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排序方式: 共有960条查询结果,搜索用时 31 毫秒
951.
952.
Hailong Zhang Shupeng Li Pingting Liu Frankie H. F. Lee Albert H. C. Wong Fang Liu 《Proteomics》2017,17(8)
Cullin 4B (CUL4B) mutations have been implicated in mental retardation and dopamine‐related behaviors due to disruptions in their interaction with cullin‐RING E3 ligases (CRLs). Thus, further identification of CUL4B substrates can increase the knowledge of protein homeostasis and illuminate the role of CUL4B in neuropsychiatric disease. However, the transient nature of the coupling between CUL4B and its substrates is difficult to detect in vivo using current approaches, thus hampers efforts to investigate functions of CRLs within unperturbed living systems. In this study, we sought to discover CUL4B interactants with or without dopamine stimulation. BirA (118G) proximity‐dependent biotin labeling combined with LC‐MS was employed to biotinylate and identify transient and weak interactants of CUL4B. After purification with streptavidin beads and identified by LC‐MS, a total of 150 biotinylated proteins were identified at baseline condition, 53 of which are well‐known CUL4B interactants. After dopamine stimulation, 29 proteins disappeared and were replaced by 21 different protein interactants. The altered CUL4B interactants suggest that CUL4B regulates protein turnover and homeostasis in response to dopamine stimulation. Our results demonstrate the potential of this approach to identify novel CUL4B‐related molecules in respond to cellular stimuli, which may be applied to other types of signaling pathways. 相似文献
953.
IAN S. PEARSE 《Ecological Entomology》2011,36(5):635-642
1. Leaves possess traits that mediate the preference and performance of herbivores. Most evidence for the importance of leaf traits as defences against herbivory comes from studies of few model plant species. 2. In a phylogenetically explicit comparison, I explain the differences in preference and performance of tussock moth (Orgyia vetusta Boisduval) larvae on leaves of 27 oak (Quercus) species using nine putative leaf defences. 3. The preference for an oak species correlated positively with the survival of caterpillars. The correlation between preference and performance did not differ between oak species native to the range of tussock moth versus those from outside the herbivore's range. 4. The first principal component of leaf traits predicted survival of caterpillars on oak leaves but only marginally predicted their preference between oak species. A multiple regression model showed that evergreenness, toughness, and condensed tannin content were the best predictors of caterpillar survival, and leaf toughness was the best predictor of host preference. 5. Generalist caterpillars may accurately assess the value of novel food sources. Moreover, many leaf traits that have been found to affect herbivory within a plant species can also be used to predict the fitness of a generalist herbivore between species. 相似文献
954.
Molecular approaches towards development of novel Bacillus thuringiensis biopesticides 总被引:4,自引:0,他引:4
Bacillus thuringiensis (Bt) has been used for control of lepidopteran, dipteran and coleopteran insects for over three decades. Novel Bt strains
harbouring new types of insecticidal genes are being discovered worldwide. Recombinant strains with enhanced toxicity and
broadened insecticidal spectrum have been constructed. To increase the field persistence of insecticidal crystal proteins
(ICPs), alternative modes of their delivery in Pseudomonas sp. and endophytes have been developed. ICPs have been modified by site-directed mutagenesis to improve their insecticidal
efficacy. Higher yields of ICPs have been achieved by use of strong expression promoters and other regulatory elements. Gene-disabling
of the sporulation-specific protease has led to yield enhancement of ICPs. Interestingly, Bt toxins have been found to act
synergistically with some other pesticidal agents. Optimization of fermentation conditions is an essential requirement for
cost-effective commercial production of Bt biopesticides. The environmental impact of deployment of genetically engineered
biopesticides has been assessed. Recombinant Bt strains that do not carry any non-Bt DNA, endophytes, encapsulation in killed
bacteria (such as Pseudomonas) and asporogenous Bt strains are ecologically safe approaches. Efficient resistance management strategies require judicious
use of Bt transgenic plants in conjunction with refugia and Bt biopesticides in an Integrated Pest Management (IPM) program.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
955.
956.
