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1.
Insertion of a growth hormone (GH) transgene in coho salmon results in accelerated growth, and increased feeding and metabolic rates. Whether other physiological systems within the fish are adjusted to this accelerated growth has not been well explored. We examined the effects of a GH transgene and feeding level on the antioxidant glutathione and its associated enzymes in various tissues of coho salmon. When transgenic and control salmon were fed to satiation, transgenic fish had increased tissue glutathione, increased hepatic glutathione reductase activity, decreased hepatic activity of the glutathione synthesis enzyme γ-glutamylcysteine synthetase, and increased intestinal activity of the glutathione catabolic enzyme γ-glutamyltranspeptidase. However, these differences were mostly abolished by ration restriction and fasting, indicating that upregulation of the glutathione antioxidant system was due to accelerated growth, and not to intrinsic effects of the transgene. Increased food intake and ability to digest potential dietary glutathione, and not increased activity of glutathione synthesis enzymes, likely contributed to the higher levels of glutathione in transgenic fish. Components of the glutathione antioxidant system are likely upregulated to combat potentially higher reactive oxygen species production from increased metabolic rates in GH transgenic salmon.  相似文献   

2.
We surveyed microsatellite variation from 22 spawning populations of coho salmon (Oncorhynchus kisutch) from the Oregon Coast to help identify populations for conservation planning. All of our samples were temporally replicated, with most samples obtained in 2000 and 2001. We had three goals: (1) to confirm the status of populations identified on the basis of spawning location and life history; (2) to estimate effective population sizes and migration rates in order to determine demographic independence at different spatial scales; and (3) to determine if releases of Washington hatchery coho salmon in the 1980's into Oregon Coast streams resulted in measurable introgression into nearby wild Oregon Coast coho populations. For the last question, our study included a hatchery broodstock sample from 1985, after the Puget Sound introduction, and a 1975 sample taken from the same area prior to the introduction. Our results generally supported previously hypothesized population structure. Most importantly, we found unique lake-rearing groups identified on the basis of a common life-history type were genetically related. Estimates of immigrant fraction using several different methods also generally supported previously identified populations. Estimates of effective population size were highly correlated with estimates of spawning abundance. The 1985 hatchery sample was genetically similar to contemporary Washington samples, and the contemporary Oregon Coast samples were similar to the 1975 Oregon Coast sample, suggesting that introductions of Washington coho salmon did not result in large scale introgression into Oregon populations.  相似文献   

3.
The young of the year mykiss Parasalmo mykiss and coho salmon Oncorhynchus kisutch which perform downstream migration and which stay in the coastal zone during the period of primary dispersion represent different phenotypic groups. They differ in weight, length, and lipid status. Such differentiation is a factor controlling the formation of intrapopulation diversity and of the life strategy of fish. It may determine the timing of smoltification in the future and, further on, of the return for spawning. There were found some analogies and differences in characteristics of lipid metabolism in the investigated species. The content of total lipids decreases by autumn in underyearlings of both species. Furthermore, changes in the content of particular lipid fractions are multidirectional and various scaled, seemingly being related to physiological preparation for the wintering.  相似文献   

4.
Resting spores of Ichthyophonus hoferi (50–230 μm in diameter) were found in the kidney, heart, liver, skeletalal muscles, exocrine pancreas, and connective and fatty tissues of young coho salmon Oncorhynchus kisutch from the Vilyuisky fish hatchery. In 10% of the fish, there were granulomas and giant cells in these organs. This is the first report of Ichthyophonus infection in Kamchatka.  相似文献   

5.
We investigated habitat use by juvenile Chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch) to identify environmental characteristics that may define their optimal marine habitat. We utilized physical and biological data from four cruises in the northern California Current system from Newport, Oregon, to Crescent City, California, in June and August 2000 and 2002. A non-parametric statistical method was used to analyze and select environmental parameters that best defined ocean habitat for each species. Regression trees were generated for all cruises combined to select the most important habitat variables. Chlorophyll a concentration best defined habitat of yearling Chinook salmon, while decapod larvae, salinity, and neuston biovolume defined habitat of yearling coho salmon. Using criteria from the regression tree analysis, GIS maps were produced to show that the habitat of yearling Chinook salmon was widespread over the continental shelf and the habitat of yearling coho salmon was variable and mainly north of Cape Blanco.  相似文献   

6.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

7.
Otoliths, or ‘ear stones’, are calcium carbonate structures found in all vertebrates. In teleosts, they have a number of sensory functions, including hearing. Daily growth increments of these structures have permitted advanced age and population studies of teleosts. Whereas ‘normal’ otoliths are composed of crystals imbedded within a protein matrix as aragonite, a ‘crystalline’ form of calcium carbonate termed vaterite is also found. A review of the otolith literature demonstrates a significant level of understanding of the structure and function of otoliths, but the cause for crystalline otolith structure remains speculative. Pairs of otoliths from hatchery and wild juvenile and adult coho salmon (Oncorhynchus kisutch) were examined visually for determination of otolith microstructure type. The vateritic or crystalline otoliths were found in much higher percentages in juvenile hatchery-reared coho salmon than in juvenile wild coho salmon, supporting previous studies. There did not seem to be any negative impact on size or survival. There was also no correlation between crystalline otoliths and premature maturation in coho males. A preliminary study of adult coho salmon returning to Big Qualicum and Chilliwack hatcheries showed even higher ratios of vateritic otoliths than observed in juveniles.  相似文献   

8.

