共查询到20条相似文献,搜索用时 15 毫秒
1.
Inger Hilde Zahl Anders Kiessling Ole Bent Samuelsen Rolf Erik Olsen 《Fish physiology and biochemistry》2010,36(3):719-730
Stress in response to anesthesia with benzocaine, MS-222, metomidate and isoeugenol was studied in Atlantic salmon (Salmo salar), Atlantic halibut (Hippoglossus hippoglossus), and Atlantic cod (Gadus morhua) with no concomitant stress from handling or confinement in association with anesthesia or sampling. All of the anesthetics
tested induced a stress response in all species, displayed by a release of cortisol to the water. MS-222 anesthesia elicited
the highest cortisol release rates, reaching maximum levels 0.5 h post-exposure and returning to basal levels after 3–4 h.
Benzocaine anesthesia caused a bimodal response where the initial peak in cortisol release rate was followed by a second increase
lasting towards the end of the trial (6 h). This bimodality was more profound in Atlantic salmon than in Atlantic halibut
and Atlantic cod. Metomidate anesthesia induced the lowest release of cortisol of the agents tested in both Atlantic halibut
and Atlantic cod, but resulted in a bimodal response in Atlantic salmon where the initial increase in cortisol release was
followed by a larger increase peaking at 2–2.5 h post exposure before returning to basal levels after 5 h. The stress induced
in Atlantic salmon by isoeugenol anesthesia resembled that of MS-222, but did not reach the same elevated level. Overall,
the cortisol release was most profound in Atlantic salmon followed by Atlantic halibut and Atlantic cod. 相似文献
2.
Pablo A. Conejeros Carlos Calderón Daniela Gómez Luis Nilo Sergio H. Marshall 《Aquaculture International》2011,19(5):999-1005
As with any other intensively farmed animal species, the Atlantic salmon has been selectively bred and cross-bred to maximize
desirable traits. Selection tends to diminish genetic diversity in target populations, which among other negative effects
is hypothesized to decrease their capacity to confront a broad variety of pathogens. We have analyzed mitochondrial (mtDNA)
as well as major histocompatibility complex (MHC) DNA sequences from individuals collected from a single aquaculture cage
in southern Chile. Interestingly, only two mtDNA haplotypes were obtained; however, several different MH alleles were detected,
with divergence values that were compared with those of natural populations of salmonids. Thus, it seems evolutionary processes
responsible of keeping MH diversity in the wild managed to retain MH variability in farmed Atlantic salmon, maintaining high
immune diversity despite the generally lower levels of observed neutral genetic diversity. 相似文献
3.
Marianne Arnemo Arturas Kavaliauskis Adriana Magalhaes Santos Andresen Marta Bou Gerd Marit Berge Bente Ruyter Tor Gjøen 《Fish physiology and biochemistry》2017,43(4):1065-1080
The shortage of the n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the international markets has led to increasing substitution of fish oil by plant oils in Atlantic salmon (Salmo salar) feed and thereby reducing the EPA and DHA content in salmon. However, the minimum required levels of these fatty acids in fish diets for securing fish health are unknown. Fish were fed with 0, 1 or 2% EPA or DHA alone or in combination of both over a period, growing from 50 to 400 g. Primary head kidney leucocytes were isolated and stimulated with Toll-like receptor (TLR) ligands to determine if EPA and DHA deficiency can affect expression of important immune genes and eicosanoid production. Several genes related to viral immune response did not vary between groups. However, there was a tendency that the high-level EPA and DHA groups expressed lower levels of IL-1β in non-stimulated leucocytes. These leucocytes were also more responsive to the TLR ligands, inducing higher expression levels of IL-1β and Mx1 after stimulation. The levels of prostaglandin E2 and leukotriene B4 in serum and media from stimulated leucocytes were lower in both low and high EPA and DHA groups. In conclusion, leucocytes from low EPA and DHA groups seemed to be less responsive towards immunostimulants, like TLR ligands, indicating that low levels or absence of dietary EPA and DHA may have immunosuppressive effects. 相似文献
4.
