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William R. Brignon Martin M. Pike Lars O. E. Ebbesson Howard A. Schaller James T. Peterson Carl B. Schreck 《Environmental Biology of Fishes》2018,101(3):383-401
Animals reared in barren captive environments exhibit different developmental trajectories and behaviors than wild counterparts. Hence, the captive phenotypes may influence the success of reintroduction and recovery programs for threatened and endangered species. We collected wild bull trout embryos from the Metolius River Basin, Oregon and reared them in differing environments to better understand how captivity affects the bull trout Salvelinus confluentus phenotype. We compared the boldness and prey acquisition behaviors and development of the brain and eye lens of bull trout reared in conventional barren and more structurally complex captive environments with that of wild fish. Wild fish and captive reared fish from complex habitats exhibited a greater level of boldness and prey acquisition ability, than fish reared in conventional captive environments. In addition, the eye lens of conventionally reared bull trout was larger than complex reared captive fish or same age wild fish. Interestingly, we detected wild fish had a smaller relative cerebellum than either captive reared treatment. Our results suggest that rearing fish in more complex captive environments can create a more wild-like phenotype than conventional rearing practices. A better understanding of the effects of captivity on the development and behavior of bull trout can inform rearing and reintroduction programs though prediction of the performance of released individuals. 相似文献
95.
Irene Zubiri Vittoria Lombardi Michael Bremang Vikram Mitra Giovanni Nardo Rocco Adiutori Ching-Hua Lu Emanuela Leoni Ping Yip Ozlem Yildiz Malcolm Ward Linda Greensmith Caterina Bendotti Ian Pike Andrea Malaspina 《Molecular neurodegeneration》2018,13(1):60
Background
It is unclear to what extent pre-clinical studies in genetically homogeneous animal models of amyotrophic lateral sclerosis (ALS), an invariably fatal neurodegenerative disorder, can be informative of human pathology. The disease modifying effects in animal models of most therapeutic compounds have not been reproduced in patients. To advance therapeutics in ALS, we need easily accessible disease biomarkers which can discriminate across the phenotypic variants observed in ALS patients and can bridge animal and human pathology. Peripheral blood mononuclear cells alterations reflect the rate of progression of the disease representing an ideal biological substrate for biomarkers discovery.Methods
We have applied TMTcalibrator?, a novel tissue-enhanced bio fluid mass spectrometry technique, to study the plasma proteome in ALS, using peripheral blood mononuclear cells as tissue calibrator. We have tested slow and fast progressing SOD1G93A mouse models of ALS at a pre-symptomatic and symptomatic stage in parallel with fast and slow progressing ALS patients at an early and late stage of the disease. Immunoassays were used to retest the expression of relevant protein candidates.Results
The biological features differentiating fast from slow progressing mouse model plasma proteomes were different from those identified in human pathology, with only processes encompassing membrane trafficking with translocation of GLUT4, innate immunity, acute phase response and cytoskeleton organization showing enrichment in both species. Biological processes associated with senescence, RNA processing, cell stress and metabolism, major histocompatibility complex-II linked immune-reactivity and apoptosis (early stage) were enriched specifically in fast progressing ALS patients. Immunodetection confirmed regulation of the immunosenescence markers Galectin-3, Integrin beta 3 and Transforming growth factor beta-1 in plasma from pre-symptomatic and symptomatic transgenic animals while Apolipoprotein E differential plasma expression provided a good separation between fast and slow progressing ALS patients.Conclusions
These findings implicate immunosenescence and metabolism as novel targets for biomarkers and therapeutic discovery and suggest immunomodulation as an early intervention. The variance observed in the plasma proteomes may depend on different biological patterns of disease progression in human and animal model.96.
