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71.
72.
Expression of baculovirus anti-apoptotic genes p35 and op-iap in cotton (Gossypium hirsutum L.) enhances tolerance to verticillium wilt 总被引:1,自引:0,他引:1
Background
Programmed cell death plays an important role in mediating plant adaptive responses to the environment such as the invasion of pathogens. Verticillium wilt, caused by the necrotrophic pathogen Verticillium dahliae, is a serious vascular disease responsible for great economic losses to cotton, but the molecular mechanisms of verticillium disease and effective, safe methods of resistance to verticillium wilt remain unexplored.Methodology/Principal Findings
In this study, we introduced baculovirus apoptosis inhibitor genes p35 and op-iap into the genome of cotton via Agrobacterium-mediated transformation and analyzed the response of transgenic plants to verticillium wilt. Results showed that p35 and op-iap constructs were stably integrated into the cotton genome, expressed in the transgenic lines, and inherited through the T3 generation. The transgenic lines had significantly increased tolerance to verticillium wilt throughout the developmental stages. The disease index of T1–T3 generation was lower than 19, significantly (P<0.05) better than the negative control line z99668. After treatment with 250 mg/L VD-toxins for 36 hours, DNA from negative control leaves was fragmented, whereas fragmentation in the transgenic leaf DNA did not occur. The percentage of cell death in transgenic lines increased by 7.11% after 60 mg/L VD-toxin treatment, which was less than that of the negative control lines''s 21.27%. This indicates that p35 and op-iap gene expression partially protects cells from VD-toxin induced programmed cell death (PCD).Conclusion/Significance
Verticillium dahliae can trigger plant cells to die through induction of a PCD mechanism involved in pathogenesis. This paper provides a potential strategy for engineering broad-spectrum necrotrophic disease resistance in plants. 相似文献73.
山东强筋和中筋小麦品质形成的气象条件及区划 总被引:4,自引:0,他引:4
1999—2003年选用4个强筋小麦品种和12个中筋小麦品种在山东省的31个县进行试验,以各试验点当地气象站观测的小麦开花至成熟期的气象资料为依据,采用逐步回归和一元非线性回归模型进行分析.结果表明:平均气温分别为20.0℃和20.5℃时,有利于强筋和中筋小麦面团稳定时间的延长;气温日较差分别为12.7℃和11.7℃时,有利于强筋和中筋小麦籽粒蛋白质含量的提高;降水量分别为48.6mm和52.1mm,日照时数分别为297h和299h时,有利于强筋和中筋小麦沉降值的提高;降水量分别为53.5mm和53.9mm,日照时数分别为295h和298h时,有利于强筋和中筋小麦面团稳定时间的延长.单一气象因子对小麦籽粒蛋白质含量、沉降值和面团稳定时间的影响不完全同步.依据对各地气象条件进行综合评价的结果,将山东省划分为胶东与鲁中强筋、中筋小麦适宜区,鲁西北和鲁西南强筋、中筋小麦次适宜区,鲁南强筋小麦次适宜、中筋小麦适宜区. 相似文献
74.
Shin DH 《Protein and peptide letters》2008,15(6):630-632
The phosphoenolpyruvate-carbohydrate phosphotransferase system (PTS) catalyzes the phosphorylation and transportation of its sugar substrates. A sugar-specific enzyme II complex involved in the PTS finally functions to translocate substrates across the membrane. A PTS EIIB(fruc) protein, a fructose specific EIIB subunit, from Escherichia coli has been cloned, expressed, refolded, purified, and crystallized. The synchrotron data were collected to 2.6 A from the crystal of a selenomethionine substitute PTS EIIB(fruc) protein. The crystal belongs to the primitive trigonal space group P3(1)21, with unit-cell parameters of a = 33.4 A, b = 33.4 A, c = 154.0 A, and beta = 120.0 degrees . A full structure determination is under way to provide insights into the structure-function relationships of this protein. 相似文献
75.
The type VI secretion systems (T6SS) have emerging roles in interspecies competition. In order to have an advantage in defense against other organisms, this system in Pseudomonas aeruginosa delivers a peptidoglycan amidase (Tse1) to the periplasmic space of a competitor. An immune protein (Tsi1) is also produced by the bacterium to protect itself from damage caused by Tse1. Tsi1 directly interacts with Tse1. We report that the crystal structure of Tse1 displays a common CHAP protein fold. Strikingly, our structures showed that the third residue in the catalytic triad may be novel as this residue type has not been observed previously. 相似文献
76.
繁缕和无瓣繁缕六个居群的数值分析 总被引:6,自引:0,他引:6
对繁缕(Stellaria media)和无瓣繁缕(S.apetala)的6个居群的57个性状进行Q-聚类和R-聚类的研究。结果表明:(1)Q-聚类中,用一条结合线,可以把繁缕的4个居群聚为一类,无瓣繁缕的2个居群聚为一类。这一结果支持肥繁缕和无瓣繁缕划分为两个物种;(2)R-聚类中,发现了呈现完全正相关、极大正相关和极大负相关的性状,并根据R-聚类的结果,运用一条适当的结合线,把繁缕和无瓣繁缕的57个性状划为5个类群,并分析了各性状的分类学意义。 相似文献
77.
