Embryogenesis represents the critical transition from the fertilized egg to the new multicellular seedling. Considerable attention has recently been focused on the search for genes expressed during the embryogenesis of plant model systems, especially in Arabidopsis thaliana (L.) Heynh., to understand the regulation of plant development. This paper presents a brief description of gene expression and molecular regulation during embryogenesis. The molecular events to induce and determine cell fate and cell differentiation are reviewed, the gene regulation of shoot and root meristems are discussed and the molecular mechanisms of embryo maturation and dormancy would be followed as well.
刁丰秋1 黄美娟2 吴乃虎1*
(1. 中国科学院发育生物学研究所，北京100080；2. 北京大学生命科学学院，北京100871）
In an earlier report the ultrastructure and nucleoid organelles of male gamete in Pinus tabulaeformis Carr. have been described. Presently, the ultrastructure of the cytoplasm of the egg cell and pollen tube—immediately before fertilization and during cytoplasmic transmission of male gametophyte—has been described for the same species. The fate of parental plastids and mitochondria in the proembryo has also been followed. The mature egg cell contains a large amount of mitochondria, but seems to lack normal plastids. Most plastids have transformed into large inclusions. Apart from the large inclusions, there are abundant small inclusions and other organelles in the egg cell. During fertilization, pollen tube penetrates into the egg cell at the micropylar end and thereafter the contents are released. Plastid and mitochondrion of male origin are lacking near the fusing sperm-egg nuclei. The second sperm nucleus—not involved in karyogamy—remains at a site near the receptive vacuole. This nucleus is surrounded by large amount of male cytoplasm containing mixed organelles from the sperm cell, tube cell, and egg cell. At the free nuclear proembryo stage, organelles of male and female origin are visible in the perinucleus-cytoplasmic zone. Most of the mitochondria have the same morphological features as those in the egg cell. Some of the mitochondria appear to have originated from the sperm and tube cells. Plastids are most likely of male gametophyte origin because they have similar appearance as those of the sperm and tube cell. Large inclusions in the egg cell become vacuole-like. Paternal plastids have been incorporated into the neocytoplasm of the proembryo. In the cellular proembryo, maternal mitochondria are more abundant. Plastids resembling those of the sperm and tube cell are still present. These cytological results clearly show that in P. tabulaeformis , plastids are inherited paternally and mitochondria bipaternally. The cytological mechanism of plastid and mitochondrion inheritance in gymnosperm is discussed.
国凤利1 胡适宜2*徐是雄3 袁宗飞2
2. 北京大学生命科学学院，北京100871；3. 香港大学植物学系，香港薄扶林道）
摘要：在电镜下观察油松（Pinus tabulaeformis Carr.）传粉后的胚珠临近受精时的花粉管和卵细胞的细胞质、受精时雄配子体细胞质的传递、游离核和细胞原胚发育时期质体和线粒体的传递。在成熟卵细胞中含许多线粒体，缺少正常结构的质体，它们转变为大内含体。此外，卵细胞还有丰富的小内含体和其他一些细胞器。花粉管在卵细胞的珠孔端释放其内含物。精核与卵核融合时，核周围未见来自精细胞的质体和线粒体。不参与融合的精核停留在接受液泡旁，在其周围有大量的雄性细胞质，其中混合有精细胞、管细胞和卵细胞的细胞器。在游离核原胚时期，核周区的细胞质中可见雄性与雌性亲本的细胞器相混合；其中许多线粒体与原来卵细胞中的线粒体有相同的形态，也有一些线粒体看来是来自精细胞和管细胞；质体是由雄配子体传递，形态与精细胞的或花粉管中的质体相似。卵细胞中变异的质体（即大内含体）在原胚发育时期变为液泡状，而雄性质体参加到新细胞质中。在原胚细胞中，线粒体大多数为母本来源，质体则表现为精细胞或管细胞的质体形态。该研究确定了油松具父系质体和双亲线粒体遗传的细胞学基础。对裸子植物线粒体和质体遗传的机理从细胞学的角度进行了分析。
Thin section technique was applied in the study of the initiation and development of the ovulate strobilus in Pinus tabulaeformis Carr. In the early August, as the primordium of ovulate strobilus occurred, cytohistological zonation of cone apex was similar to those of the vegetative shoot apex, but the cone apex appeared different from the vegetative shoot apex morphologically. In mid-October, the first bract primordium was formed in the axil scale at the cone base, then bract initiation had occurred in an acropetal direction. At this phase, cytohistological zonation of the cone apex has changed into two zones, the outer mantle of small cells was derived from the apical initial zone, central mother cell zone and peripheral zone, the inner pith of larger cells originated from the activity of the rib meristem. In the middle of March, ovuliferous scale primordia were acropetally formed in the axils of the developing bracts. In the middle of April, the bract attained approximately their full size, and a pair of anatropous ovules with single integument was initiated on the adaxial surface at the base of the fertile ovuliferous scale. Ovulate strobilus continued to grow during the fall and winter, while the vegetative shoot apex entered a dormancy. No basic structural difference was observed in the vegetative and reproductive apices, but apparent difference was present in the growth characteristics.
