TcLr24小麦STK类抗病基因同源片段的分离和特征分析

利用根据STK类植物抗病基因类似序列保守结构设计的引物,对TcLr24小麦叶片cDNA进行扩增,通过RT-PCR扩增得到STK类抗病基因同源片段长度811bp,开放阅读框长804bp,编码268个通读的氨基酸序列,大小29.6kDa,理论等电点6.14,该氨基酸序列与多个小麦和燕麦蛋白激酶序列高度同源,含有激酶特征结构疏水信号序列及胞外结构域。     

Effects of down-regulation of X-linked inhibitor of apoptosis protein gene on docetaxel-induced apoptosis in bladder cancer cells

AIM: To observe the effects of down-regulation of X-linked inhibitor of apoptosis protein ( XIAP ) gene on the chemotherapeutic sensitivity of bladder cancer cells. METHODS: The shRNA and shRNA-XIAP were transfected into bladder cancer T24T cells. The fluorescence microscopy was used to detect the transfection effects. XIAP gene expression was detected by RT-PCR and Western blotting. Docetaxel was administrated to T24T, T24T shRNA and T24T shRNA-XIAP bladder cancer cells. ATPase methods was performed to measure in vitro cell viability. Morphological changes and apoptotic rates were determined by phase contrast microscopy and flow cytometry assay. Cellular poly(ADP-ribose) polymerase (PARP) and caspase-3 protein expression and their cleavage were assayed by Western blotting. RESULTS: The fluorescence was obvious in the T24T shRNA and T24T shRNA-XIAP cells under the fluorescence microscope. Using Western blotting and RT-PCR methods, the protein and mRNA levels of XIAP gene in T24T shRNA-XIAP cells were significantly decreased,respectively. After treated with various concentrations of docetaxel for 24 h, the IC₅₀ of T24T shRNA-XIAP cells was (1.23?0.62) nmol/L, lower than that of T24T and T24T shRNA cells, which were (8.22?1.23) and (8.35?0.98) nmol/L (P<0.01), respectively. Compared with control group, the typical morphological changes of apoptosis were observed in T24T shRNA-XIAP cells. Detected by flow cytometry assay, the apoptotic rates in shRNA-XIAP group were (41.45?6.23)% and (74.82?5.46)% after exposed to docetaxel at the concentrations of 2 nmol/L and 5 nmol/L for 24 h, which were significantly higher than that in T24T shRNA group with (25.34?3.81)% and (34.14?6.25)%, respectively (P<0.01). Compared with T24T shRNA cells, the cleavage of PARP and caspase-3 proteins in the cells transfected with shRNA-XIAP was significantly increased. CONCLUSION: XIAP gene is significantly down-regulated via shRNA-XIAP, which could increase the docetaxel-induced apoptosis and cytotoxic activity.     

低温胁迫下24-表油菜素内酯对辣椒种子萌发及幼苗生长的影响

以华椒15号辣椒种子为材料,采用浸泡法和添加法2种方法,研究低温(15℃)胁迫下不同质量浓度24-表油菜素内酯(EBR)对辣椒种子萌发及幼苗生长的影响。结果表明:在0.001～1.000mg/L质量浓度范围内,EBR对辣椒种子发芽势没有显著影响;浸泡法中,0.001～0.100mg/L的EBR对辣椒种子的萌发率产生显著促进作用,0.050mg/L时促进作用最强,发芽率达44.00%;添加法中,在设定的质量浓度范围内,EBR对辣椒种子的萌发率产生抑制作用,1.000mg/L时抑制作用达差异显著水平。浸泡法和添加法中,0.001～1.000mg/L的EBR对辣椒幼苗的根长均产生显著抑制作用,1.000mg/L时抑制作用最强。浸泡法中,0.010～1.000mg/L的EBR对辣椒幼苗的苗高产生显著促进作用,0.050mg/L时促进作用最强,平均苗高为1.82cm,比对照高0.62cm;而添加法中,EBR对辣椒幼苗的苗高不产生显著影响。浸泡法中,0.001～1.000mg/L的EBR对辣椒幼苗的鲜质量和干质量不产生显著影响,而添加法中,EBR对辣椒幼苗鲜质量和干质量的影响没有规律性。     

猪骨骼肌卫星细胞中miR-24功能的初步研究及靶基因分析

为了探讨miR-24对猪骨骼肌发育的影响,对体外培养1日龄纯种长白公猪骨骼肌卫星细胞分别转染miR-24过表达载体和干扰片段,发现过表达miR-24后,成肌分化基因MyoD、Myogenin和Myf5表达量显著升高,骨骼肌卫星细胞分化趋势增强;干扰miR-24后,Myogenin的表达量显著降低;同时,靶基因预测结果显示Myogenin可能是miR-24的靶基因。     

Triterpenes and steroids from the leaves of Aglaia exima (Meliaceae)

A study on the leaves of Aglaia exima led to the isolation of one new and seven known compounds: six triterpenoids and two steroids. Their structures were elucidated and analyzed mainly by using spectroscopic methods; 1D and 2D NMR, mass spectrometry, UV spectrometry and X-ray. All the triterpenoids and steroids were measured in vitro for their cytotoxic activities against eight cancer cell lines; lung (A549), prostate (DU-145), skin (SK-MEL-5), pancreatic (BxPC-3), liver (Hep G2), colon (HT-29), breast (MCF-7) and (MDA-MB-231). The new cycloartane triterpenoid, 24(E)-cycloart-24-ene-26-ol-3-one 1, showed potent cytotoxic activity against colon (HT-29) cancer cell line (IC₅₀ 11.5 μM).     