Rapid and Transient Activation of a Myelin Basic Protein Kinase in Tobacco Leaves Treated with Harpin from Erwinia amylovora 总被引:6,自引:0,他引:6 下载免费PDF全文
Harpins are bacterial protein elicitors that induce hypersensitive response-like necrosis when infiltrated into nonhost plants such as tobacco (Nicotiana tabacum L.) (Z.-M. Wei, R.J. Laby, C.H. Zumoff, D.W. Bauer, S.Y. He, A. Collmer, S.V. Beer [1992] Science 257: 85-88). Activity of a 49-kD Mg2+-dependent and Ca2+-independent kinase in tobacco leaves increased 50-fold 15 min after infiltration of harpin from Erwinia amylovora (harpinEa). Much less pronounced and more transient activation was detected in water-infiltrated leaves. Biochemical characteristics of the harpinEa-activated protein kinase (HAPK) activity are consistent with those of the mitogen-activated protein kinase family. HAPK is cytosolic and phosphorylates myelin basic protein on serine/threonine residues. Treatment with a protein tyrosine phosphatase completely eliminated HAPK activity, suggesting that tyrosine phosphorylation is required for posttranslational activation. Sustained HAPK activation after cycloheximide treatment implies that HAPK may be negatively regulated by a translation-dependent mechanism. The extracellular Ca2+ chelator EGTA or the protein kinase inhibitor K252a, infiltrated in planta together with harpinEa, partially blocked HAPK activation. The Ca2+-channel blocker La3+ had no effect on HAPK activation, suggesting that phosphorylation events precede and/or do not depend on the entry of extracellular Ca2+ into the cell. These results suggest that early signal transduction events during harpinEa- induced hypersensitive response elicitation depend in part on the activation of HAPK. 相似文献
97.
Alcala Josefina Giovannoni James J. Pike Leonard M. Reddy Avutu S. 《Molecular breeding : new strategies in plant improvement》1997,3(6):495-502
Genetic Bit Analysis (GBA) is a relatively new technique developed to score single-nucleotide polymorphisms among alleles. It is currently being used as a genetic diagnostic tool in human paternity tests as well as in pedigree analysis of farm animals. GBA relies on the polymerase chain reaction and enzyme-linked colorimetry to distinguish differences among genotypes. The identification of a single-nucleotide polymorphism which distinguished the plastome of cytoplasmic male-sterile onion varieties from the plastome of fertile lines provided a model system for testing the utility of GBA in plants. Our results demonstrate that GBA permits rapid and accurate allele determination in onion breeding lines, resulting in accurate prediction of sterility at the seedling stage. The use of 96-well microtiter plates and automated liquid-handlers allowed semi-automation of Genetic Bit Analysis. 相似文献
98.
The dark reactions of Secale cereale L. cv. Balbo phytochrome have been investigated in coleoptile tips and in extensively purified extracts of large molecular weight phytochrome. Destruction, but not reversion, was detected in vivo. The effects of various inhibitors of an in vitro phytochrome-degrading protease did not support a view of proteolytic attack as the basis of in vivo destruction. In vitro, rye phytochrome (about 240,000 molecular weight) reverted extremely rapidly, even at 5 C. The reversion curves were resolved into two first order components. The previously studied 60,000 molecular weight species, obtained by controlled proteolysis of large rye phytochrome, showed a similar two-component pattern, but a much slower over-all reversion rate. This reduction in rate was caused mainly by the reversion of a greater percentage of the small phytochrome as the slow component. Sodium dithionite markedly accelerated the reversion rate of both large and small forms, but oxidants, at concentrations low enough to avoid chromophore destruction, had no effect. Both large and small crude Avena sativa L. phytochrome showed two-component reversion kinetics. 相似文献
99.
The determination of 2'-O-methylnucleosides in RNA 总被引:6,自引:0,他引:6
A rapid and sensitive procedure is described for determining the 2′-O-methylnucleoside methylnucleoside composition of an RNA sample. The RNA is enzymatically hydrolyzed to nucleosides and the 2′-O-methylnucleoside fraction is isolated by DEAE-cellulose (borate) column chromatography. Boric acid is removed as its methyl ester and the 2′-O-methylnucleosides are resolved by liquid chromatography in the presence of ethylene glycol. The sensitivity of this method is sufficient to distinguish RNA samples which differ only 2–3% in 2′-O-methylnucleoside composition. 相似文献
100.
Rapid Phytochrome-mediated Changes in Adenosine 5'-Triphosphate Content of Etiolated Bean Buds 下载免费PDF全文
This study was designed to determine the effects of red and far red irradiation on ATP metabolism in etiolated bean buds (Phaseolus vulgaris L. var. Red Kidney). Compared to dark controls, red irradiated buds show an initial decline in ATP content at 15 seconds following a 5-minute irradiation. ATP content then rapidly rises to a peak at 1 minute, and then slowly returns to the baseline. The 1-minute promotion of ATP content is red/far red reversible. Acetylcholine does not appear to mimic red light in this system; it causes a marked decrease in ATP content. 相似文献