吴鸿1 崔大方1 胡正海2
（1. 华南农业大学生物技术学院，广州510642；2. 西北大学生物系，西安710069）
摘要：运用薄切片技术对油松 (Pinustabulaeformis Carr.)雌球果的发生和发育进行了研究。结果表明 :8月初 ,雌球果原基发生 ,其外部形态发生明显变化 ,但内部细胞组织学分区结构与营养茎端结构相似 ;10月中旬 ,雌球果原基的鳞片叶腋处产生最初的苞片原基 ,以后苞片原基由基部向顶端连续发生。此时球果原基的顶端结构发生变化 ,顶端分生组织区、中央母细胞区和周围分生组织区衍化为套层 ,肋状分生组织衍化为髓区 ;翌年 3月中旬 ,在苞片原基的叶腋处 ,珠鳞原基发生 ,其发生方向同样呈向顶发育 ;4月中旬 ,苞片体积已达到最终大小 ,此时 ,在珠鳞基部的近轴面分化出 2个具单珠被的倒生胚珠。油松雌球果原基在秋冬季依然保持生长 ,其营养茎端则进入休眠状态。尽管营养茎端和生殖端两类原基在结构上并无本质的区别 ,但在生长特性方面具有显著的差异。
Electron microscopic observations revealed that the tissues of poplar (Populus deltoides Bartr. ex Marsh) apical bud cells, which were fixed by a modified procedure of potassium permanganate fixative, showed a distinct endomembrane organization, in particular, the structural associations of the endoplasmic reticulum (ER) with other membrane systems. The striking findings are that some ER elements were in connection with the nuclear envelopes of two adjacent cells through plasmodesmata, and many ER elements were also associated with mitochondria, plastids, Golgi bodies or the plasma membrane (PM), forming a bridge-like continuum among various endomembrane systems or between nucleus to nucleus. A great number of plasmodesmata existed between cells, indicating a perfectly integrated symplasmic structure in poplar apical bud meristem grown in a long day environment. During the short day-induced dormancy, ER contracted, leading to its disassociation between nuclei, and between the nucleus and organelles/plasmalemma in many cells. After dormancy broke and shoots growth resumed, contracted ER was no longer observed in the apical bud cells. The ER associations with other endomembrane systems and the intercellular communication channels were re-established similar to that of plants before dormancy induction. These observations suggest that ER may play an important role in linking-up between the nucleus and organelles, and between the nucleus and the nucleus (or cell-to-cell), and seemingly coordinating various physiological processes by the bridging-like associations. And the contraction of ER under short-day may result in the growth cessation and the development of dormancy in poplar.