Key message

Arabidopsis det1 mutants exhibit salt and osmotic stress resistant germination. This phenotype requires HY5, ABF1, ABF3, and ABF4.

Abstract

While DE-ETIOLATED 1 (DET1) is well known as a negative regulator of light development, here we describe how det1 mutants also exhibit altered responses to salt and osmotic stress, specifically salt and mannitol resistant germination. LONG HYPOCOTYL 5 (HY5) positively regulates both light and abscisic acid (ABA) signalling. We found that hy5 suppressed the det1 salt and mannitol resistant germination phenotype, thus, det1 stress resistant germination requires HY5. We then queried publically available microarray datasets to identify genes downstream of HY5 that were differentially expressed in det1 mutants. Our analysis revealed that ABA regulated genes, including ABA RESPONSIVE ELEMENT BINDING FACTOR 3 (ABF3), are downregulated in det1 seedlings. We found that ABF3 is induced by salt in wildtype seeds, while homologues ABF4 and ABF1 are repressed, and all three genes are underexpressed in det1 seeds. We then investigated the role of ABF3, ABF4, and ABF1 in det1 phenotypes. Double mutant analysis showed that abf3, abf4, and abf1 all suppress the det1 salt/osmotic stress resistant germination phenotype. In addition, abf1 suppressed det1 rapid water loss and open stomata phenotypes. Thus interactions between ABF genes contribute to det1 salt/osmotic stress response phenotypes.
  相似文献   

9.
A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.  相似文献   

10.
Summary  Eleven species comprising the Madagascan genus Vaughania are subsumed within the large pantropical genus Indigofera. Six new combinations are made; the remaining species were originally described in Indigofera.  相似文献   

11.
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.  相似文献   

12.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

13.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

14.
Germplasm conservation of Podophyllum peltatum L. was attempted by using synthetic seed technology and media supplemented with osmotic agents. Excised buds from in vitro cultures were encapsulated in calcium alginate beads and cultured on different substrates then stored at 5, 10, and 25°C for up to 8 mo. Survival and vigor in re-growth were the parameters used to evaluate the germplasm storage conditions. Vigor in re-growth was measured by number of buds induced after storage, which was achieved on a substrate containing water solidified with 1% w/v agar under 10°C. In vitro storage of shoot cultures was also evaluated by supplementing osmotic agents, mannitol, or sorbitol to the media. Such treatment had a negative impact on post-storage re-growth (at 25°C), even though the inclusion of 2% w/v sorbitol and mannitol each to the media increased plantlet survival during 10°C storage treatment. A deleterious effect was noticed among cultures in re-growth when higher concentrations of these supplements were added to the media. Genetic stability was assessed following 8 mo of storage using a PCR-based multilocus DNA fingerprinting technique, amplified fragment-length polymorphism. No differences in the DNA fragment patterns were observed using eight primer combinations in stored clones. However, a polymorphic band was noticed in the accession that served as explant source, suggesting that the mutation has occurred prior to this study perhaps during the 9 years of in vitro cultivation.  相似文献   

15.
A peptide antibiotic, gramicidin A, was covalently bound to cystamine self-assembled monolayers on gold surfaces. Each step of the surface functionalization was characterized by polarization modulation infrared reflection absorption spectroscopy and X-ray photoelectron spectroscopy. The antimicrobial activity of the anchored gramicidin was tested against three Gram-positive bacteria (Listeria ivanovii, Enterococcus faecalis, and Staphylococcus aureus), the Gram-negative bacterium Escherichia coli and the yeast Candida albicans. The results revealed that the adsorbed gramicidin reduced, from 60% for E. coli to 90% for C. albicans, the number of culturable microorganisms attached to the surface. The activity was proven to be persistent overtime, up to 6 months after the first use. The bacteria attached to the functionalized surfaces were permeabilized as shown by confocal microscopy. Taken together, these results indicate a bacteriostatic mode of action of the immobilized peptide. Finally, using green fluorescent protein-expressing bacteria, it was shown that the development of a bacterial biofilm was delayed on peptide-grafted surfaces for at least 24 h.  相似文献   

16.
17.
Seol E  Jung Y  Lee J  Cho C  Kim T  Rhee Y  Lee S 《Plant cell reports》2008,27(7):1197-1206
Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.  相似文献   

18.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

19.
20.
The earlier identified gene RAD31 was mapped on the right arm of chromosome II in the region of gene MEC1 localization. Epistatic analysis demonstrated that the rad31 mutation is an allele of the MEC1 gene, which allows further designation of the rad31 mutation as mec1-212. Mutation mec1-212, similar to deletion alleles of this gene, causes sensitivity to hydroxyurea, disturbs the check-point function, and suppresses UV-induced mutagenesis. However, this mutation significantly increases the frequency of spontaneous canavanine-resistance mutations induced by disturbances in correcting errors of DNA replication and repair, which distinguishes it from all identified alleles of gene MEC1.  相似文献   

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