木薯MeCML24与MeSAUR1互作调控MeAGPS1a表达的功能验证

木薯是华南地区重要的经济作物,其块根富含淀粉。解析木薯块根淀粉合成调控机理将有助于木薯高产、高淀粉分子改良。AGPase由大亚基和小亚基构成,催化1-磷酸葡萄糖和ATP形成腺苷二磷酸葡萄糖和焦磷酸,其中腺苷二磷酸葡萄糖为淀粉生物合成的底物。AGPase酶是植物淀粉合成的限速酶,提高AGPase酶活性,有利于作物淀粉的积累及产量的提高。木薯MeAGPS1a基因编码的小亚基是AGPase的催化中心,前期研究表明生长素响应因子MeSAUR1作为转录因子正调控MeAGPS1a基因表达,酵母双杂交筛选木薯cDNA文库显示钙调素类似蛋白（CaM-like, CML）成员MeCML24为MeSAUR1的候选互作蛋白。为了确定MeCML24和MeSAUR1的互作关系,本研究从‘SC8’木薯品种基因组克隆了MeCML24基因,该基因的CDS区长度为492 bp,编码163个氨基酸。MeCML24蛋白的理化性质及二级结构分析显示,该蛋白理论等电点pI值4.38,属于亲水性蛋白,α-螺旋占52.76%,无规则卷曲占30.06%,β-转角结构占11.04%。构建酵母双杂交载体BD-MeCML24,自激活实验表...     

基于NRF24E1无线奶牛体温数据采集系统设计

奶牛体温是衡量奶牛健康状况的重要参数,定时采集奶牛体温对于判断奶牛的健康状况有着重要意义。人们对于数据传输大多采用有线方式,但牛舍环境不便于铺设线缆进行数据传输。为此,本系统利用收发芯片NRF24E1进行设计,实现了奶牛体温数据采集系统与上位机进行无线通信,满足了对奶牛体温数据实时监测的要求,提高了对奶牛体温数据采集的自动性和高效性。通过芯片的选型以及芯片外围电路的改进优化了硬件电路,并且设计了有效的通信协议,防止传输的数据信号产生畸变并具有自动剔除错误信号的能力。该系统对多头奶牛的体温进行了测量,试验表明,本系统具有较高的实用性和可靠性,成本低功耗低,具有良好的应用前景。     

2017年中国部分地区白斑综合征病毒高变异区的序列分析

白斑综合征病毒(WSSV)自暴发以来给全球范围内的对虾养殖产业带来了巨大的损失。为了解我国凡纳滨对虾(Litopenaeus vannamei)养殖区WSSV的流行变异情况,选取2017年中国部分地区的42个WSSV阳性样本,对ORF14/15、ORF23/24、ORF75、ORF94和ORF125共5个可变区进行PCR特异性扩增,分析其序列的缺失变异和重复单元(Ru)中单核苷酸多态性的变化。研究结果显示,在ORF14/15的扩增中共出现4种缺失片段;ORF23/24只出现11945bp的缺失片段;ORF75扩增中,总RUs数目为3、4、9,其中45bp的RUs在12、27、80位点发生多核苷酸多态性;ORF94的RUs数目为6,其各重复单元在48位发生单核苷酸多态性;ORF125的RUs数目为4、6、7不等,其各重复单元分别在20、27、50、53、61位发生碱基突变。研究结果表明,2017年样本中,WSSV在中国大部分地区均出现一定程度的缺失变异,其中部分可变区表现出缺失情况的稳定性,某些可变区的重复单元数目及SNP表现出地区的差异性以及不稳定性。     

Effects of Exogenous 24-epibrassinolide on Photosynthetic Physiology of CottonSeedlings under Low Temperature