简令成1 孙龙华1 李积宏2 王红1 孙德兰1 Paul H LI 2
（1. 中国科学院植物研究所，北京100093；2. Laboratory of Plant Hardiness, Department of Horticultural Science and Plant Biological Sciences Program, Universoty of Minnesota,St. Paul,MN 55108,USA)
摘要：电镜细胞化学观察揭示 ,不抗寒的玉米 (Zeamays L .cv.BlackMexicanSweet)和抗寒的小偃麦 (Triticum sect.Trititrigia mackey)细胞在 2 6℃悬浮培养时 ,标志Ca2 + 定位的锑酸钙沉淀物主要分布在液泡内 ,细胞质和细胞核中很少见到Ca2 + 沉淀 ;标志Ca2 + _ATPase活性反应的磷酸铈沉淀物丰富地分布在质膜上 ,显示这两种植物质膜Ca2 + _ATPase在 2 6℃培养中有着较高的活性。当这二者的细胞在 4℃低温培养 1h和 3h后 ,二者细胞质和细胞核中的Ca2 + 浓度都明显地增加 ,但质膜Ca2 + _ATPase活性没有明显改变。在继续延长低温培养后 ,二者之间的Ca2 +水平和Ca2 + _ATPase活性发生明显的区别 :在不抗寒的玉米细胞中 ,质膜Ca2 + _ATPase活性显著降低 ,甚至完全失活 ,细胞内增加的Ca2 + 水平不降低 ,不能恢复Ca2 + 的稳定平衡 ,细胞的精细结构受破坏 ;抗寒的小偃麦细胞则相反 ,在 3h以后的低温培养过程中 (至 3d) ,质膜Ca2 + _ATPase仍然保持高活性 ,细胞内增加的Ca2 + 浓度迅速降低 ,恢复Ca2 + 的稳定平衡 ,并提高抗寒力。这些结果表明 ,植物在低温条件下 ,质膜Ca2 +-ATPase活性的维持亦即细胞内Ca2 + 稳定平衡的恢复与其抗寒性有着密切的关系 ,对于它们在逆境中生存起着重要作用。
关键词： Ca2+ ；质膜Ca2+-ATPase；Ca2+ 的稳定平衡；植物抗寒性；玉米；小偃麦
The reorientation of microtubules (MTS) in roots of Oryza sativa L. treated with 2,4-D was studied using confocal laser scanning microscopy. In the control (the roots were not treated with 2,4-D), different distribution patterns of MTS were observed in the different growth zones of root tips. MTS of the cortical cells were randomly aligned in the zone of cell division. They were transversely arranged in the cortical cells of the zone of cell elongation; and obliquely oriented in the root hair zone. After treatment with 2,4-D, MTS displayed distinct changes with reorientation in the cortex of the root tip coupling with the inhibition of root growth. MTS changed their orientation in the cortical cells of the zone of cell division from being randomly oriented to transversely oriented when incubated in 1 mg/L 2,4-D for 1 h. However, they were recovered and became randomly oriented when the roots were treated with 1 mg/L 2,4-D for 24 h. An array of MTS, which was different from that in the control, was observed in the cortical cells of the zone of cell elongation in the roots treated with 1 mg/L 2,4-D for 1 h. After treatment with 10 mg/L 2,4-D for 1 h, the MTS in the cortical cells of the zone of cell division became transversely reorientated, but the pattern of MTS distribution was different from that in the 1-hour treatment of 1 mg/L 2,4-D. MTS were hardly detected in the same type of cells when roots were submerged in 10 mg/L 2,4-D for 24 h. When roots were incubated in 10 mg/L 2,4-D for 1 h, the MTS of the cortical cells in the zone of cell elongation became randomly oriented, and much more randomly when the roots were treated for 24 h.
摘要：摘要： 通过共焦激光扫描显微镜对经过2,4-D 处理水稻（Oryza sativa L. ）根尖的微管骨架的排列进行了研究。结果表明，对照（未经2,4-D 处理）根尖的不同生长区微管呈现不同的排列方式，生长区皮层细胞微管呈随机排列，伸长区微管呈横向排列，根毛区的呈斜向排列。经过2,4-D 处理的根，不但皮层细胞微管表现重新定向，同时也伴随着生长受到强烈抑制。1 mg/L 2,4-D处理1h，分生区细胞微管由随机排列变成横向排列；处理2,4-D 后，微管恢复成随机排列。伸长区皮层细胞在1mg/L. 2,4-D处理1h后，其细胞内出现完全不同于对照同一区域细胞排列方式的微管。10mg/L2,4-D 处理1h使分生区皮层细胞微管排列改变成横向，但不同于10mg/L2,4-D 处理的；处理24h后，分生区皮层细胞内的大部分区域未观察到微管。伸长区细胞在10mg/L 2,4-D 处理1h后，微管变成随机状，处理24h 后随机程度更加明显。
Hydrilla verticillata (L. f.) Royle was cultivated in water medium polluted with Hg2+and Cd2+ of different gradient concentrations for 3 days and 6 days respectively. Leaves of H. verticillata lost their green color gradually with the increasing pollutant concentration. Ultrastructural observation showed, at its early stage, dispersion of dictyosomes, disintegration after swelling of endoplasmic reticulum, swelling or vesiculation of thylakoids of chloroplasts and cristae of mitochondria and condensation of chromatin of nucleus. More serious damage was shown in the plant cells with heavier pollution, such as disappearance of ribosomes, agglutination of chromatin of nucleus, dispersion of nucleolus, disruption of nuclear membrane, disintegration of chloroplasts and mitochondria, collapse of plasmodesmata due to plasmolysis, focal dissociation of cell wall and eventually cells death. The results indicated that Hg2+ and Cd2+ might injure all the membranous and non-membranous structures of cells, though there existed different degrees of endurance of cell structures to the poison. The lethal concentration of Hg2+ to cell of H. verticillata ranged from 1 to 2 mg/L, and that of Cd2+ ranged from 2 to 3 mg/L.