嘧菌·己唑醇对水稻纹枯病室内抑菌活性与田间防治效果

室内毒力测定结果表明:嘧菌酯与己唑醇以2∶3、1∶2、1∶3配比均可,其中嘧菌酯与己唑醇以1∶2复配的制剂EC50为0.00791μg/mL,SR50为1.55。田间防效试验表明:24%嘧菌.己唑醇SC 375 mL/hm2、450 mL/hm2与24%噻呋酰胺SC 360mL/hm2,三处理之间差异不显著,但均与24%嘧菌·己唑醇SC 300 mL/hm2、10%己唑醇SC 750 mL/hm2、250 g/L嘧菌酯SC375 mL/hm2差异显著或极显著。24%嘧菌·己唑醇SC 375～450 mL/hm2(推荐用量)与24%噻呋酰胺SC 360 mL/hm2的防效相当,但成本低,性价比高,同时能兼治稻曲病、稻瘟病,达到一药多治效果,对水稻生育安全,无药害,且能使水稻叶片增绿,增强生长势等作用。     

高产小麦新品种“绵阳24号”的产量稳定性研究

本文主要用EberharL－Russell的模式方法分析了1995、1996年南方冬麦区西南片大区区试试验资料，结果表明“绵阳24号”产量极显著高于对照及其它品种，具有高产、稳产，综合性状好，适应性广等材性，属于平均型稳定性品种。     

“威24”大麦作肉猪饲料的饲用价值评定

本研究用体重20kg左右的长ｘ荣F1断奶仔猪56头,随机分为7组;以玉米、小麦对照,用“威24”大麦等量取代进行饲养试验和肉质测定。取代比例为：20～60kg阶段20％、40％、60％;60～90kg阶段25％、45％、65％直至90kg结束。同时测定了“威24”大麦的常规营养成分、部分微量元素、维生素和10种必需氨基酸含量,以及常舰营养成分和10种必需氨基酸的表观消化率。饲养试验及肉质测定结果显示：各组问增重速度、单位增重耗能和蛋白质均无显著差异（P＞0．05）;各组间屠宰率在70．30％～73．90％间,差异不显著（P＞0．05）;瘦肉率以60％大麦组最高,极显著高于玉米和小麦对照组（P＜0．01）,其他各级间无显著差异（P＞0．05）。     

苹果U-box型E3泛素连接酶MdPUB24的耐盐性和ABA敏感性鉴定

从‘皇家嘎拉’苹果(Malus×domestica Borkh.)中克隆了一个E3泛素连接酶基因(序列号:MDP0000199588)。基因序列测序发现,该基因包含长为1 212 bp完整的开放阅读框,编码404个氨基酸。系统进化树分析表明,这一E3泛素连接酶与拟南芥At PUB24同源序列相似性最高,因此将其命名为MdPUB24。利用Plant Care数据库进行启动子顺式作用元件预测分析表明,MdPUB24启动子序列中含有与脱落酸、光、茉莉酸及干旱信号相关的顺式作用元件。荧光定量PCR分析表明,MdPUB24在‘皇家嘎拉’苹果的不同组织中均有表达,且在叶片中最高;外源ABA、NaCl和低温胁迫处理能够抑制‘皇家嘎拉’苹果组培苗中MdPUB24的表达。MdPUB24过量表达的‘王林’苹果愈伤组织和异位表达的拟南芥幼苗在盐胁迫条件下,生长势与野生型相比明显变弱,表明MdPUB24负调控盐胁迫。相反,在外源ABA处理条件下,MdPUB24过量表达苹果愈伤和异位表达拟南芥与对照相比,生长势明显增强,表明MdPUB24对ABA不敏感。     

青花菜开花促进因子AGL19与整合子AGL24和SOC1的互作研究

为阐明青花菜(Brassica oleracea var.italica)开花促进因子AGL19与开花整合子AGL24和SOC1蛋白的互作机制,从青花菜中克隆了AGL19、SOC1及AGL24基因。它们分别编码221、221和214个氨基酸,均为MIKC型蛋白,并且与甘蓝、油菜、大白菜等亲缘关系较近,AGL19与SOC1同属TM3/SOC1亚家族成员。酵母双杂交表明:AGL19与AGL24蛋白能互作,激活酵母报告基因AUR1-C、HIS3、ADE2和MEL1,在QDO/X-α-Gal/Ab A平板培养基上长出蓝斑;但与SOC1蛋白不能相互作用,说明AGL19的直接靶蛋白是AGL24而非SOC1。此外,青花菜SOC1也能与AGL24蛋白互作,说明AGL19可以通过AGL24间接与SOC1相互作用。