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101.
Effects of Melatonin on Growth,Physiology and Gene Expression in Rice Seedlings Under Cadmium Stress
Xiachen Lv Yunxia Fang Lantian Zhang Weiyi Zhang Ling Xu Jingjin Han Bailing Jin Xian Zhang Xiaoqin Zhang Dawei Xue 《Phyton》2019,88(2):91-100
Melatonin (MLT) is a hormonal substance found in many organisms and can improve plant stress resistance. In this study, the japonica rice variety Y32 and indica rice variety NJ6 were cultivated in hydroponics under different concentrations of CdCl2 at the two-leaf stage. The growth, physiological and biochemical responses of the seedlings and the expression of cadmium (Cd)-related genes under exogenous melatonin (MLT) treatment were assessed. The results indicated that Cd stress destroyed the dynamic balance between reactive oxygen species (ROS) production and removal, resulting in ROS accumulation, membrane lipid peroxidation, and impaired growth and development. Following the application of exogenous MLT to rice seedlings, increases in plant biomass including both underground and above-ground areas were observed. MLT also scavenged the inhibition of superoxide dismutase (SOD) and peroxidase (POD) in a concentration dependent manner in response to Cd stress. Catalase (CAT) activity and malondialdehyde (MDA) expression also decreased following MLT treatment. Amongst the six Cd-related genes assessed, five genes were down-regulated and one was up-regulated in response to MLT treatment. Taken together, these data demonstrate that MLT improves the resilience of rice seedlings at the biochemical, physiological, and molecular levels, and diminishes the damage caused by Cd stress. 相似文献
102.
Fusions between the green fluorescent protein (GFP) and the Cauliflower mosaic virus (CaMV) movement protein (MP) induce the formation of fluorescent foci and surface tubules in Arabidopsis thaliana leaf mesophyll protoplasts. Tubules elongate coordinately and progressively in an assembly process approximately 6 to 12 h following transfection of protoplasts with GFP-MP constructs. Tubules are not formed in protoplasts transfected by GFP-MP(ER2A), a MP mutation that renders CaMV noninfectious. A small number of short tubules are formed on protoplasts transfected by GFP-MP(N6) and GFP-MP(N13), two second-site revertants of ER2A that partially restore infectivity. Protoplasts cotransfected with cyan fluorescent protein (CFP)-MP(WT) and GFP-MP(ER2A) form tubules containing both MP fusions, indicating that although the GFP-MP(ER2A) cannot induce tubule formation, GFP-MP(ER2A) can coassemble or colocalize with CFP-MP(WT) in tubules. Thus, CaMV MP-induced tubule formation in protoplasts correlates closely with the infectivity of mutation ER2A and its revertants, suggesting that tubule-forming capacity in plant protoplasts reflects a process required for virus infection or movement. 相似文献
103.
Associations between different agonistic and affiliative behavioural patterns of female domestic cats (Felis silvestris catus) were studied. In three groups of intact cats living in confinement frequencies of fourteen agonistic and affiliative behavioural
patterns were recorded. The technique of factor analysis (Principal Components Analysis followed by varimax rotation on a
dyads X behavioural patterns matrix) was used to detect clusters in these behavioural patterns. Five factors (or types of
interindividual relationships) were extracted per group. They accounted collectively for at least 77% of the total variance
present in the data. Although differences existed between groups with respect to behavioural patterns included in each factor,
four clusters of behaviours could be discriminated: (I) social rubbing, lordosis and rolling in front of partner (sexual behaviour),
(II) allogrooming, social sniffing, nosing, sniffing rear and treading (inspection-affiliative behaviour), (III) offensive
behaviour and staring, and (IV) defensive behaviour and staring. The role of these clusters in group living is discussed. 相似文献
104.
The sectioned thin cell layers (TCL) of flower stalk of Cichorium intybus L. were cultured in MS medium supplemented with NAA and BA or IAA and BA where floral and vegetative buds were developed from the explant. Endogenous IAA, DHZ+DHZR, iPA increased significantly during the floral bud formation, while Z+ZR remained changed. The levels of cytokinins, DHZ +DHZR, iPA, and Z-f-ZR all increased significantly during the vegetative bud formation, however IAA level was reduced during the first 7 days of culture and increased to two-thirds of initial values on the day when the bud primordia were formed. The results suggested that the initiation of floral buds was associated with a high IAA/CTK ratio, whereas the induction of vegetative bud differentiation was related to a low IAA/CTK ratio. 相似文献
105.
Novobiocin blocks the Drosophila heat shock response 总被引:12,自引:0,他引:12
106.