[Objective] The objective of this study was to investigate the effects of exogenous 24-epibrassinolide (EBR) on the photosynthetic physiology of cotton seedlings under low temperature and to provide basis for improving the cold tolerance of cotton by using EBR as growth regulator. [Method] Taking CCRI 60, Lumianyan 28 and Simian 3 as materials, a field experiment was carried out in Institute of Cotton Research of CAAS(Anyang county, Henan province). Before the first low temperature treatment, the cotton seedlings were sprayed with distilled water (Control) and different concentrations of EBR (0.1 mg·L^－1 and 0.2 mg·L^－1), respectively. After 3 days, the relative electrical conductivity, chlorophyll content, rapid chlorophyll fluorescence induction kinetic curve (OJIP) and fluorescence parameters were measured. [Result] Under low temperature, the relative conductivity of CCRI 60, Lumianyan 28 and Simian 3 spraying with EBR decreased by 17.7%～32.8% compared with control, and there was no significant difference between CCRI 60 and Lumianyan 28 in different concentrations of EBR treatments, butthe relative conductivity of Simian 3 treating with 0.2 mg·L^－1 EBR was significantly lower than those treatments with 0.1 mg·L^－1 EBR . The chl a and chl b contents increased by 9.7%～32.6% and 15.0%～18.9%, respectively. The maximum photochemical efficiency of photosystemⅡ (F_v/F_M) and photosynthetic performance index on absorption basis(PI_ABS) increased significantly. PI_ABS of CCRI 60 increase the maximum by 75.6% using 0.1 mg·L^－1 EBR. Lumianyan 28 and Simian 3 increased the maximum by 101.1% and 265.6% using 0.2 mg·L^－1 EBR, respectively; Absorbed photon flux per cross section (ABS/CSm), electron transport flux (further than QA) per active reactive center (ETo/RC) and probability for electron transport (φEo) are significantly increased. [Conclusion] Exogenous EBR can enhance the ability of low temperature tolerance of cotton seedlings and alleviate the inhibition of photosynthesis in cotton at low temperature. The study showed that 0.1 mg·L^－1 EBR performs well in CCRI 60 and 0.2 mg·L^－1 in Lumianyan 28 and Simian 3.     

Synthesis of strigolactones,a strategic account

Strigolactones (SLs) constitute a new class of plant hormones that have received growing interest in recent years. They firstly became known as signalling molecules for host recognition by parasitic plants, and for symbiosis of plants with arbuscular mycorrhizal fungi. Furthermore, they are involved in numerous physiological processes in plants, such as the regulation of plant architecture and the response to abiotic factors. SLs are produced by plants in extremely low quantities, and they may be unstable during the purification process. Therefore, their total synthesis is highly relevant for confirming the structures assigned on the basis of spectroscopic and other physical data. A second important theme in SL research is the design and synthesis of SL analogues that have a simplified structure while still featuring the essential bioproperties. This review summarises the strategy and synthesis of naturally occurring SLs, and the design and synthesis of SL analogues with appreciable bioactivity. © 2015 Society of Chemical Industry     

24-表油菜素内酯对酿酒葡萄白藜芦醇诱导合成的影响

以‘赤霞珠’(Cabernet sauvignon)和‘蛇龙珠’(‘Cabernet gernischt’)葡萄果实为试材,在葡萄浆果生长期设置0(对照)、0.05、0.1、0.5mg·L~(-1)的24-表油菜素内酯(EBR)处理,研究不同质量浓度的24-表油菜素内酯处理对葡萄果皮白藜芦醇(Res)质量分数的影响,同时探讨葡萄果皮中白藜芦醇质量分数与苯丙氨酸解氨酶(PAL)、肉桂酸4-羟基化酶(C4H)、4-香豆酸辅酶A连接酶(4CL)活性的关系。结果表明,在葡萄果实生长发育过程中,‘赤霞珠’和‘蛇龙珠’果皮中白藜芦醇质量分数变化出现2次高峰,分别在花后35d和花后80d。PAL、C4H、4CL活性变化与果皮中白藜芦醇质量分数变化相一致。不同质量浓度的EBR处理对葡萄白藜芦醇有显著的诱导效果,其中以0.1mg·L~(-1) EBR诱导效果最好。由此推断,适宜质量浓度的EBR处理可能激活相关酶的活性,进一步提高葡萄白藜芦醇质量分数。     