施国新 杜开和 解凯彬 丁小余 常福辰 陈国祥
摘要：黑藻 (Hydrillaverticillata (L .f.)Royle)植株分别在Hg2 + 、Cd2 + 梯度浓度的污染水中培养 ,在培养的时间段中(Hg2 + 为 3d ,Cd2 + 为 6d) ,随着浓度的递增 ,叶片逐渐出现均匀褪绿症状。电镜观察发现 ,叶细胞遭受Hg2 + 、Cd2 + 毒害初期 ,高尔基体消失 ,内质网膨胀后解体 ,叶绿体中的类囊体和线粒体中的脊突膨胀或呈囊泡状 ,核中染色质凝集。随着叶细胞遭受毒害程度的加重 ,核糖体消失 ,染色质呈凝胶状态 ,核仁消失 ,核膜破裂 ,叶绿体和线粒体解体 ,质壁分离使胞间连丝拉断 ,细胞壁部分区域的壁物质松散游离 ,最后细胞死亡。结果表明 :Hg2 + 和Cd2 + 对细胞的膜结构和非膜结构都产生毒害作用 ,只是不同的结构对毒性的耐受性有一定的差异。Hg2 + 对黑藻的致死浓度为1～ 2mg/L ,Cd2 + 为 2～ 3mg/L。
关键词： 黑藻；Hg2 + ；Cd2 +污染；超微结构
A twinovary mutant derived from the doubled haploid (DH) progeny of a cross,02428/Gui 630, was presumably related to the transposition of some transposable elements. Up to date, all reported the active transposable elements in rice (Oryza sativaL.) are copia like retrotransposons. In the present study, the reverse transcriptase domains of copia like retrotransposons were amplified from the total DNA isolted from the mutant plants with the degenerated oligonucleotide primers for the domain. Three cloned insert DNAs, R331, R334 and R338, representing putative different copialike retrotransposons were screened out. Two of them displayed high polymorphism between “Zhaiyeqing 8” and “Jingxi 17”. Nine of the polymorphic bands were mapped on seven rice chromosomes. Sequencing analysis revealed that stop codons frequently occur in the sequence of R338, while both R331 and R334 contain a continuous coding region for 81 putative amino acid residues. No significant variation in hybridization patterns was found between indica and japonica rice or among 26 varieties of indica rice when R33 1 was used as a probe. Nevertheless, when R33 4 was used as a probe, high polymorphisms were detected both between indica and japonica rice and among 26 indica varieties, implying that this element might still be active in rice genomes.