Erik Vikingstad Eva Andersson Tom Johnny Hansen Birgitta Norberg Ian Mayer Sigurd Olav Stefansson Per Gunnar Fjelldal Geir Lasse Taranger 《Fish physiology and biochemistry》2016,42(3):895-907
Maturing male and female Atlantic salmon (Salmo salar L.) were held under three temperature regimes for 10 weeks between September and December: warm (constant 14–16 °C), ambient (decreasing from 11 to 5 °C), and cold (decreasing from 7 to 3 °C). Blood samples were analyzed for plasma steroid levels, and the fish were inspected for the presence of expressible milt (total volume and spermatocrit) and ovulation weekly. Samples of eggs were dry-fertilized with milt stripped from three males held at the same temperatures and incubated until the eyed stage. In females, levels of plasma testosterone (T) and 17β-oestradiol (E2) dropped as ovulation approached, concurrent with a rapid increase in levels of plasma 17α,20β-dihydroxy-4-pregnen-3-one (17,20β-P). In males, levels of T and 11-ketotestosterone (11-KT) peaked 2–3 weeks after the first appearance of expressible milt, while levels of 17,20β-P increased steadily and did not exhibit a definite peak. Exposure of females to cold water amplified and advanced the profiles of all three steroids compared with the ambient group, and increased the survival rates to the eyed egg stage. Cold water had no immediate effect on the male steroid profiles, but later, higher levels of 17,20β-P were evident compared with both the ambient controls and the warm water group, while the effects on 11-KT and T were more variable. Exposure to warm water completely inhibited both milt production and ovulation. Moreover, warm water modulated the steroid profiles of the males with lower 11-KT levels compared with ambient controls and lower 17,20β-P level compared with cold-water-treated males. In females, warm water resulted in total inhibition of the peri-ovulatory peak in 17,20β-P and prevented the normal decline of T and E2 levels associated with ovulation. The findings of the present study are highly relevant for broodstock management in aquaculture, as well in understanding the impact of climate change/temperature variability on wild salmon spawning. 相似文献
5.
6.
The productivity and welfare benefits of sustained swimming in fish are well documented, but are not yet exploited in commercial
aquaculture. We report here on a study designed to test the feasibility of inducing sustained exercise in Atlantic salmon
(Salmo salar L.) using a novel lighting device that provides an apparently moving light pattern. It was found that such a device could
induce sustained swimming in Atlantic salmon held in tanks and that a centrally placed (inner ring) light system was far more
effective in this context than one in which lights were placed on the outer wall of tanks. The central configuration was associated
with enhanced rates of growth, feed conversion and reduced levels of plasma cortisol. Such developments in fish swimming technologies
may assist the sustainability of finfish aquaculture through promotion of sustained exercise leading to improved productivity
and welfare. 相似文献
7.
Dorafshan S Kalbassi MR Pourkazemi M Amiri BM Karimi SS 《Fish physiology and biochemistry》2008,34(3):195-200
The aim of this study was a comparison of key haematological features of diploid (2n) and triploid (3n) Caspian salmon (Salmo trutta caspius). Morphometric indices of erythrocytes were determined on blood smears by light microscopy. Triploidy significantly (P < 0.001) increased all morphometric indices measured in the erythrocytes including cell size, cell surface area, and cell
volume. The increase in cell size was larger for the major (27%) axis than for the minor (22%) axis, thus making erythrocytes
of 3n Caspian salmon more ellipsoidal. The estimated increase in erythrocyte nuclear volume (87%) was bigger than the theoretical
expected 50% increase. Haematological indices were measured manually by hemocytometry. Triploids had lower numbers of red
blood cells (RBC: 1,120,000 cells/mL in 2n vs. 700,000 cells/mL in 3n; P < 0.001) but they were larger in size (mean erythrocytic volume [MEV]: 363.1 nm3 in 2n vs. 483.3 nm3 in 3n; P < 0.001). The decrease in RBC number was not compensated by the increase in MEV and, thus, triploidy affected the haematocrit
(Hct: 38.8% in 2n vs. 33.06% in 3n; P < 0.05). Total blood hemoglobin concentration was lower in triploid fish (Hb: 9.9 g/dL in 2n vs. 8.9 g/dL in 3n; P < 0.05). In contrast, mean erythrocytic hemoglobin (MEH: 95 μg in 2n vs. 133.2 μg in 3n; P < 0.001) was higher for 3n Caspian salmon as a result of their larger erythrocytes, although MEH concentration (MEHC: 0.26 g/dL
in 2n vs. 0.27 g/dL in 3n) did not significantly differ (P > 0.05). White blood cell (WBC) counts (lymphocytes and neutrophiles) were measured and WBC/RBC ratios were calculated. There
were no significant differences in WBC (15,710 cells/mL in 2n vs. 12,683 cells/mL in 3n; P > 0.05), lymphocytes, and neutrophils as %WBC as well as WBC/RBC ratios between two ploidy levels (P > 0.05). Triploid Caspian salmon showed higher erythrocyte abnormalities such as ‘twisted’, ‘tailed’, and ‘anucleated’ cells
as well as high portions of immature RBC in blood smears in comparison with diploids (P < 0.001). 相似文献
8.
