The structural and histochemical changes of the egg apparatus in the polyembryonic rice (Oryza sativa L.), ApⅢ with the highest frequence of additional embryos among the polyembryonic rice investigated, before and after fertilization were studied and compared with those of normal and other polyembryonic rices in a similar developmental period. A total of 2 932 ovules were observed and each of them contained only asingle embryo sac with a set of egg apparatus. Among 1 655 embryo sacs, there were 1 643 embryo sacs (99.27%) with one normal egg apparatus in each embryo sac, and only 12 embryo sacs (0.73%) from the remainder with 4 celled egg apparatus, i.e. two eggs and two synergids. Neither the numerous poly egg apparatus and egg like cells, nor the double set of embryo sacs each containing one egg apparatus and other abnormal egg apparatus in single ovary, which were reported by earlier investigators to have high frequency of embryo production in SB 1 and ApⅣ, were observed. The egg cell was located at the subterminal site of the micropylar end of embryo sac. The cytoplasm of egg cell was rich in protein materials and poly saccharide grains, which did not disappear until the division of zygote. The prominent nucleus was closely surrounded by protein and polysaccharide grains, which did not disappear until the division of zygote. No cytological difference was found between egg cells from the normal and abnormal egg apparatus. The two synergids were fully developed and situated at the upper most part of the micropylar end of the mature embryo sac. In most embryo sacs, the synergids were flask shaped with longer necks, and a widened cap shaped top, in close contact with the micropyle. The synergids had a well developed filiform apparatus. The characteristic appearance of the filiform apparatus as well as the cap neck region of synergids before and after pollen tube penetration were easily distinguishable from the egg cell. The structure, the stainability with Coomassie Brilliant Blue and PAS reaction, the process of accumulation, distribution and disapperance of the cytoplasmic protein materials and polysaccharide grains of the two synergids, the persistent and rarely the receptive synergids before and after pollen tube penetration, were closely similar to those of egg cell of the same developmental stage. In comparison with normal and other polyembryonic rice reported, the size of nucleus and nucleolus and their stainability also strongly resembled those of egg cell. Based on the results observed, the main conclusions are summarized as follows: (1) the additional embryos very frequently developed in the young and mature seed of polyembryonic rice ApⅢ were produced by one or two synergids of normal egg apparatus, rarely by 4 celled egg apparatus; (2) during fertilization, the synergids, in addition to the natural specific function of introducing pollen tube and transferring sperms to egg cell and central cell, could be closely associated with the potentiality to breed one or two additional embryos; and (3) as compared with that of normal or other polyembryonic rice it is firstly disclosed that in a few embryo sacs of ApⅢ, the cytoplasmic and nuclear structure, the active anabolism and catabolism of protein and polysaccharide materials and the delayed disorganization at the mid basal region of the receptive and persistent synergid still remained unchanged before the division of zygote. Such salient features could be the predisposition for the origin of additional embryos in ApⅢ.
母锡金 朱至清 蔡 雪 孙德兰 林金星*
摘要： 对高频率多胚水稻（Oryza satixa L）ApIII受精前后卵器的细胞结构和组织化学变化进行了观察，并同已报道的正常水稻和多胚水稻大至相同发育时期的卵器进行了比较，结果表明：ApIII的23932 个幼嫩子房中，每个子房只有一个胚囊。没有看到含有一对胚囊和每个胚囊里有一套卵器的现象。除解体的和含胚的胚囊外，1655个胚囊中，含1 个卵细胞和2个助细胞组成的正常卵器为1643 个（99.27% ），含2个卵细胞和2 个助细胞的4细胞卵器为12 个（0.73%）。没有观察到大量4细胞卵器、5细胞卵器（即由3 个卵细胞和2 个助细胞组成）和卵状细胞，以及其他4卵、5 卵卵器的变异类型。卵细胞位于对着子房壁维管束一侧。细胞质含丰富的蛋白质和多糖颗粒；细胞核位于细胞中下部，少有偏远轴端的，直到合子分裂前由蛋白质物质和多糖颗粒聚成的环所包裹。成熟胚囊中常见2 个助细胞。助细胞位于珠孔端靠子房壁维管束一侧，多数为长颈烧瓶状，少有长形和星月形的。其珠孔端壁内侧丝状器发达，细胞质的结构，蛋白质物质和多糖颗粒的积累、分布及消长，细胞核的大小、组织化学反应和周围物质的动态与卵细胞的相同。此外，ApIII 的２个助细胞存留时间较长。当花粉管进入助细胞的早期，助细胞的丝状器和帽颈端被花粉管损伤，中下部细胞质和核所在区仍保持完好。由以上结果得出结论：多胚水ApIII高频率的额外胚（１ 或２ 个）主要来自3 细胞正常卵器，极少来源于4细胞卵器；ApIII 的助细胞除在受精和胚胎发生早期具特殊功能外，与卵细胞相似的细胞质结构、物质代谢过程以及崩溃较晚可能与胚胎发生有关；在ApIII 的少数胚囊中，接受助细胞可能有发生胚的潜能。
Ultrastructural features of nucleus degradation during programmed cell death (PCD) of starchy endosperm cells in rice (Oryza sativa L.) were observed using transmission electron microscopy. Several distinct morphological features of PCD have been found in the developing starchy endosperm cells, e.g. nucleus deformation, chromatin condensation, nuclear envelope disruption, and nuclear matrix leakage. DNA ladder displayed a smear of large DNA fragments from nucleus and evident bands of small DNA fragments (140-180 bp) from both nucleus and cytoplasm. In contrast with the rapid nucleus degradation, cell organelles in cytoplasm, such as rough endoplasmic reticulum, a myloplast, and mitochondrion, maintained their metabolic functions for a longer time. Seed reserves were continually synthesized and accumulated in the starchy endosperm cells despite the nucleus degradation during the PCD process. These results suggest that starchy endosperm cells remain active during reserve material synthesis and accumulation in the PCD process. The specific relationships between nucleus and cytoplasm in the developing endosperm cells and the morphological changes of nucleus in the endosperm PCD process were also discussed.
