by reverse transcriptase-polymerase chain reaction (RT-PCR). To understand the control of GH expression in the fish immune system, mRNA levels for two distinct GH genes (GH1 and GH2) in trout leucocytes isolated from peripheral blood were quantified using a real-time PCR method. Both GH mRNAs could be detected in trout leucocytes, although their levels were extremely low compared to those in pituitary cells. The levels of GH2 mRNA in leucocytes were several times higher than those of GH1, while no difference was observed between GH1 and GH2 mRNA levels in the pituitary. Administration of dibutyryl cyclic AMP and cortisol produced a significant elevation of GH mRNA levels in trout leucocytes, although the levels were unchanged by T3. GH1 and GH2 mRNA levels showed similarities in responses to those factors. The effect of cortisol on GH mRNA appears biphasic; a dose-depending elevation of GH gene expression was observed in leucocytes treated with cortisol at below 200 nM, however, cortisol had no effect at 2000 nM. Cortisol-treated leucocytes showed no significant change in the mRNA level of beta-actin or proliferative activity during the experiments. Our results thus show that, at the low levels, GH gene expression in trout leucocytes is regulated by cortisol, which has been known as a regulatory factor of GH gene expression in pituitary cells, and suggest a physiological significance of paracrine GH produced in the fish immune system.
Collapse
Affiliation(s)
- Takashi Yada
- Freshwater Fisheries Research Division, National Research Institute of Fisheries Science, Nikko, Tochigi 321-1661, Japan.
| | | | | | | | | |
Collapse
|
48
|
Hostetler HA, Collodi P, Devlin RH, Muir WM. Improved Phytate Phosphorus Utilization by Japanese Medaka Transgenic for the Aspergillus niger Phytase Gene. Zebrafish 2005; 2:19-31. [PMID: 18248176 DOI: 10.1089/zeb.2005.2.19] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Heather A. Hostetler
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
- Present address: Department of Veterinary Physiology and Pharmacology, Texas A & M University, College Station, Texas
| | - Paul Collodi
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| | - Robert H. Devlin
- Canadian Oceans and Fisheries, Vancouver, British Columbia, Canada
| | - William M. Muir
- Department of Animal Sciences, Purdue University, West Lafayette, Indiana
| |
Collapse
|
49
|
McKay SJ, Trautner J, Smith MJ, Koop BF, Devlin RH. Evolution of duplicated growth hormone genes in autotetraploid salmonid fishes. Genome 2005; 47:714-23. [PMID: 15284876 DOI: 10.1139/g04-018] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A defining character of the piscine family Salmonidae is autotetraploidy resulting from a genome-doubling event some 25-100 million years ago. Initially, duplicated genes may have undergone concerted evolution and tetrasomic inheritance. Homeologous chromosomes eventually diverged and the resulting reduction in recombination and gene conversion between paralogous genes allowed the re-establishment of disomic inheritance. Among extant salmonine fishes (e.g. salmon, trout, char) the growth hormone (GH) gene is generally represented by two functional paralogs, GH1 and GH2. Sequence analyses of salmonid GH genes from species of subfamilies Coregoninae (whitefish, ciscos) and Salmoninae were used to examine the evolutionary history of the duplicated GH genes. Two divergent GH gene paralogs were also identified in Coregoninae, but they were not assignable to the GH1 and GH2 categories. The average sequence divergence between the coregonine GH genes was more than twofold lower than the corresponding divergence between the salmonine GH1 and GH2. Phylogenetic analysis of the coregonine GH paralogs did not resolve their relationship to the salmonine paralogs. These findings suggest that disomic inheritance of two GH genes was established by different mechanisms in these two subfamilies.
Collapse
Affiliation(s)
- S J McKay
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | | | | | | | | |
Collapse
|
50
|
Eales JG, Devlin R, Higgs DA, McLeese JM, Oakes JD, Plohman J. Thyroid function in growth-hormone-transgenic coho salmon (Oncorhynchus kisutch). CAN J ZOOL 2004. [DOI: 10.1139/z04-099] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We measured growth rate, plasma thyroxine (T4) and 3,5,3'-triiodothyronine (T3) concentrations, and liver and whole-brain T4 and T3 deiodination activities in yearling non-transgenic coho salmon, Oncorhynchus kisutch (Walbaum, 1792), fed a satiation ration (NTS) and in growth-hormone (GH)-transgenic salmon fed for 63 d with either a satiation ration (TS) or pair-fed the satiation ration consumed by NTS fish (TNT). Daily feed intake and specific growth rate for TS fish were significantly enhanced and approximately double those for TNT and NTS fish. There were no differences among groups in plasma T4 concentration or liver T4 outer-ring deiodination activity, but for both TS and TNT fish, plasma T3 concentrations were higher and liver T4 and T3 inner-ring deiodination activities were lower than for NTS fish. Whole-brain deiodination activities did not differ between TS and NTS fish. We conclude that the elevated plasma T3 concentrations of GH-transgenic salmon neither are driven by elevated plasma T4 concentrations nor are they the result of increased hepatic conversion of T4 to T3 by outer-ring deiodination. Instead they can be explained, at least in part, by reduced hepatic degradation of T3 to 3,3'-diiodothyronine by inner-ring deiodination. These changes in T4 and T3 metabolism are tightly linked to the GH-transgenic state and not to food intake or growth rate.
Collapse
|