Hiam Elabd Han-Ping Wang Adel Shaheen Hong Yao Amany Abbass 《Fish physiology and biochemistry》2016,42(3):955-966
This study was designed to assess the potential effects of Astragalus membranaceus (AM) on the growth performance and antioxidative stress response in bluegill sunfish (Lepomis macrochirus) exposed to challenging cold water temperature conditions. In this regard, fish with an average weight of 43 ± 1 g were divided into four groups and fed daily with an AM-free diet (control), and 1.5, 3, and 4.5 % (w/w) AM-incorporated diets for an 8-week period. Oxidative stress response, biochemical, and growth parameters were measured, and subgroups of fish were exposed to the outside challenging cold pond water temperature (1.6–9.9 °C) with an average of 7.0 ± 0.1 °C beyond the optimal temperature. The results showed that incorporating AM in the diet significantly improved growth performance parameters (body mass gain, specific growth rate, length, condition factor, and feed conversion ratio) and biochemicals (aspartate aminotransferase and alanine transaminase activities, and glucose and cortisol concentrations). In addition, markedly up-regulated superoxide dismutase, glutathione peroxidase, and catalase activities were observed in AM-treated fish groups over the control. Conclusively, feeding AM diets significantly increased (P < 0.05) growth performance and antioxidative stress profiles throughout the entire experiment, and this increase was much more pronounced at 8 weeks after the water temperature began to rise, which can be related to the nature of Bluegill fish as it is known to be a warm water fish. These findings are considered to be of great importance for sustainable aquaculture. 相似文献
9.
Pedersen ME Takle H Ytteborg E Veiseth-Kent E Enersen G Færgestad E Baeverfjord G Hannesson KO 《Fish physiology and biochemistry》2011,37(4):821-831
We have previously characterized the development of vertebral fusions induced by elevated water temperature in Atlantic salmon.
Molecular markers of bone and cartilage development together with histology were used to understand the complex pathology
and mechanism in the development of this spinal malformation. In this study, we wanted to use proteomics, a non-hypothetical
approach to screen for possible new markers involved in the fusion process. Proteins extracted from non-deformed and fused
vertebrae of Atlantic salmon were therefore compared by two-dimensional electrophoresis (2DE) and MALDI-TOF analysis. Data
analysis of protein spots in the 2DE gels demonstrated matrilin-1, also named cartilage matrix protein, to be the most highly
up-regulated protein in fused compared with non-deformed vertebrae. Furthermore, real-time PCR analysis showed strong up-regulation
of matrilin-1 mRNA in fused vertebrae. Immunohistochemistry demonstrated induced matrilin-1 expression in trans-differentiating
cells undergoing a metaplastic shift toward chondrocytes in fusing vertebrae, whereas abundant expression was demonstrated
in cartilaginous tissue and chordocytes of both non-deformed and fused vertebrae. These results identifies matrilin-1 as a
new interesting candidate in the fusion process, and ratify the use of proteomic as a valuable technique to screen for markers
involved in vertebral pathogenesis. 相似文献
10.