韦存虚 蓝盛银* 徐珍秀
摘要： 应用透射电子显微镜技术,观察了水稻(Oryza sativa L.)淀粉胚乳细胞编程性死亡过程中核的变化特征.伴随胚乳的发育进程,淀粉胚乳细胞核表现出衰退特征:核变形、染色质凝缩、核膜多处被降解破坏、核基质外泄等.DNA Ladder显示核内大片段DNA呈严重的弥散状拖尾现象,而核内和胞质中在140～180 bp处有明显的条带.在核衰退的同时,其胞质中的粗面内质网、淀粉质体和线粒体等细胞器具有正常的代谢功能,细胞仍在合成并积累营养物质,淀粉胚乳细胞一边衰退一边行使其功能,直至死亡.这些结果表明,水稻淀粉胚乳在核衰退的同时,细胞仍在积极合成与积累贮藏产物,表现为一种特殊形式的植物细胞编程性死亡现象.此外,对淀粉胚乳细胞特有的核质关系、植物细胞编程性死亡过程中细胞核的变化等问题进行了讨论.
One of the prominent cell cycle related modifications of histone proteins, whose function is correlated with chromosome condensation, is the phosphorylation of histone H3. Wheat (Triticum aestivumL.) mitotic and meiotic cells were analyzed with indirect immunoflurorescence labeling with an antibody recognizing histone H3 phosphorylated at Serine 10 to study the localization of phosphorylated histone H3 at mitosis and meiosis. Our results showed that, during mitotic division, the phosphorylation of H3 started from early prophase and vanished at telophase, remaining mainly in the pericentromeric regions at metaphase and anaphase. During meiotic division, phosphorylation of H3 initiated at the transition from leptotene to zygotene and remained uniform, along the chromosomes from prophase Ⅰ until telophase Ⅰ, whereas it showed slightly stronger in the pericentromeric regions than along the chromosome arms from metaphase Ⅱ until telophase Ⅱ.The different patterns of H3 phophorylation at mitosis and meiosis in wheat suggested that this evolutionarily conserved post translational chromatin modification might be involved in more roles besides chromosome condensation.
杨 琴 黄熙泰* 耿朝晖 俞新大
摘要： 在细胞周期中 ,与染色质凝集偶联的一类组蛋白修饰是组蛋白H3的磷酸化。运用H3－Ser 10磷酸化的特异性抗体 ,通过间接免疫荧光标记检测了磷酸化组蛋白H3在小麦 (Triticumaestivum L .)有丝分裂与减数分裂细胞中的分布。有丝分裂时 ,H3磷酸化起始于早前期 ,消失于末期 ,在中期与后期 ,H3磷酸化主要分布在着丝粒两侧的异染色质区。减数分裂时 ,H3磷酸化起始于细线期向偶线期转换时 ,并且从前期Ⅰ到后期Ⅰ保持均一分布于整个染色体上 ,直到末期Ⅰ消失 ,而中期Ⅱ与后期Ⅱ在着丝粒两侧的异染色质区的信号略强于染色体臂 ,直至消失于末期Ⅱ。磷酸化组蛋白H3在两类细胞分裂中的不同分布暗示这种保守的翻译后修饰可能发挥着除参与染色体凝集外的更复杂的作用。
关键词： 小麦；有丝分裂；减数分裂；组蛋白%! 磷酸化；免疫荧光标记
通讯作者。Ｔel; +86 (0)22 23508874. E-mail: xthuang @ public.tpt.tj.cn
The mechanism of the proton transfer coupled electron transfer (PT-ET) reactions between the menaquinone QA (MQ1) and ubiquinone QB (UQ1) in the bacterial photosynthetic reaction center of Rhodopseudomona viridis was studied by using the B3LYP/6-31G(d) method. The changes of standard Gibbs free energy ΔG0 of all possible reactions followed the ET reaction (1) were calculated. The results indicated that: (1) according to the ΔG0 values of corresponding reactions, UQ1 could not accept two electrons from MQ-1 continually without the coupled proton transfer reactions. Because of ΔG0 2b0, ΔG0 3b0 and ΔG04b0, the corresponding PT ET reactions could take place along with reactions (2b), (3b) and (4b) equentially; (2) on the gaseous condition, the first and second transferred protons (H+(1) and H+(2)) from the surrounding amino acid residues or water molecules will combine with the oxygen No.7 and oxygen No.8 of UQ1, respectively. On the condition of protein surroundings (by SCRF model,ε=4.0), the results are converse but the energy difference between the combination of H+(1) and H+(2) with UQ-1 is quite small. The difference of ΔG0 values between the corresponding reactions in gaseous surroundings and the SCRF model is not significant; (3) the PT ET reactions between MQ1-and UQ1-should be as follows: MQ1-+UQ1→MQ1+UQ1- (1) UQ1-(O(7)+H+(HisL190) →UQ1H (2b)(Gas) or UQ1－(O(8))+H+(H2O)→UQ1H (2b') (SCRF) or UQ1－(O(8))+H+ (ArgL217)→UQ1H (2b')(SCRF) MQ－+UQ1H→MQ1+UQ1H- (3b)(Gas) MQ1－+UQ1H→Q1+UQ1H- (3b') (SCRF) UQ1H-+H+(H2O)→UQ1H2 (4b)(Gas) or UQ1H－+H+ (ArgL217)→UQ1H2 (4b) (Gas) or UQ1H－+H+ (HisL190)→UQ1H2 (4b') (SCRF)
Rhodopseudomena viridis 细菌光合作用反应中心质体醌QA与泛醌QB间电子转移耦合质子转移机理的理论研究
马淑华 徐 红 张汝波 屈正旺 张兴康 张启元*
摘要：用量子化学B3LYP/ 6 - 31G(d)方法 ,对Rhodopseudomenaviridis细菌光合反应中心质体醌QA(MQ1)与泛醌QB(UQ1)间的电子转移耦合质子转移 (PT－ET)机理进行了研究。对反应 (1)之后的Gibbs自由能变化进行了计算。结果表明 ,(1)按照各反应的数值 ,在无耦合质子转移的情况下 ,UQ1不可能由MQ1－连续接受两个电子。由于ΔG02b 0 ,ΔG03b 0和ΔG04b 0 ,相应的PT ET反应将依序沿 (2b)、(3b)及 (4b)进行。 (2 )在气相情况下 ,由于周围的氨基酸残基或水分子转移到UQ1的第一个及第二个质子 (H+ (1)和H+ (2 ) )将先后分别与UQ1的No.7和No .8氧原子结合 ;在蛋白环境情况下 (SCRF方法 ,ε =4 .0 ) ,质子耦合的顺序正相反 ,但H+ (1)和H+ (2 )与UQ-1结合的能量传递差很小。在气相及SCRF模拟环境中 ,相同反应间的ΔG0 无显著差别。 (3)MQ-1间UQ-1的PT ET反应如下 : MQ1-+UQ1→MQ1+UQ1-(1) UQ1-(O( 7) ) +H+ (HisL190 )→UQ1H (2b) (Gas)or UQ1-(O( 8) ) +H+ (H2 O)→UQ1H (2b’) (SCRF)or UQ1-(O( 8) ) +H+ (ArgL2 17)→UQ1H (2b’) (SCRF) MQ1-+UQ1H→MQ1+UQ1H-(3b) (Gas) MQ1-+UQ1H→MQ1+UQ1H-(3b’) (SCRF) UQ1H-+H+ (H2 O)→UQ1H2 (4b) (Gas)or UQ1H-+H+ (ArgL2 17)→UQ1H2 (4b ) (Gas)or UQ1H-+H+ (HisL 190) →UQ1H2(4b ’)(SCRF)