Horizontal gene transfer and bacterial diversity 总被引:7,自引:0,他引:7
Bacterial genomes are extremely dynamic and mosaic in nature. A substantial amount of genetic information is inserted into
or deleted from such genomes through the process of horizontal transfer. Through the introduction of novel physiological traits
from distantly related organisms, horizontal gene transfer often causes drastic changes in the ecological and pathogenic character
of bacterial species and thereby promotes microbial diversification and speciation. This review discusses how the recent influx
of complete chromosomal sequences of various microorganisms has allowed for a quantitative assessment of the scope, rate and
impact of horizontally transmitted information on microbial evolution. 相似文献
957.
G. Wingsle 《Physiologia plantarum》1989,76(1):24-30
Changes in the excitability of the liverwort Conocephalum conicum L. caused by inhibitors of ionic channels and phosphorylation uncouplers, were examined. Action potentials were triggered by electrical and light stimuli. Tetraethylammonium chloride, an inhibitor of K+ channels, completely blocked the ability to generate action potentials. Excitability also disappeared under the influence of MnCl2 and LaCl3 , inhibitors of Ca2+ channels. The participation of Ca2+ and K+ in the electrogenesis of action potentials in C. conicum is discussed. Treatment with phosphorylation uncouplers induced a gradual disappearance of the metabolic component of the resting potential. It was accompanied by some series of excitations, numbering from several to over a dozen impulses characterized by decreasing amplitudes, after which the organism became totally unexcitable. Dicyclohexylcarbodiimide an inhibitor of H+ -ATPase, also caused depolarization of the transmembrane potential and disappearance of excitability. The results indicated the participation of a metabolic component in the generation of action potentials in C. conicum . 相似文献
958.
H Varewyck C Renard B Kristensen Y Bouquet M Vaiman A Van de Weghe A Van Zeveren 《Animal genetics》1990,21(1):59-68
Eighty anti-SLA class I reagents were prepared resulting from skin graft and subcutaneous immunizations in 320 fattening pigs of the Belgian Landrace and Pietrain breeds. By means of these alloantisera seven internationally and five locally established specificities were recognized. Three of the locally assigned specificities were new: BM 36, BM 37 and BM 38. They were serologically and genetically defined. The typing battery was completed with French and Danish reagents, and correlation coefficients were calculated for the main alloantisera recognizing SLA class I alloantigens observed in the Belgian breeds. The SLA haplotype frequencies were estimated in 372 Belgian Landrace and 369 Pietrain pigs. The SLA haplotype distribution differs significantly between both breeds and the genetic distance (0.54) at the SLA system is quite high. 相似文献
959.
Philip W. Bateman 《Ecological Entomology》1998,23(4):473-475
Abstract .1. To benefit from the putative genetic advantages of multiple mating with multiple partners, female insects would be expected to select against mating with the same male twice when another potential partner is present.
2. This paper examined whether female Gryllus bimaculatus (Gryllidae) preferred to mate with a novel partner over a partner with which they had mated previously.
3. Females presented with a choice preferred significantly to mate with novel males over previously mated males, and preferred to do so even when the potentially confounding influence of male–male competition was controlled for.
4. The potential advantages of such a mate choice pattern and possible ways in which the choice is mediated are discussed. 相似文献
2. This paper examined whether female Gryllus bimaculatus (Gryllidae) preferred to mate with a novel partner over a partner with which they had mated previously.
3. Females presented with a choice preferred significantly to mate with novel males over previously mated males, and preferred to do so even when the potentially confounding influence of male–male competition was controlled for.
4. The potential advantages of such a mate choice pattern and possible ways in which the choice is mediated are discussed. 相似文献
960.
Previous studies with the Brattleboro rat suggested a possible interaction at the pituitary level between AVP and the neuropeptide, F-8-F-NH2. In order to test this hypothesis, we studied the effect of various osmotic stimuli on neurohypophyseal F-8-F-NH2. In rats drinking 2% NaCl solution for two days, neural lobe AVP and F-8-F-NH2 levels were equally reduced by 87%. After maximal depletion, pituitary levels of F-8-F-NH2 and AVP rebounded in parallel when normal drinking water was reintroduced. Pituitary stalk transection depleted neurohypophyseal F-8-F-NH2. The results of this study suggest that neurohypophyseal F-8-F-NH2 originates from the hypothalamus and, furthermore, is coreleased along with AVP in response to hyperosmotic stimuli. 相似文献