外源油菜素内酯对茶树光合特性的影响

24-表油菜素内酯（EBR）是一种重要的植物激素,在植物对多种逆境的抵抗中发挥着重要的作用。本试验以田间龙井43、清明早和香菇寮白毫茶树品种为试验材料,研究了外源EBR处理对茶树叶片光合特性、Rubisco与FBPase活性及其相关基因表达量的影响。结果表明外源EBR（0.1βmg·L^-1）处理后,龙井43、清明早和香菇寮白毫的叶片净光合速率分别提高了49.06%、45.49%和92.34%;最大羧化速率（Vc_max）分别提高了21.82%、21.68%和33.47%,最大再生速率（J_max）分别提高了17.16%、23.86%和23.23%;Rubisco和FBPase活性显著提高（P<0.05）;Rubisco和FBPase相关基因表达量显著（P<0.05）提高。可见,外源EBR可以通过调控基因表达提高茶树叶片中Rubisco和FBPase的活性以及Rubisco最大羧化速率和RuBP的最大再生速率,从而促进茶树光合碳固定,提高茶树的光合速率。     

24-表油菜素内酯对盐碱胁迫下大豆生育、生理及细胞超微结构的影响

【目的】探讨外源EBR(24-表油菜素内酯)对盐碱复合胁迫下大豆的生长指标、生理特性及超微结构的影响,为改善大豆生长、保障粮食安全、实现农业可持续发展奠定基础。【方法】以大豆品种黑农44号为试材,分别在110 mmol·L~(-1)的盐碱复合胁迫条件下培养3 d和7 d进行取材,研究1.2 mg·L~(-1)外源EBR对大豆株高、根系生长,叶片3种抗氧化酶超氧化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)及抗坏血酸过氧化物酶(ascorbate peroxidase,APX)活性,相对电导率、超氧阴离子(O_2~-)产生速率、过氧化氢(H_2O_2)和丙二醛(malondialdehyde,MDA)含量、游离脯氨酸和叶绿素含量以及叶片和根尖细胞超微结构的影响。【结果】盐碱胁迫处理3 d和7 d时,与对照组相比,3种抗氧化酶(SOD、POD、APX)的活性、游离脯氨酸含量、相对电导率、O_2~-产生速率、H_2O_2和MDA含量均升高;各项生长指标、叶绿素含量均降低;叶片细胞结构中叶绿体和线粒体遭到严重破坏;根尖细胞中线粒体、内质网结构破坏较重,液泡破裂。盐碱胁迫条件下,施加外源EBR使大豆的株高、根长和根鲜重分别提高了6.45%、9.60%和19.85%;使大豆叶片SOD、POD、APX的活性显著升高,在3 d和7 d时分别增加了16.92%和9.68%、48.85%和61.44%、19.05%和20.36%;相对电导率、O_2~-产生速率、H_2O_2和MDA的含量显著降低,分别降低了19.58%和28.26%、28.06%和40.92%、28.62%和31.21%、31.03%和37.17%;脯氨酸和叶绿素含量显著升高,分别升高了3.67%和15.96%、13.34%和16.87%;同时维护了大豆叶片和根尖细胞超微结构的稳定性,延缓了细胞的衰老、解体。【结论】在盐碱胁迫下,施加外源EBR通过提高抗氧化酶活性和脯氨酸及叶绿素含量,降低了活性氧(ROS)的积累,维护了细胞结构的完整,促进了幼苗生长,增强了大豆幼苗耐盐碱胁迫的能力。     

木霉REMI转化体耐热机理的初步研究

本文利用蛋白质电泳、基因克隆和荧光定量PCR等技术对耐高温木霉REMI转化体的抗逆机理进行了初步研究。结果表明,耐高温木霉REMI转化体的蛋白质谱带明显多于出发菌株T21,且差异主要集中在Rf值大于0.593的区域,该区域主要是小分子的热休克蛋白,说明影响耐高温木霉REMI转化体对温度耐受性的蛋白主要以小分子量蛋白质为主。对其中一种热休克蛋白HSP24的基因进行克隆、测序,结果表明不同木霉REMI转化体和出发菌株T21间该基因序列没有差异,但经荧光定量PCR对HSP24基因转录检测表明,耐高温木霉REMI转化体的热激蛋白HSP24的表达量有所增加,从而表明REMI插入提高了该基因的转录水平。