The Chinese egret is a globally endangered species. Here we describe a set of primer pairs to amplify its entire mtDNA. The polymerase chain reaction products (1000–2000 bp) were successfully amplified by using this primer set and were then sequenced and aligned. The contiguous mtDNA sequences of the Chinese egret were assembled to be a circular molecule (17 579 bp). This primer set was also confirmed to be useful for six other species of ardeid birds. The versatility of this primer set will provide a groundwork for further studies on the genetic structure and molecular evolution of the ardeid species. 相似文献
78.
Response of rice (Oryza sativa) with root surface iron plaque under aluminium stress 总被引:1,自引:0,他引:1
BACKGROUND AND AIMS: Rice (Oryza sativa) is an aquatic plant with a characteristic of forming iron plaque on its root surfaces. It is considered to be the most Al-tolerant species among the cereal crops. The objective of this study was to determine the effects of root surface iron plaque on Al translocation, accumulation and the change of physiological responses under Al stress in rice in the presence of iron plaque. METHODS: The japonica variety rice, Koshihikari, was used in this study and was grown hydroponically in a growth chamber. Iron plaque was induced by exposing the rice roots to 30 mg L(-1) ferrous iron either as Fe(II)-EDTA in nutrient solution (6 d, Method I) or as FeSO(4) in water solution (12 h, Method II). Organic acid in root exudates was retained in the anion-exchange resin and eluted with 2 m HCl, then analysed by high-performance liquid chromatography (HPLC) after proper pre-treatment. Fe and Al in iron plaque were extracted with DCB (dithionite-citrate-bicarbonate) solution. KEY RESULTS AND CONCLUSIONS: Both methods (I and II) could induce the formation of iron plaque on rice root surfaces. The amounts of DCB-extractable Fe and Al on root surfaces were much higher in the presence of iron plaque than in the absence of iron plaque. Al contents in root tips were significantly decreased with iron plaque; translocation of Al from roots to shoots was significantly reduced with iron plaque. Al-induced secretion of citrate was observed and iron plaque could greatly depress this citrate secretion. These results suggested that iron plaque on rice root surfaces can be a sink to sequester Al onto the root surfaces and Fe ions can pre-saturate Al-binding sites in root tips, which protects the rice root tips from suffering Al stress to a certain extent. 相似文献
79.
Li M Liu L Xi N Wang Y Dong Z Tabata O Xiao X Zhang W 《Biochemical and biophysical research communications》2011,(2):689-694
The topography and mechanical properties of single B-lymphoma cells have been investigated by atomic force microscopy (AFM). With the assistance of microfabricated patterned pillars, the surface topography and ultrastructure of single living B-lymphoma cell were visualized by AFM. The apoptosis of B-lymphoma cells induced by rituximab alone was observed by acridine orange/ethidium bromide (AO/EB) double fluorescent staining. The rituximab-induced changes of mechanical properties in B-lymphoma cells were measured dynamically and the results showed that B-lymphoma cells became dramatically softer after incubation with rituximab. These results can improve our understanding of rituximab’effect and will facilitate the further investigation of the underlying mechanisms. 相似文献
80.
Zi-Yun Yi Qiu-Xia Liang Tie-Gang Meng Jian Li Ming-Zhe Dong Yi Hou 《Cell cycle (Georgetown, Tex.)》2019,18(4):395-412
PKCβI, a member of the classical protein kinase C family, plays key roles in regulating cell cycle transition. Here, we report the expression, localization and functions of PKCβI in mouse oocyte meiotic maturation. PKCβI and p-PKCβI (phosphor-PKCβI) were expressed from germinal vesicle (GV) stage to metaphase II (MII) stage. Confocal microscopy revealed that PKCβI was localized in the GV and evenly distributed in the cytoplasm after GV breakdown (GVBD), and it was concentrated at the midbody at telophase in meiotic oocytes. While, p-PKCβI was concentrated at the spindle poles at the metaphase stages and associated with midbody at telophase. Depletion of PKCβI by specific siRNA injection resulted in defective spindles, accompanied with spindle assembly checkpoint activation, metaphase I arrest and failure of first polar body (PB1) extrusion. Live cell imaging analysis also revealed that knockdown of PKCβI resulted in abnormal spindles, misaligned chromosomes, and meiotic arrest of oocytes arrest at the Pro-MI/MI stage. PKCβI depletion did not affect the G2/M transition, but its overexpression delayed the G2/M transition through regulating Cyclin B1 level and Cdc2 activity. Our findings reveal that PKCβI is a critical regulator of meiotic cell cycle progression in oocytes.
Abbreviations: PKC, protein kinase C; COC, cumulus-oocyte complexes; GV, germinal vesicle; GVBD, germinal vesicle breakdown; Pro-MI, first pro-metaphase; MI, first metaphase; Tel I, telophase I; MII, second metaphase; PB1, first polar body; SAC, spindle assembly checkpoint 相似文献