Ana Teresa Gonçalves Masashi Maita Kunihiko Futami Masato Endo Takayuki Katagiri 《Fisheries Science》2011,77(4):633-642
To test the effects of probiotic bacteria against crowding stress, juvenile Nile tilapia Oreochromis niloticus were fed commercial feed supplemented with 1 × 1010 cfu/g pellets of Lactobacillus rhamnosus for 3 weeks. The fish were confined and subjected to crowding for 7 and 14 days after which their physiological condition
was investigated. The administration of probiotic prophylaxis improved growth performance even in the stressed fish. After
7 days of stress exposure, fish receiving probiotic-supplemented feed showed proactive behavior and coping responses to the
stressor, as evidenced by elevated plasma glucose levels and osmolality, stabilized plasma electrolytes, and a higher RNA:DNA
ratio. Fish stressed for 7 days and fed normal commercial diet showed impairment of plasma electrolytes; after 14 days, the
plasma osmolality, electrolytes, glucose, and RNA:DNA ratio decreased, indicating physiological maladaptation to the stressor.
The growth rate was also found to be reduced, suggesting that energy demand exceeded the energy available from metabolism
and dietary uptake. This latter effect was not observed in fish fed the probiotic-supplemented diet. The results suggest that
probiotic bacteria prophylaxis may increase energy availability for metabolic support of the crowding stress response and
improve the stress coping capacity of fish. 相似文献
11.
Atlantic salmon (Salmo salar) was grown in sea cages from 700 g to a market size of 3.2 kg on diets containing either 29% Peruvian high polyunsaturated fatty acids (PUFA) fish oil (FO) or 29% soybean oil (SO) as oil source. Chemical analyses and a triangular consumer test were performed on fresh muscle, while colour, texture and liquid holding capacity (LHC) analyses were performed on both fresh muscle, frozen muscle (stored for 3 months) and smoked salmon. The growth and chemical composition of flesh was not affected by the dietary treatment. The muscle fatty acid (FA) profile was reflected by the dietary oil source, and the amount of malondialdehyde (MDA) was threefold higher in the salmon fed FO than SO. Muscle pigment concentration was significantly different (p < 0.01) with 7.9 mg kg–1 for FO and 5.6 mg kg–1 for SO fed salmon, respectively. This result was also significantly (p < 0.05) reflected in the difference between the instrumentally measured colour of fresh, frozen and smoked muscle, and visual impressions of fresh and frozen muscle. Gaping, texture and liquid holding capacity was not affected by the dietary treatment, and the consumer panel did not detect any differences between the dietary groups. SO can be used as a dietary oil source in the grow-out phase of salmon production without sacrificing product quality in terms of texture, liquid holding capacity and consumer preference. However, a total substitution of high PUFA fish oil by SO in diets for salmon grown to market size, affects muscle colour and the FA profile significantly. (p < 0.05). 相似文献
12.
Triploid hybrids between female rainbow trout (Oncorhynchus mykiss Walbaum) and male brown trout (Salmo trutta L.) were tested for farming performances, with reference to parental species. The main drawback of hybrids lay in embryonic
and larval mortalities, amounting to 60% on average, and displaying a large variability between spawns. Further survival was
inferior to that of diploid, but similar to that of triploid rainbow trout. Hybrid body weight was intermediate between weights
of rainbow and brown trout of the same age, mainly as a consequence of differences in precocious growth. Analysis of relative
growth rates from 6 to 18 months showed that hybrids were surpassed by rainbow controls in common rearing, but not in separate
rearing. Hybrid behaviour was similar to that of rainbow trout. These results are discussed in the scope of providing fisheries
managers with original and sterile game fishes.
An erratum to this article can be found at . 相似文献
13.