关键词： Rhodopseudomena viridis ；电子转移；质子转移；QA和QB；DFT
通讯作者。Fax:+86 (0) 10 62588930;E-mail: zhangqy @ infoc3.icas.ac.cn.
Radial variation in sap flux density (SFD) as a function of sapwood thickness is of importance in accurately estimating sap flux through sapwood area which, inturn, decides the precision of heat pulse application. However, until now, only a few studies have evaluated the magnitude and significance of sampling errors asociated with radial gradients in SFD, which were based on the small monitoring measurement data from a few trees. Based on one year of heat pulse observation of two 3-4 years old Eucalyptus urophylla S.T. Blake plantations in Leizhou Peninsula, Guangdong Province, China, a way of data processing was developed to treat with the lots of SFD data measured from 39 trees. It was found that the radial variation in SFD as a function of sapwood thickness in the two eucalyptus plantation sites could be expressed as y=3.667 5x3-7.295 5x2+3.682 6x+0.567 4 (R2=0.939 1, n=80, P=0.01), where y is the ratio of SFD of a sensor to the average of four data in different depths, x is the ratio of a sensor depth to the radial sapwood thickness. It was the same (as in the following equation) in Jijia site, y=5.006 2x3-9.116 1x2+4.454 4x+0.463 4 (R2=0.806 9, n=72, P=0.01) in Hetou site. From cambium to heartwood, SFD showed some increases at first and then decreases continuously. However, because the trees were very young, the maximum SFD was only 0.33-0.36 times more than the minimum.
周国逸1* 黄志宏1 Jim MORRIS2 李志安1 John COLLORY2 张宁南3 白嘉雨3
（1. 中国科学院华南植物研究所，广州510650；Centre for Fprest Tree Technology,Victoria 3084, Australia; 3. 中国林业科学院热带林业研究所，广州510520）
摘要： 树液流动密度(SFD)随边材径向深度的变化对于准确估测流经边材的树液通量是非常重要的,后者又制约着Heat Pulse的应用精度.但迄今为止,只有很少的研究估计了由于SFD随径向的梯度变化而带来的误差,SFD沿树干径向分布规律的获得往往依靠对少数几棵树的观测资料.基于在广东雷州半岛对两块3～4年生桉树(Eucalyptus urophylla S.T. Blake)人工林1年的Heat Pulse观测,探讨了对来自39株立木大量观测资料的综合处理方法,发现这两个样地(纪家和河头)的林分中SFD随边材径向深度的变化可以用如下回归方程来描述:纪家: y=3.667 5x 3-7.295 5x2+3.682 6x+0.567 4 (R2=0.939 1, n=80, P=0.01)河头: y=5.006 2x 3-9.116 1x2+4.454 4x+0.463 4 (R2=0.806 9, n=72, P=0.01)式中:y--某一树液感应器所测得的SFD与不同深度的4个感应器所测得的SFD的平均值之比;x-某一树液感应器在边材中的深度与边材厚度之比.从形成层到心材,SFD最初有所增加,随后持续减小,但由于树木年龄很小,最大的SFD只比最小的SFD大0.33～0.36倍.
The response of subterranean clover (Trifolium subterraneum L.) to different abscisic acid (ABA) concentrations (10-6, 10-5, 10-4 mol/L) in nutrient solution and to water stress were studied in growth room. Six cultivars of contrasting yield capacity were compared. Plants remained growing in Hoagland solution or pots until at least four full developed leaves appeared. The ABA was then applied and the fresh weight, leaf number and length of the largest root were measured at 1, 4, 7 and 11 d after ABA treatment. The above parameters were also measured at 15 d under water stress. In all the tested genotypes ABA caused similar reduction in these growth parameters, as well as a significant decrease of leaf water potential which was dependent on ABA concentration. The average growth reduction after 11 d under 10－4 mol/L ABA coincided with the range of these crops under water stress in pot experiments.On average of the different genotypes, leaf number, area of full developed leaf and the dry weight per plant decreased by about 50% whereas the root/shoot ratio increased by 80%.The genotype variation and ranking for this treatment were rather similar to the same genotypes in pot experiments. The genotypes, Clare, Nuba and Seaton Park, showed the best results under both control and ABA treated conditions and water stress conditions. The similarity between the response to ABA in nutrient solution and to water stress opens the possibility to use this approach as a way to quantify the drought resistance of subterranean clover genotypes.