Pei-pei Han Shi-ru Jia Ying Sun Zhi-lei Tan Cheng Zhong Yu-jie Dai Ning Tan Shi-gang Shen 《World journal of microbiology & biotechnology》2014,30(9):2407-2418
The application of antibiotic treatment with assistance of metabolomic approach in axenic isolation of cyanobacterium Nostoc flagelliforme was investigated. Seven antibiotics were tested at 1–100 mg L?1, and order of tolerance of N. flagelliforme cells was obtained as kanamycin > ampicillin, tetracycline > chloromycetin, gentamicin > spectinomycin > streptomycin. Four antibiotics were selected based on differences in antibiotic sensitivity of N. flagelliforme and associated bacteria, and their effects on N. flagelliforme cells including the changes of metabolic activity with antibiotics and the metabolic recovery after removal were assessed by a metabolomic approach based on gas chromatography–mass spectrometry combined with multivariate analysis. The results showed that antibiotic treatment had affected cell metabolism as antibiotics treated cells were metabolically distinct from control cells, but the metabolic activity would be recovered via eliminating antibiotics and the sequence of metabolic recovery time needed was spectinomycin, gentamicin > ampicillin > kanamycin. The procedures of antibiotic treatment have been accordingly optimized as a consecutive treatment starting with spectinomycin, then gentamicin, ampicillin and lastly kanamycin, and proved to be highly effective in eliminating the bacteria as examined by agar plating method and light microscope examination. Our work presented a strategy to obtain axenic culture of N. flagelliforme and provided a method for evaluating and optimizing cyanobacteria purification process through diagnosing target species cellular state. 相似文献
107.
108.
Hong MY Lee EM Jo YH Park HC Kim SR Hwang JS Jin BR Kang PD Kim KG Han YS Kim I 《Gene》2008,413(1-2):49-57
The 15,360-bp long complete mitogenome of Caligula boisduvalii possesses a gene arrangement and content identical to other completely sequenced lepidopteran mitogenomes, but different from the common arrangement found in most insect order, as the result of the movement of tRNA(Met) to a position 5'-upstream of tRNA Ile. The 330-bp A+T-rich region is apparently capable of forming a stem-and-loop structure, which harbors the conserved flanking sequences at both ends. Dissimilar to what has been seen in other sequenced lepidopteran insects, the initiation codon for C. boisduvalii COI appears to be TTG, which is a rare, but apparently possible initiation codon. The ATP8, ATP6, ND4L, and ND6 genes, which neighbor another PCG at their 3' end, all harbored potential sequences for the formation of a hairpin structure. This is suggestive of the importance of such structures for the precise cleavage of the mRNA of mature PCGs. Phylogenetic analyses of available sequenced species of Bombycoidea, Pyraloidea, and Tortricidea supported the morphology-based current hypothesis that Bombycoidea and Pyraloidea are monophyletic (Obtectomera). As previously suggested, Bombycidae (Bombyx mori and B. mandarina) and Saturniidae (Antheraea pernyi and C. boisduvalii) formed a reciprocal monophyletic group. 相似文献
109.
Previously, we reported that Phe105 in transmembrane domain 2 of the mouse dopamine transporter (DAT) is crucial for high-affinity cocaine binding. In the current study, we investigated whether other residues surrounding Phe105 also affect the potency of cocaine inhibition. After three rounds of sequential random mutagenesis at these residues, we found a triple mutant (L104V, F105C and A109V) of mouse DAT that retained over 50% uptake activity and was 69-fold less sensitive to cocaine inhibition when compared with the wild-type mouse DAT. The triple mutation also resulted in a 47-fold decrease in sensitivity to methylphenidate inhibition, suggesting that the binding sites for cocaine and methylphenidate may overlap. In contrast, the inhibition of dopamine uptake by amphetamine or methamphetamine was not significantly changed by the mutations, suggesting that the binding sites for the amphetamines differ from those for cocaine and methylphenidate. Such functional but cocaine-insensitive DAT mutants can be used to generate a knock-in mouse line to study the role of DAT in cocaine addiction. 相似文献
110.
Spatial patterns,ecological niches,and interspecific competition of avian brood parasites: inferring from a case study of Korea 下载免费PDF全文
Jin‐Won Lee Hee‐Jin Noh Yunkyoung Lee Young‐Soo Kwon Chang‐Hoe Kim Jeong‐Chil Yoo 《Ecology and evolution》2014,4(18):3689-3702
Since obligate avian brood parasites depend completely on the effort of other host species for rearing their progeny, the availability of hosts will be a critical resource for their life history. Circumstantial evidence suggests that intense competition for host species may exist not only within but also between species. So far, however, few studies have demonstrated whether the interspecific competition really occurs in the system of avian brood parasitism and how the nature of brood parasitism is related to their niche evolution. Using the occurrence data of five avian brood parasites from two sources of nationwide bird surveys in South Korea and publically available environmental/climatic data, we identified their distribution patterns and ecological niches, and applied species distribution modeling to infer the effect of interspecific competition on their spatial distribution. We found that the distribution patterns of five avian brood parasites could be characterized by altitude and climatic conditions, but overall their spatial ranges and ecological niches extensively overlapped with each other. We also found that the predicted distribution areas of each species were generally comparable to the realized distribution areas, and the numbers of individuals in areas where multiple species were predicted to coexist showed positive relationships among species. In conclusion, despite following different coevolutionary trajectories to adapt to their respect host species, five species of avian brood parasites breeding in South Korea occupied broadly similar ecological niches, implying that they tend to conserve ancestral preferences for ecological conditions. Furthermore, our results indicated that contrary to expectation interspecific competition for host availability between avian brood parasites seemed to be trivial, and thus, play little role in shaping their spatial distributions and ecological niches. Future studies, including the complete ranges of avian brood parasites and ecological niches of host species, will be worthwhile to further elucidate these issues. 相似文献