T. Kristensen B. O. Rosseland A. Kiessling B. Djordevic J. C. Massabau 《Fish physiology and biochemistry》2010,36(4):1087-1095
Regulation of arterial partial pressure of O2 (PaO2) in Atlantic salmon (Salmo salar) was investigated during resting conditions in normoxic and hyperoxic water. Dorsal aorta cannulated adult Atlantic salmon
(1.2–1.6 kg, n = 8) were exposed to 2 week sequential periods of normoxia [16.7 ± 1.1 kPa (mean ± SD)] and hyperoxia (34.1 ± 4.9 kPa) in
individual tanks containing seawater (33.7 ± 0.2 ppt) at stable temperature conditions (8.7 ± 0.7°C) and a light regime of
L:D = 12:12. Tank design and sampling procedures were optimized to provide suitable shelter and current for the fish, and
to allow repeated, undisturbed sampling of blood from free-swimming fish. Fish were sampled regularly through the experimental
period. PwO2, PaO2, blood ion composition (Na+, K+, Cl−), acid–base status (pH, PCO2, HCO3
−), haematocrit and glucose were measured. The most frequently observed PaO2 values were in the range of 60–80% of PwO2, both during normoxia and hyperoxia, and PaO2 values were significantly lower during normoxia than during hyperoxia. Blood pH, PCO2 and HCO3
− were significantly elevated during hyperoxia, while, Na+, Cl− and Hct were significantly lower. K+ and glucose showed no significant differences. This study demonstrates a lack PaO2 regulation in Atlantic salmon to low partial pressures, in contrast to previous reports for many aquatic gill breathing animals.
Both during normoxia and hyperoxia, PaO2 reflects PwO2, and alterations in external PO2 consequently result in proportional arterial PO2 changes. Physiological adaptation to hyperoxia, as illustrated by changes in several blood parameters, does not include down-regulation
of PaO2 in Atlantic salmon. The lack of PaO2 regulation may make Atlantic salmon vulnerable to the oxidative stress caused by increased free radical formation in hyperoxic
conditions. 相似文献
14.
Silje Bratland Lars Helge Stien Victoria A. Braithwaite Jon-Erik Juell Ole Folkedal Jonatan Nilsson Frode Oppedal Jan Erik Fosseidengen Tore S. Kristiansen 《Aquaculture International》2010,18(6):991-1001
In this study, we demonstrate how an event that is initially frightening to Atlantic salmon is turned to a positive stimulus
through habituation and associative learning. The study was carried out in four commercial sized tanks (5 m3) with near industry densities (>550 fish, 16 kg m−3), using a delay conditioning procedure with an aversive flashing light as the conditioned stimulus and food reward as the
unconditioned stimulus. By using video image analysis of the distribution of the fish in the tanks, the changes in behaviour
from trial to trial could be documented in great detail. The current study documents the change in behaviour across the individual
conditioning trials, clearly showing the step-by-step nature of the transition. The salmon needed more than 26 trials to become
fully habituated to the flashing light but showed clear anticipatory behaviour already after about 19 trials. This demonstrates
that the learning process is a combination of habituation and associative learning. 相似文献
15.
We analysed the genetic diversity of Melicertus kerathurus (Penaeidae), a commercially valuable penaeid shrimp that is distributed in the Mediterranean Sea and eastern Atlantic Ocean.
We examined the polymorphism of a 494 bp DNA segment of the mitochondrial COI region in 173 individuals, sampled in nine Mediterranean
and two Atlantic samples, covering the whole range of the species from the tropical waters of the Gulf of Guinea to the eastern
part of the Mediterranean Sea. The mean nucleotide and haplotype diversities were π = 0.00275 and h = 0.718, respectively, for the global data set, with the highest values occurring in the African samples and the lowest in
the Adriatic Sea. A clear sample differentiation was found (F
st = 0.194), but this did not reflect a geographical pattern and there were only faint traces of an Atlantic–Mediterranean subdivision.
Mismatch analysis and a high significant negative value of Tajima’s D suggested that M. kerathurus is not at mutation drift-equilibrium, but underwent a recent expansion after a period of low effective sample size. A postglacial
recolonisation of the Mediterranean from an Atlantic refuge could be hypothesised based on these data. 相似文献
16.