许 兴1,3* 郑国琦2 邓西平3 Hipolito MEDRANO 4
（1. 宁夏农业生物技术重点实验室，银川750002；2. 宁夏大学生命科学学院，永宁750105；3. 中国科学院水利部水土保持研究所，杨凌712100;4. Department de Biologia, Instituto Mediterraneo de EstudiosAvanzados (UIBCSIC),Universitat de Les illes Balears,Carretera Valldemossa Km.7,5;07071 Palma de Mallorca,Baleares,Spain
摘要： 在室内研究了不同浓度外源ABA处理和不同水分胁迫对 6种不同基因型的三叶草 (TrifoliumsubterraneumL .)生长的影响。当三叶草的第四片叶完全展开时 ,向营养液中施加不同浓度的ABA时对盆栽土壤进行控水。在处理的 1,4 ,7和 11d ,测定植株鲜重、叶片数、最长根长 ,以表示三叶草的生长状况。各参试品种以上三项生长指标均受外源ABA和水分胁迫的影响而呈现下降的趋势。同时 ,叶片水势值随ABA浓度的增加和水分胁迫强度的增加而明显降低。在 10 -4 mol/LABA处理 11d后 ,参试品种平均生长量的减少与水分胁迫 15d后其生长量的减少的结论一致。在不同浓度ABA处理下 ,不同基因型三叶草平均叶片数 ,完全展开叶面积和每株干物质重约降低了5 0 % ,而其根冠比却增加了 80 %。不同基因型三叶草生长参数间的变化及排序结果与盆栽相同品种获得的实验结果非常相似。品种Clare、Nuba和SeatonPark在对照和处理下均表现最好。由于三叶草对一定浓度范围的外源ABA的反应与其在盆栽水分胁迫下的反应结果十分相似 ,因此 ,利用外源ABA处理的方法来研究不同基因型三叶草的耐旱性将可能是一种行之有效的方法。
Abscisic acid (ABA) plays an important role in plant growth and developmental processes. Although some ABA signal molecules, such as cADPR, Ca2+, etc., have been reported, therewas no evidence proving the involvement of cAMP in ABA signal transduction. In this present study, the constructed gene (rd29A GUS ) was transformed into Nicotiana tabacum, and calli was induced from the transgenic plant. The suspension cells obtained from the callus grew well and uniformly. Treatment of the suspension cells with ABA led to an increase in GUS activity, indicating that these transgenic suspension cells are useful for the study of ABA signaling. Addition of nicotinamide (cADPR inhibitor) or U73122(phospholiphase C inhibitor) could only partially inhibit the increase of GUS activity elicited by ABA. The inhibitory effect of nicotinamide was enhanced by application of K252a (inhibitor of protein kinase). Treatment of the suspension cells with 8-Br-cAMP, a membrane permeable analogue of cAMP, could partially replace the effect of ABA. Furthermore, intracellular addition of IBMX (phosphodiesterase inhibitor) mimicked the effect of exogenous cAMP on the deduction of expression of rd29A promoter. These results suggested that cAMP was an important messenger in ABA signal transduction in tobacco suspension cell.
刘 璞 孟令军 张会霞 陈 珈* 王学臣
摘要： ABA诱导型启动子( rd29A)重组到报告基因(GUS)的上游构建表达载体.通过农杆菌介导转化烟草,获得转基因植株.将转基因植株诱导愈伤组织,建立稳定、均一的转rd29A-GUS融合基因的悬浮培养细胞系.用ABA处理悬浮细胞24 h后GUS活性显著升高,说明外源ABA能够诱导rd29A启动子的表达,获得了用于ABA信号转导研究的实用细胞系.在ABA激活表达的细胞介质中加入尼克酰胺(cADPR合成酶的抑制剂)或U73122(PLC抑制剂)只能部分抑制ABA的效应,但如果加入蛋白激酶抑制剂K252a,抑制效果达95%以上.用可跨膜的cAMP的类似物8-Br-cAMP处理细胞发现,它能代替ABA的作用;当介质中加入1 mmol/L IBMX(磷酸二酯酶的抑制剂)增加cAMP的稳定性,发现低浓度的8-Br-cAMP与ABA相同的效应.以上结果表明cAMP参与了烟草悬浮细胞中ABA信号的传递.
Reverse transcription Polymerase Chain Reaction (RT-PCR) was performed using cDNAs as templates from wheat Haynaldia villosa 6VS/6AL translocationline and “Yangmai 5" induced with fungus Erysiphe graminis, and degenerate primers designed based on the conserved amino acid sequences of known plant disease resistance genes. The cDNA sequences encoding cyclophilin like and H+ ATPase like genes were first isolated and characterized in wheat. The putative amino acid sequences of the two clones showed that they were highly homologous to those of cyclophilin proteins and H+ ATPases isolated from other plants. Thus they were designated as Ta-Cyp and Ta-MAH. The obvious expression differences could be observed between wheat H. villosa 6VS/6AL translocation line and susceptible wheat cultivar “Yangmai 5", implying that the two genes may be related with the resistance of wheat H. villosa 6VS/6AL translocation line to disease. Southern blot indicated that the wheat genome contained 2-3 copies of Ta-Cyp gene and one copy of the Ta MAH gene. Chinese Spring nulli tetrasomic line analysis located the Ta-Cyp homologous genes on wheat chromosome 6A, 6B and 6D. Southern blot using Ta-Cyp clone as a probe showed that the polymorphic bands existed among the H. villosa, amphiploid of Triticum durum H. villosa, wheat H. villosa 6VS/6AL translocation line and “Yangmai 5", suggesting that Ta-Cyp homologies exist in wheat genome as well as on the short arm of chromosome 6V in H. villosa.
