Gene cloning of ZmMYB59 transcription factor in maize and its expression during seed germination in response to deep‐sowing and exogenous hormones

Discovering the key genes responsible for deep‐sowing germination is very meaningful to cultivate maize varieties with strong germination ability in soil. In this study, ZmMYB59 gene whose functions remain unknown was successfully cloned. Subcellular localization showed that ZmMYB59 was localized in the nucleus. By analysing cis‐acting elements of its promoter sequence, many elements of MYB binding domain responsive to hormones (particularly gibberellin, GA) were found. On this basis, ZmMYB59 expression in different sowing depths, germination stages, tissues and treatments was analysed by real‐time PCR. ZmMYB59 expression levels in embryos or seedlings were significantly decreased with the increase in sowing depth at 2 days or 4 days after sowing (DAS). Further analysis showed that its expression in mesocotyls was also significantly downregulated with the increase in sowing depth at both 6 DAS and 8 DAS. Similarly, seed soaking with 10^‐5 M GA₃ inhibited ZmMYB59 expression in mesocotyls at 3 DAS. These results suggest that ZmMYB59 may play a negative regulatory role in seed germination in deep soil and the regulation is involved in GA signalling pathway.     

Potential for the alleviation of arsenic toxicity in paddy rice using amorphous iron-(hydr)oxide amendments

Abstract

A pot culture experiment was conducted to investigate the effects of amorphous iron-(hydr)oxide (Am-FeOH) amendments on arsenic (As) availability and its uptake by rice (Oryza sativa L. cv. BR28) irrigated with As-contaminated water. A rhizobag system was established using 3.5 L plastic pots, each containing one central compartment for plant growth, a middle compartment and an outside compartment. Three levels of laboratory-synthesized Am-FeOH (0, 0.1 and 0.5% w/w) were used to amend samples of the As-free sandy loam paddy soil placed into each compartment of the rhizobag system. The soils were submerged with a solution containing 5 mg L^?1 As(V). Two-week-old rice seedlings were planted in the central compartments and cultured for 9 weeks under greenhouse conditions. The addition of 0.1% Am-FeOH to the soil irrigated with As-contaminated water improved plant growth, reduced the As concentration in the plants and enhanced Fe-plaque formation on the root surfaces. Analysis of soil solution samples collected during the experiment revealed higher pH levels and lower redox potentials in the soils amended with Am-FeOH at the onset of soil submergence, but later the soil solution collected from the 0.1% Am-FeOH treatment was slightly acidic and more oxidized than the solution from the 0% treatment. This indicated active functioning of the roots in the soil treated with 0.1% Am-FeOH. The concentrations of As(III) in the soil solution collected from the central compartment were significantly reduced by the Am-FeOH amendments, whereas in the soil treated with 0% Fe, As(III) accumulated in the rhizosphere, particularly during the late-cultivation period. The improvement in plant growth and reduction in As uptake by plants growing in the Am-FeOH treated soil could be attributed to the reduction of available As in the soil solution, mainly as a result of the binding of As to the Fe-plaque on the root surfaces.     

转人MCP和CD59双基因小鼠的制备

采用显微混合注射的方法制备转人MCP(膜辅因子蛋白)和CD59(膜反应性溶解抑制物)双基因小鼠,共注射478枚受精卵,移植于21只受体,其中14只受孕,8只受孕小鼠中途流产,从6只受孕小鼠获得18只仔鼠,经检测,其中9只仔鼠单基因阳性(50％),6只仔鼠双基因阳性(33．3％)。结果表明：通过显微混合注射的方法可以获得转人MCP和CD59双基因小鼠。     

仔猪产气荚膜梭菌肠毒血症病原诊断及疫苗研究IV．肠毒血症C型疫苗生产用菌种的确定

试验证明用单一菌株C59-2生产C型产气荚膜梭菌肠毒血症干粉灭活疫苗,其效力可以达到《规程》要求,并且简化了生产工艺,降低了生产成本,提高了生产效率。疫苗免疫的兔血清可分别中和原来3个制苗用菌株所产生的外毒素。     

Effect of supplied phytosiderophore on 59Fe absorption and translocation in Fe-deficient barley grown hydroponically in low phosphorus media

Hydroponically grown barley plants ( Hordeum vulgare L. cv. Minorimugi) under iron-deficient (–Fe) and high phosphorus (P) conditions (500 µmol L⁻¹) showed Fe chlorosis and lower growth compared with plants grown in –Fe and low P conditions (50, 5 and 0.5 µmol L⁻¹). To understand the physiological role of P in regulating the growth of plants in –Fe medium, we carried out an Fe feeding experiment using four P levels (500, 50, 5 and 0.5 µmol L⁻¹) and phytosiderophores (PS), mugineic acid. Our results suggest that plants grown in a high P medium had higher absorption activity of ⁵⁹Fe compared with plants grown in low P media, irrespective of the presence or absence of added PS. Translocation of ⁵⁹Fe from roots to shoots was not affected by the P level. The relative translocation rate of ⁵⁹Fe increased with decreasing levels of P in the medium. In general, the addition of PS enhanced the absorption of ⁵⁹Fe and its translocation. Taken together these results suggest that the lower relative translocation rate of Fe in high P plants may be induced by the physiological inactivation of Fe in the roots, and the higher absorption activity of Fe in high P conditions possibly results from the response of barley plants to Fe deficiency.     