Krisna Rungruangsak-Torrissen Jan Sunde Arne Erik Berg Ulla Nordgarden Per Gunnar Fjelldal Frode Oppedal 《Fish physiology and biochemistry》2009,35(2):255-272
This study comprised the results of three different seawater trials using unique combination of techniques to study protease
digestive efficiency and growth performance quality to illustrate the effects of light regimes and vaccine types in Atlantic
salmon (Salmo salar L.). Fish with higher growth had higher trypsin (T) and chymotrypsin (C) specific activities with higher T/C ratio or slope
T/C ratio [calculated from the regression between trypsin (y) and chymotrypsin (x) specific activities] in the pyloric caeca. The T/C ratios indicated fish growth rates over a period of 1–2 months, while
the slope T/C ratios indicated fish growth rates at sampling. Adaptation period for adjustment to the new environment of continuous
light was 70 days, indicated by the differences in trypsin specific activities and the crossing of slope T/C ratio regressions
following with the changes in growth rate directions between the control and the treated group. Vaccine types affected fish
vertebral growth, and additional continuous light enhanced the impact of vaccines on fish growth during springtime, indicated
by differences in slope T/C ratios. Continuous light stimulated fish growth during winter to spring, when the natural day
length was short, without significantly changing white muscle and oocyte qualities in the fish of about 500 g, except for
significantly increased white muscle RNA concentration. Continuous light also reduced fish growth rate later during summer,
when the natural day length was long, by precedently decreasing the T/C ratio in late spring. Interestingly, plasma levels
of free lysine related to tryptic digestion were correlated with trypsin specific activity levels. Continuous light caused
higher levels of most free amino acids (FAA) involved in nitrogen metabolism, higher incorporation of essential FAA for protein
synthesis, and higher protein turnover rate (free hydroxyproline levels) in both plasma and white muscle. However, continuous
light did not affect higher protein content, intracellular buffering capacity and RNA levels in the white muscle of the fish
of about 1 kg, probably due to limitation of FAA available for protein synthesis. It is therefore suggested that enhancing
fish growth by continuous light stimulation should be accompanied by increasing availability or content of dietary protein
(and probably minerals), which in turn would improve the quality of fish growth performance through increasing fillet protein
concentration, strengthening vertebral growth, and delaying oocyte development. 相似文献
17.
Shoichiro Yamamoto Satoshi Kitano Hiroyuki Sakano Masayuki Yagyu 《Fisheries Science》2010,76(2):275-280
Brown trout Salmo trutta were first introduced into Japan in 1892, and they currently naturally reproduce in several rivers in Honshu and Hokkaido,
Japan. Although negative impacts of brown trout introductions on native salmonid fishes have been documented in some Hokkaido
rivers, studies of ecological interactions between brown trout and native salmonid fishes on Honshu are limited. In this study,
we describe the longitudinal distribution patterns of introduced brown trout, white-spotted charr Salvelinus leucomaenis and masu salmon Oncorhynchus masou in a 4 km stretch of a stream in central Honshu. Underwater observations were conducted in all pools within upstream, middle
and downstream sections (190–400 m in length) of this stretch in order to estimate the densities of these species. Only white-spotted
charr was observed in the upstream section, while brown trout and masu salmon were observed in the middle and downstream sections.
Masu salmon densities, however, were much lower than brown trout densities. In the downstream section, white-spotted charr
was absent. These results are consistent with results from previous studies of Hokkaido rivers, where it was found that white-spotted
charr in low-gradient areas tend to be displaced by brown trout. 相似文献
18.