于 玲* 牛吉山** 马正强 陈佩度*** 齐莉莉 刘大钧
摘要： 根据抗病基因保守结构域设计简并性引物,以被白粉菌(Erysiphe graminis)诱导后的小麦-簇毛麦6VS/6AL易位系和"扬麦5号"cDNA为模板进行反转录PCR(Reverse-transcription Polymerase Chain Reaction, RT-PCR)筛选,从小麦(Triticum aestivum Linn.)中分离到2个cDNA片段.蛋白质一级结构分析表明,它们分别与植物中已分离的cyclophilin蛋白和H+-ATP酶高度同源,将小麦中这2个基因分别定名为:Ta-Cyp 和Ta-MAH.经Northern杂交分析表明,这2个基因在抗病的小麦-簇毛麦6VS/6AL易位系及感病"扬麦5号"中的表达水平有一定差异,因此推断这2个基因有可能与小麦-簇毛麦6VS/6AL易位系的抗病性相关.Southern杂交发现Ta-Cyp基因在小麦基因组中的拷贝数为2-3个,Ta-MAH为单拷贝.利用中国春缺体-四体系,已将Ta-Cyp基因定位在小麦6A、6B及6D染色体上.用Ta-Cyp作探针,Southern杂交显示在簇毛麦、硬粒小麦-簇毛麦双二倍体、小麦-簇毛麦6VS/6AL易位系与"扬麦5号"之间表现多态,表明小麦基因组和簇毛麦染色体6VS上有其同源基因.
关键词： 克隆；小麦Z簇毛麦6VS/6AL易位系;cyclophilin 基因；H+-ATP酶基因
通讯作者。E-mail: pdchen @ njau.edu.cn
Metallothionein gene (MT) has been transferred into mushroom protoplasts by electroporation. It is a low molecular weight, cysteine rich and metal binding protein. MT can bind metals. Its synthesis is induced by Zn ion. Thus the express ion of MT gene in mushroom can improve the accumulation of Zn in this fungus. This transgenic mushroom, consumed as a kind of vegetable, can supply the necessary Zn to people who are short of the element. When protoplasts were prepared, the concentration (C)of protoplasts is 6.745×106 /mL. After protoplast electroporation, the transformation rate of protoplasts is 0.01%. Polymerase chain reaction (PCR) analysis showed that the gene had been integrated into the mushroom chromosome. SDS-PAGE, Western-blot analysis indicated that the MT gene had been expressed in the transgenic mushroom. The expressing level, detected by ELISA, is 0.6%-0.8%. Tested for metal resistance, the wild type mushroom growth was inhibited on the medium containing 1.0-1.2 mmol/L ZnSO 4. While the transgenic mushroom was inhibited on the medium containing 1.5-2.0 mmol/L ZnSO4. The mycelium can develop into hymenophore in the medium of rice bran∶sawdust =1∶3, and not in the medium of rice bran∶sawdust =1∶4.
张 竞 聂思惟 单 龙 茹炳根*
摘要： 将MT基因用电击法转化平菇 (Pleurotusostreatus) ,MT基因表达蛋白与金属离子结合而形成络合物 ,用Zn诱导 ,转基因平菇能富集Zn ,可为缺Zn的人群补充Zn ,使平菇成为一种保健和治疗的食品或蔬菜。原生质体制备浓度为 6 .74 5× 10 6个 /mL。原生质体电击转化率为 0 .0 1%。PCR检测 ,2 0 0bp处有MT基因条带。蛋白检测 :转基因MT平菇ELISA检测阳性 ,表达率为 0 .6 %～ 0 .8%。SDS－PAGE显示有表达条带。Westernblot显示有阳性条带。抗ZnSO4结果 :野生型平菇抗ZnSO4浓度为 1.0mmol/L ,1.2mmol/L开始受抑制 ,转基因平菇抗ZnSO4浓度为 1.5mmol/L ,2 .0mmol/L开始受抑制。出菇试验结果表明 ,在米糠与锯沫比为 1∶3的培养基上生长 ,在米糠与锯沫比为1∶4的培养基上不生长。 2 4d菌丝可在广口瓶中长满 ,用用于子实体培养。
通讯作者。Ｔel: + 86 (0) 10 62751842; E-mail: <rulab @ pku.deu.cn>
A 1 886 bp full length sesquiterpene synthase (AaSES) cDNA was cloned from a high yield Artemisia annua L. strain 001 by a rapid amplification of cDNA end (RACE) strategy. AaSES is 59% identical to Artemisia cyclase cDNA clone cASC125, 50% identical to epicedrol synthase from A. annua, 48% identical to amorpha 4, 11 diene synthase from A. annua, 39% identical to the 5 epiaristolechene synthase from tabacco, 38% identical to vetispiradiene synthase from H. muticus, 41% identical to the δ cadinene synthase from cotton. The coding region of the cDNA was inserted into a procaryotic expression vector pET 30a and overexpressed in E. coli BL21(DE3). The yclase proteins extracted from bacterial culture were found largely in an insoluble protein fraction. AaSES expresses in leaves, stems and flowers, not in roots as indicated by Northern blotting analysis.