Rare Chromones from a Fungal Mutant of the Marine-Derived Penicillium purpurogenum G59

Three new and rare chromones, named epiremisporine B (2), epiremisporine B1 (3) and isoconiochaetone C (4), along with three known remisporine B (1), coniochaetone A (5) and methyl 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate (6) were isolated from a mutant from the diethyl sulfate (DES) mutagenesis of a marine-derived Penicillium purpurogenum G59. The structures of 2–4 including the absolute configurations were determined by spectroscopic methods, especially by NMR analysis and electronic circular dichroism (ECD) experiments in conjunction with calculations. The absolute configuration of the known remisporine B (1) was determined for the first time. Compounds 2 and 3 have a rare feature that has only been reported in one example so far. The compounds 1–6 were evaluated for their cytotoxicity against several human cancer cell lines. The present work explored the great potential of our previous DES mutagenesis strategy for activating silent fungal pathways, which has accelerated the discovery of new bioactive compounds.     

DIFFERENTIAL TRANSLOCATION OF 59IRON IN IRON SUFFICIENT AND DEFICIENT SORGHUM PLANTS

Radioactively labeled iron (⁵⁹Fe) was used to study differential uptake in sorghum plants in the recovery stage of chlorosis. Radio-labeled ⁵⁹Fe was supplied through root feeding in nutrient solution experiment (48 hrs, pH 6.2) to non-chlorotic and chlorotic plants. Chlorotic plants were further treated with foliar spray [ferrous sulfate (FeSO₄), FeSO₄ + thiourea (TU), FeSO₄ + citric acid (CA), FeSO₄ + thioglycollic acid (TGA)] to study the uptake of radio-labeled ⁵⁹Fe through root feeding during recovery process of chlorosis. Under iron deficiency, the differential uptake of ⁵⁹Fe was markedly increased in leaves and stem of chlorotic control (-Fe) sorghum plants as compared to non-chlorotic control (+Fe) and foliar sprayed (FeSO₄, FeSO₄ + TU, FeSO₄ + CA, and FeSO₄ + TGA) plants. The lowest uptake of ⁵⁹Fe was observed in younger leaves (24.33 nmol, g^?1 fresh weight h^?1) and stem (1.98 nmol, g^?1 fresh weight h^?1) of non-chlorotic control followed by foliar sprayed plants in comparison to chlorotic control, respectively. Similarly less ⁵⁹Fe uptake was observed in the older leaves of FeSO₄ + CA sprayed (21.70 nmol, g^?1 fresh weight h^?1) plants in comparison to chlorotic control (35.60 nmol, g^?1 fresh weight h^?1). The highest differential ⁵⁹Fe uptake through nutrient medium was in the roots of plants, which were foliar sprayed with FeSO₄ along with TU. The role of iron alone and along with citric acid and thiol compounds is discussed in recovery of chlorosis.     

早熟高产优质抗病大豆新品种合农59选育与推广

为了选育适宜高寒地区种植的大豆品种,在1995-1998年种质创新的基础上,于1999年以合丰39为母本,合交98-1246(北丰11×ELF)为父本经有性杂交选育出大豆新品种合农59,2010年由黑龙江省农作物品种审定委员会审定推广。该品种生育日数113d,需≥10℃活动积温2 205.8℃,为早熟品种;区域试验平均产量2 627.0kg·hm-2,较对照品种宝丰7号增产10.4%;生产试验平均产量2 561.5kg·hm-2,较对照品种合丰51增产12.5%;蛋白质含量39.87%,脂肪含量20.64%;中抗灰斑病、抗花叶病毒病SMVⅠ号株系和中抗花叶病毒病SMVⅢ号株系;适宜北方春大豆早熟区种植;2010-2014年累计推广面积33.56万hm2,生产商品大豆8.6亿kg,创产值效益38.4亿元;增产大豆0.96亿kg,创社会效益4.3亿元。     

橡胶树优良品种热研7-20-59的选育

热研７－２０－５９是一个速生高产而相对晚熟的橡胶树优良无性系,在基本试区１～９割年干胶产量逐年递增,第９割年平均年产干胶为５．７９ｋｇ／株,２０５７ｋｇ／ｈｍ＾２,分别比对照ＰＲ１０７增产８６．８％和７３．４％;头９割年平均年产干胶３．９５ｋｇ株,１４６７ｋｇ／ｈｍ＾２,分别为对照的１７８．７％和１６８．６％。此外,该品种抗能力较强,风害后有较强的恢复生长能力。在海南农垦１９９８年橡胶树优良品种汇     

精子介导生产转hCD59基因猪

为研究精子介导法生产异种器官移植用转基因猪的效率,将人膜反应性溶解抑制物(hCD59)基因与脂质体混合制成基因/脂质体复合物,分别采用睾丸注射法和基因脂质体复合物/精子共孵育法制备转人hCD59基因猪,其中睾丸注射法处理公猪1头,44 d后配母猪8头,7头受孕(受孕率87.5%),产仔73头,PCR阳性猪3头(阳性率4.3%);外源基因/精子共孵育法处理公猪4头,处理母猪4头,1头受孕(受孕率25%),产仔11头,PCR阳性猪1头(阳性率9%)。从15头受孕母猪共获得84只仔猪,经PCR初步检测,其中4只仔猪为转基因阳性,阳性率4.8%。研究结果表明:通过精子介导法可以获得转基因猪。