As the supply of marine fish oil is becoming a limiting factor in the production of Atlantic salmon (Salmo salar), new diets and alternative sources of energy are being tested. Plant oils are natural potential candidates to replace fish oil, but the different levels of essential polyunsaturated fatty acids may influence the health and growth of salmon. In this study, we have investigated the resistance to transport stress and bacterial infection, phagocytic activity in head kidney macrophages and eicosanoid metabolism in salmon fed three different diets. In high-energy fishmeal based diets, 50% and 100% of the supplementary fish oil (FO) was replaced with soybean oil (SO). The three dietary groups were fed for 950 day-degrees at 5 °C (27 weeks) and 12 °C (11 weeks) before challenging the fish with Aeromonas salmonicida, analyzing the lipid composition of head kidney and examining macrophage function in vivo and in vitro. Dietary fatty acids affected the lipid composition of the kidney. The level of eicosanoid precursor’s 20:4n-6 and 20:3n-6 were 3 and 7-fold higher in the 100% SO group compared with the FO group. The total fraction of n-3 lipids in kidney was 19% in the SO group, compared to 16% and 12% in the 50% or 100% SO groups, respectively. However, the production of leucotriene B4 (LTB) and prostaglandin E2 (PGE) immunoreactive materiel from exogenously added arachidonic acid in head kidney macrophages was only affected by the composite diet (increased) at 5 °C. In addition, the phagocytic activity of kidney macrophages in vivo and in vitro was not affected by diet. No effect of diet was observed on transport stress or susceptibility to a bacterial infection with Aeromonas salmonicida. Atlantic salmon therefore seems to tolerate a diet solely based on soybean oil as lipid source, without any detrimental effects on growth, health and immune functions. 相似文献
19.
Two isoforms of the full-length cDNA of the growth hormone receptor (GHR) of the Atlantic salmon (Salmo salar; ss) were cloned by a PCR approach using RACE. Respectively, the cDNA sequences of ssGHR isoforms 1 and 2 are 2654 and 2608 nucleotides long, with 1782 and 1773 nucleotide ORFs. The resulting coded proteins
are 594 and 590 aa long, with 19 and 20 aa signal peptides. The two isoforms share 86% protein and 87% cDNA sequence similarity.
Isoform 1 is most similar to other salmonid GHR isoforms 1 while isoform 2 is most similar to salmonid GHR isoforms 2 (93–95%).
Similarity with other teleost species was lower (37–44%). The bioactivity of the cloned ssGHR was tested by transfecting the ssGHR isoform 1 cDNA into CHO-K1 hamster cells, incubating with recombinant salmon GH (sGH) or native ovine prolactin (oPRL),
and measuring cell proliferation by the MTT assay. The ssGHR-transfected cells significantly increased proliferation when stimulated by sGH at all concentrations. oPRL stimulated
ssGHR-transfected cells at higher concentrations due to receptor cross reaction. ssGHR isoforms 1 and 2 contain a single transmembrane domain and the typical conserved motifs found in other teleost GHRs, including
four paired cysteine residues and five potential N-glycosylation sites in the extracellular domain, Box I and Box II, as well as seven potential tyrosine phosphorylation sites
in the intracellular domain. However, in salmonids, these motifs differ from those of other teleosts, and could be responsible
for differentiated hormone binding, signal transduction and response. 相似文献
20.
Tram T. Vuong Sissel B. Rønning Svein O. Kolset Mona E. Pedersen 《Fish physiology and biochemistry》2017,43(1):19-25
Post mortem storage is a necessary process for removal of pin bones without destruction of fillets, thereby avoiding volume and economic loss. However, the enzymes involved in loosening pin bones during storage have not been studied to a great extent. In this study, the activities and localization of MMPs in the connective tissue (CT) of pin bones dissected from fillet of salmon and cod were investigated. Interestingly, the enzyme activity profile in these two species was different during post mortem storage of fish fillets. Adding MMP inhibitor (GM6001) and serine protease inhibitor (Pefabloc) revealed different effects in the two species, suggesting different regulations in salmon and cod. In situ zymography with the same inhibitors verified MMP and serine protease activity in CT close to pin bone at early post mortem (6 h) in salmon. However, MMP inhibition was not evident in cod in this area at that time point. Immunohistochemistry further revealed MMP9 and MMP13 were located more to the outer rim of CT, facing the pin bone and adipose tissue, while MMP7 was more randomly distributed within CT in salmon. In contrast, all these three MMPs were randomly distributed in CT in cod. In summary, our study reveals different MMP enzyme profiles in salmon and cod in the pin bone area, influenced by serine proteases, and suggests that MMPs and serine proteases must be taken in consideration when studying the conditions for early pin bone removal. 相似文献