刘 彦 叶和春* 李国凤
摘要： 用RACE方法从青蒿 (Artemisiaannua L .)高产株系 0 0 1中克隆了一个新的 1886bp的全长倍半萜合酶cDNA。克隆的倍半萜合酶氨基酸序列与烟草马兜铃烯合酶、莨菪岩兰螺旋二烯合酶、棉花杜松烯合酶的一致性分别为 39%、38%和 4 1% ;与青蒿柏木脑合酶、紫穗槐二烯合酶和一个推测的倍半萜合酶克隆cASC12 5的一致性为5 0 %、4 8%和 5 9%。cDNA编码区序列被克隆进原核表达载体pET-30a,并在大肠杆菌 (Escherichiacoli)BL2 1(DE3)中诱导表达 ,但过量表达的蛋白主要是以不溶性蛋白形式存在。Northernblotting分析表明此基因在茎、叶和花中表达 ,在根中没有表达。
通讯作者。电话：+86（0）10 62591431-6249；E-mail: <hcye @ ns.ibcas.ac.cn>
Pea (Pisum sativum Linn.) actin gene family contains at least three isoforms(PEAcⅠ, PEAcⅡand PEAcⅢ), and the DNA sequence of these isoforms show high similarity in the coding regions and significant divergence in the untranslated regions. RT-PCR and Southern blotting using 3′-untranslated region (3′-UTR) as specific probe revealed that pea isoactin genes were expressed in roots, stems, leaves, tendrils, pollen and juvenile siliques, but displayed different patterns of transcript accumulation. Two fold serial dilution electrophoresis showed PEAcⅠ mRNA preferentially accumulated in rapidly developing tissues: it peaked in seven days' stem; remained at a rather high level in leaves within a month but decreased sign ificantly later; varied a little in tendrils and reached a median and a very low level respectively in juvenile siliques and in pollen. PEAcⅡ displayed somewhat similar expression pattern to PEAcⅠ. The observed differences in sequences and transcript accumulation patterns suggest that the individual pea actin genes may differ in their transcriptional regulation and cellular function. Phylogenetic tree of actins showed that pea actin isoforms are as diverged from each other as they are from other plant actins, and pea actins might have originated from a common ancestor before the divergence of the dicot and monocot plants.
摘要： 豌豆 (Pisum sativum Linn .)肌动蛋白基因至少可以分为 3类异型体 :PEAcⅠ、PEAcⅡ和PEAcⅢ ,它们的编码区序列相似性很高 ,而非编码区序列存在显著的差异。RT_PCR和以 3′端非翻译区作探针的Southern杂交结果显示豌豆肌动蛋白异型体基因在根、茎、叶、卷须、花粉和幼嫩果实中均表达 ,但表达强度存在明显差异。利用连续稀释电泳对PEAcⅠ的转录本水平进行分析后发现它倾向于在幼嫩的器官中表达 ,且在 7d的茎中表达最强 ;在一个月内的叶片中表达也较强 ,此后明显下降 ;卷须中表达变化不显著 ,在花粉中表达很弱 ,在幼嫩荚果中的表达亦较多。PEAcⅡ表达特点与PEAcⅠ具有某些相似性。根据肌动蛋白序列重建的系统发生树表明豌豆肌动蛋白 3类异型体间的分歧明显 ,但起源于单、双子叶植物分化前的共同基因祖先。推测豌豆肌动蛋白异型体基因在转录调控和细胞功能上存在差异。
通讯作者。Tel: + 86 (0) 10 62892672;Fax:+ 86 (0)10 62891332
Phylogenetic relationships of the “higher" hamamelids were estimated based on nucleotide sequences of the non coding region of chloroplast trnL-F. Twenty-five species were sampled, representing 24 genera of all eight families of the “higher" hamamelids. A parsimony analysis of data set indicated that the “higher" hamamelids formed a strongly supported clade with 100% bootstrap value in the strict consensus tree. Nothofagus was the basal lineage and the Fagaceae was sister to a well supported core “higher" hamamelids clade containing Myricaceae, Rhoipteleaceae, Juglandaceae, Casuarinaceae, Ticodendraceae and Betulaceae. Three clades were recognized in the core“higher" hamamelids:(1)Casuarina (Ticodendron,(Betulaceae)), (2) Juglandaceae Rhoipteleaceae, and (3) Myricaceae. Compared with the previous studies, familial relationships of the “higher" hamamelids were better resolved.
据叶绿体trn L-F 序列分析“高等”金缕梅类植物的系统发育关系
李睿琦 陈之端* 洪亚平** 路安民
摘要: 研究对"高等"金缕梅类的8科24属25种植物和外类群Hamamelis两种植物的叶绿体DNA trnL-F区进行了测序,并根据DNA序列对该类植物的系统发育关系进行了分析.结果表明: 所有"高等"金缕梅类植物的科结合成一支, bootstrap 分析支持率为100%,各科之间的关系得到很好分辨.Nothofagus是最基部的一支;山毛榉科(Fagaceae)作为姐妹群与"核心"金缕梅类的科(桦木科Betulaceae,胡桃科Juglandaceae, 木麻黄科Casuarinaceae, 杨梅科Myricaceae, Ticodendraceae 和马尾树科Rhoipteleaceae)组成一支,并得到很强的支持."核心"金缕梅类构成三支,关系如下:(1) Casuarina (Ticodendron, (Betulaceae)), (2) Juglandaceae-Rhoipteleaceae, (3) Myricaceae.本研究显示叶绿体DNA trnL-F区对分辨"高等"金缕梅类科间关系及部分科内的属间关系十分有效.
关键词： trn L-F 区；叶绿体DNA；“高等”金缕梅类；系统发育关系
通讯作者。E-mail: zhiduan @ ns.ibcas.cn
The dimension, water content and germination of the seeds from 90 woody species in the lower subtropical forest were analyzed in this study. Out of 90 species, germination analysis was performed in 45 species (in which there were enough germinating individuals), and the effect of storage of seed and fruit on germination of seed was studied in 41 species (in which there were enough seeds and germinating individuals). Most of the species began to germinate within 60 d. Hypogeal species had longer dormancy than epigeal species. Dormancy of fleshy seeds and seeds in pulpy fruit was also longer than that of dry seeds. There were no significant differences in length of dormancy (LD, days from sowing to germination) between fleshy seeds ripening in summer and those ripening in winter and spring, and between big seeds and small seeds. Seeds in pulpy fruit or fleshy seeds had more germination than the dry seeds (P<0.05), however, percentage germination was not significantly correlated with water content of fresh seeds. Water loss in the seeds could obviously affect percentage germination, especially during the early three days when the seeds were laid open in air in the laboratory. When water content of the seeds decreased to about 20% (fresh weight basis), percentage germination became very low, this happened when the seeds were laid open in air for 10-14 d. Percentage germination decreased with the length of storing in refrigerator ((4±1) ℃), but it was not markedly affected for one month’s storage, with a decrease by 8.3% in comparison with the fresh seeds, and it was greatly affected by storing for more than three months, with values decreasing by 37%, 63%, and 81% for three months’, six months’ and 12 months’storage respectively. Difference in percentage germination as well as in LD was not significant for most lots after different storing periods between big seeds and small seeds, between fruit storage and seed storage, and between seeds in pulpy fruits or fleshy seeds and dry seeds.
陈章和 彭姣凤 张德明 赵建刚
摘要： 研究了南亚热带森林 90种木本植物的种子和果实的大小、含水量等特征及种子萌发 ,并对其中有足够萌发个体的种 (45种 )进行了萌发分析和对有足够萌发个体和足够种子的种 (41种 )进行了种子或果实储存对萌发影响的研究。肉质果实种子和肉质种子萌发率较干燥种子高 ,两者差异显著。大多数种播种 6 0d内萌发。肉质果实的种子和肉质种子较干燥种子的休眠期长 ,留土萌发种子较出土萌发种子休眠期长。大种子种与小种子种之间、夏季成熟的肉质果实的种子与冬季和春季成熟的肉质果实的种子之间休眠期长短差异不显著。萌发率与新鲜种子含水量无显著的相关 ,但种子中水分含量的减少明显影响萌发率 ,尤其是在种子自然干燥的最初 3d。当种子的水分含量减至 2 0 % (约在种子自然干燥 10～ 14d)时 ,种子萌发率降至很低。萌发率随储存时间 (密封 ,(4± 1)℃ )而下降 ,但储存一个月下降不大 (- 8.3% ) ,储存 3个月后 ,显著下降。果实储存与种子储存之间、大种子种与小种子种储存之间、肉质果实的种子和肉质种子储存与干燥种子储存之间 ,萌发率差异一般不显著。
Whole growing season pot experiments were conducted to examine the response of growth and water use efficiency (WUE) of spring wheat (Triticumaestivum L. cv. Gaoyuan 602) to CO2 enrichment. Wheat plants were grown in opentop chambers (OTCs) subject to two concentrations of CO2 (［CO2］)(350 and 700 μL/L, hereafter “ambient” and “elevated” respectively) and three soil water levels (80%, 60% and 40% field water capacity (FWC), hereafter “high soil moisture”, “medium soil moisture” and “low soil moisture”respectively). Elevated CO2 greatly increased leaf net photosynthesis (Pn) at all three soil water levels. The Pn of plants growing under elevated ［CO2］ was 22% lower than that of plants growing at ambient ［CO2］ when measured with the same ［CO2］ (700 μL/L). Plant growth was enhanced by elevated ［CO2］ throughout the growing season, with an increase of 14.8% in shoot dry weight at harvest under high soil moisture, and leaf area was increased by about 20% at all three soil water levels. Elevated ［CO2］ in combination with high soil moisture increased the ratio of plant shoot dry weight to height by 15.7%, while this ratio was decreased by over 50% when plants were subject to drought. Elevated ［CO2］ also increased the water use efficiency of wheat, mainly due to decreases in transpiration and cumulative consumption of water, and an increase in shoot dry weight, with the biggest value of 30% occurring at high soilwater moisture level. Compared to high soil moisture, drought decreased shoot dry weight by 72% under ambient ［CO2］, and by 76% under elevated ［CO2］. Similarly, drought also reduced WUE by 19% under ambient ［CO2］, and 23% under elevated ［CO2］. Our results indicate that: (1) elevated ［CO2］ can increase the photosynthetic rates, growth and WUE of wheat plants; (2) long term exposure to high ［CO2］ may result in lower photosynthetic capacity; (3) high ［CO2］ stimulates plants lateral growth more than vertical growth; (4) the effects of CO2 enrichment on plants depend on soil water status, with plants benefiting more from CO2 enrichment if sufficient water is supplied; and (5) drought may cause relatively more reduction in plant growth and WUE under future elevated ［CO2］ conditions.
吴冬秀1,2 王根轩3 白永飞1 廖建雄3 任红旭1
2. 河南大学生物系，开封475001；3. 兰州大学干旱农业生态国家重点实验室，兰州730000）
摘要： 利用开顶式气室对春小麦进行了一个生长季的CO2倍增盆栽实验,土壤水分控制为3个水平(分别为田间持水量(FWC)的80%、60%、40%).结果显示,CO2倍增显著提高小麦的光合速率.但在相同的CO2测定浓度下, 生长在加倍CO2浓度下的小麦的光合速率比当前CO2浓度下小麦低22%.高CO2浓度显著促进小麦生长,相对增加幅度在适宜水分下最大,为14.8%.80%FWC水分条件下高CO2使植株的干重/高度比增加15.7%.高CO2条件下,小麦的蒸腾速率降低、累积耗水量减少、水分利用效率(WUE)提高,WUE的提高幅度在适宜水分下最大,为30%.干旱(40%FWC)使小麦地上干重和WUE在当前CO2条件下分别降低72%和19%,加倍CO2条件下降低幅度较大,分别为76%和23%.根据以上结果得出结论: (1) 高CO2条件下, 小麦的光合速率、地上生物量和水分利用效率提高;(2) 植物长期生长于高CO2浓度导致光合能力降低;(3) 高CO2对植物侧向生长的促进作用大于垂直生长,即高CO2下植株将相对粗壮;(4) 高CO2对植物的生态效应依赖于土壤水分,在适宜水分下相对较大;(5) 在未来高CO2条件下,干旱引起的减产和水分利用效率减低幅度将会更大.
Water is usually considered to be a key limiting factor for the growth and reproduction of steppe plants in the Xilin River Basin, Nei Mongol. Foliar δ13C values, an indicator of long term intercellular carbon dioxide concentration and thus of water use efficiency (WUE) in plants, were measured on Leymus chinensis (Trin.) Tzvel. and Cleistogenes squarrosa (Trin.) Keng.in six communities of different habitats in the Xilin River Basin. The foliar δ13C values of both species tended to increase with decreasing soil water content (SWC) and a significant negative correlation was found between foliar δ13C values and SWC in different soil layers, indicating that the two species could change WUE according to water availability. We also found relatively constant leaf water contents (LWC) of the two species in different habitats. Our results implied that the two steppe species might have adapted to different soil water regimes either through adjusting stomatal conductance to get a proper WUE, or through enhancing the osmosis regulating ability to keep a relatively stable LWC. Our findings could partially explain why the two plant species have a wide distribution range and become dominant in the Xilin River Basin.
陈世苹 白永飞 韩兴国*
摘要： 用稳定性同位素技术,研究了锡林河流域不同群落和生境下羊草(Leymus chinensis ( Trin.) Tzvel.)和糙隐子草(Cleistogenes squarrosa (Trin.) Keng.)叶片δ13C值及其水分利用效率的变化.结果表明,在不同生境下,羊草和糙隐子草叶片δ13C 值随土壤水分含量的降低而增大,并与不同土层土壤水分含量均表现出极显著的线性负相关关系;而二者的叶片水分含量与土壤水分含量无显著的相关关系.这一结果说明,羊草和糙隐子草的水分利用效率均随土壤水分含量的降低而提高,而叶片水分含量保持相对稳定.这两种植物可能通过调节气孔导度、提高水分利用效率和增强渗透调节能力等生理生态机制适应水分状况不同的生境,从而使它们能够在锡林河流域不同植物群落中广泛分布并成为建群种或优势种.
关键词： 锡林河流域；羊草；糙隐子草；水分利用效率：δ13C 值
通讯作者。E-mail: xghan @ ns.ibcas.ac.cn
Two new stilbene glycosides (1 and 2), together with nine known compounds (3-11), were isolated from the water extract of Polygonum multiflorum Thunb. The structures of the new compounds were elucidated by their chemical properties and spectroscopic analyses, including extensive 2D NMR experiments. Compound 2 showed strong DNA cleavage activity, and compounds 1, 2 and 10 (2, 3, 4′, 5-tetrahydroxy-trans –stilbene-2-O-β-D-glucopyranoside) exhibited significant inhibition of lipid peroxidation.
肖 凯 宣利江 徐亚明* 白东鲁
摘要： 用反相层析法从何首乌(Polygonum multiflorum Thunb.)根茎的水提物中分得2个新的二苯乙烯甙(1、 2)及9个已知化合物:没食子酸(3)、 2,6-二羟基-苯甲酸(4)、吲哚-3-(L-α-氨基-α-羟基-丙酸)甲酯(5)、 1, 2-二羟基丙烷-1-(4-羟基-苯基) (6)、大黄素(7)、大黄素-8-O-β-D-葡萄糖甙(8)、(+)-lyoniresinol-3α-O-β-D-葡萄糖甙(9)、 2, 3, 4′, 5-四羟基反式二苯乙烯-2-O-β-D-吡喃葡萄糖甙(10)和 2, 3, 4′, 5-四羟基反式二苯乙烯-2, 3-二-O-β-D-吡喃葡萄糖甙(11).新化合物结构通过理化性质与波谱分析特别是 2D NMR得以确定.化合物2表现出很强的DNA裂解活性,化合物1、2与10具有很强的抗脂质过氧化活性.
用量子化学B3LYP/6-31G(d)方法，对Rhodopseudomena viridis细菌光合反应中心质体醌QA(MQ1)与泛醌QB(UQ1)间的电子转移耦合质子转移(PT-ET)机理进行了研究。 对反应(1)之后的Gibbs自由能变化进行了计算。 结果表明,(1) 按照各反应的数值， 在无耦合质子转移的情况下，UQ1不可能由MQ-1连续接受两个电子。由于ΔG0 2b0, ΔG0 3b0和G0 4b0，相应的PTET反应将依序沿(2b)、(3b)及(4b)进行。(2) 在气相情况下， 由于周围的氨基酸残基或水分子转移到UQ1的第一个及第二个质子(H+(1)和H+(2))将先后分别与UQ1的No.7和No.8氧原子结合；在蛋白环境情况下（SCRF方法，ε=4.0），质子耦合的顺序正相反， 但H+(1)和H+(2)与UQ-1结合的能量传递差很小。在气相及SCRF模拟环境中， 相同反应间的ΔG０无显著差别。（3）MQ-1间UQ-1的PTET反应如下： MQ1-+UQ1→MQ1+UQ1- (1) UQ1-(O(7)+H+(HisL190) →UQ1H (2b)(Gas) or UQ1－(O(8))+H+(H2O)→UQ1H (2b') (SCRF) or UQ1－(O(8))+H+ (ArgL217)→UQ1H (2b')(SCRF) MQ－+UQ1H→MQ1+UQ1H- (3b)(Gas) MQ1－+UQ1H→Q1+UQ1H- (3b') (SCRF) UQ1H-+H+(H2O)→UQ1H2 (4b)(Gas) or UQ1H－+H+ (ArgL217)→UQ1H2 (4b) (Gas) or UQ1H－+H+ (HisL190)→UQ1H2 (4b') (SCRF)
摘要: 2002年植物学科共受理面上申请项目449项,其中自由申请项目352项、青年项目42项和地区项目55项.另外,还受理了国家杰出青年科学基金17项、海外(香港)青年合作基金7项、重点项目9项、国家科学技术学术著作出版基金2项、国家自然科学基金研究成果专著出版基金6项.经评议,2002年本学科资助自由申请项目 69项、青年基金项目6项、地区基金8项、小额探索项目15项、国家杰出青年基金5项、海外青年学者合作研究基金2项和重点项目3项.本文还对各分支学科面上项目申请者的情况,以及学科建议资助项目遴选原则等进行了较为系统的分析.最后,还提供了2002年度植物学科资助项目情况一览表.
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