王文明1 朱立煌1* 谢戎2 谢灿1 金良2
（1. 中国科学院植物生物技术开放实验室，北京100101；2. 四川省农业科学院水稻高粱研究所，四川泸州646000）
摘要：从水稻（Ｏｒｙｚａ ｓａｔｉｖａ Ｌ．）育种后代材料中获得一个受单隐性基因控制的颖花器官突变体，该突变体的内外释变，每个颖花含１～３个发育完整的雌蕊，其他雌蕊发育不完全。有的雌蕊化的雄蕊下部为花丝，其上着生不规则在组织和０～３个羽毛状柱头。横切面和纵切面观察均可见每个颖花含３个子房。人工辅助授粉后，每个颖花可产生１～２粒种子根据这些结果推断，该突变体为类似Ｂ功能缺失的突变体。
Under a given condition of crystallization, dark brown short rhombohedron crystals could be obtained from ΔnifZ MoFe protein purified from a nifZ deleted mutant strain of Azotobacter vinelandii Lipmann. Systematic studies on the effect of concentrations of PEG 8000,MgCl2, NaCl,Tris and buffer pH on the crystallization and crystal growth of the protein showed that the protein could not be crystallized in lower concentrations of the chemicals and lower buffer pH. A large amount of smaller crystals of the protein appeared in a week with gradual increasing in the chemical concentrations and pH≥8.0. When the chemical concentrations were further increased, the time for crystallization was increased and a few high grade crystals of larger size were formed. If the concentrations of the chemicals were continuously increased, many crystals with smaller size, and, sometimes of poor quality appeared again and eventually ceased to produce any crystals. The optimal concentration for each of the above mentioned chemicals varies with other variable factors. Only one bigger crystal (both of the longest two sides: 0.16 mm) could be obtained in a hanging drop of protein sample when the concentrations of PEG 8000, MgCl2, NaCl,Tris and protein were kept at 1.86%, 300 mmol/L, 400 mmol/L, 53 mmol/L and 4.64 g/L , respectively, with Tris buffer pH 8.2.
黄巨富1 王耀萍2 董志刚1 黄孝明1 汪道涌1 吕玉兵1 汪志平1
（1. 中国科学院植物研究所，北京100093；2. 中国科学院生物物理研究所，北京100101）
摘要：在一定的结晶条件下 ,缺失nifZ的棕色固氮菌 (Azotobactervinelandii Lipmann)突变种钼铁蛋白将从溶液中结晶出深棕色的短斜四棱柱晶体。PEG 80 0 0、MgCl2 、NaCl、Tris的浓度及缓冲液的pH对该蛋白的结晶及晶体生长影响的系统研究表明 ,浓度和pH较低时 ,不出晶体 ;随着浓度逐渐提高及pH高于 8.0 ,在一周内出现大量小晶体 ;再提高浓度 ,便延长结晶时间但出质好、体积大而数少的晶体 ;然后晶体随浓度的提高而又变小、变多、甚至晶质变差 ,直至不再出晶体。影响晶体生长的各因子的最适浓度随其他条件的改变而有所不同。当缓冲液的pH为 8.2而PEG 80 0 0、MgCl2 、NaCl、Tris和蛋白质的浓度分别为 1.86 %、30 0mmol/L、40 0mmol/L、5 3mmol/L和 4.6 4g/L ,在一滴悬滴液中只有一颗较大的优质晶体 (最大两边线均为 0 .16mm)。
关键词： 棕色固氮菌；缺失nifZ 的突变种；MoFe 蛋白；晶体生长
Changes in photosynthetic activities were studied with tobacco (Nicotiana tabacum L.) leaves and chloroplasts infected by cucumber mosaic virus (CMV) at the top, middle and bottom located leaves. Net photosynthetic rate was reduced at all three positioned leaves, with the maximum reduction occurring at the top leaves (31.9% of control). The infected chloroplasts showed a reduction in electron transport rates of the whole chain electron transport, photosystem Ⅱ (PSⅡ) and photosystem Ⅰ (PSⅠ). Since the decline in the whole chain electron transport (15.6% of control, H2O→MV) closely paralleled the decline in PSⅡ activity (20.9% of control, H2O→PBQ), the inhibition of the latter was probably responsible for the overall decrease. Chlorophyll a fluorescence measurements showed a variable reduced fluorescence yield (Fv/Fo) which indicated that PSⅡ was impaired and the CO2 assimilation was disturbed by CMV infection. Fluorescence emission spectra at 77 K indicated that energy distribution between PSⅡ and PSⅠ was affected. F686/F734 of infected leaves and chloroplasts increased and the greatest increase (331.1% of control ) was found in the top leaves. These data may conclude that the infection inhibited mainly the PSⅡ activity.
王春梅1,4 施定基1* 朱水芳2 田波3 魏宁生4
（1. 中国科学院植物研究所光合作用研究中心，北京100093；2. 农业部植物检疫研究所，北京100029；
3. 中国科学院微生物研究所，北京100080；2. 西北农业大学植保系，陕西杨陵712100）
摘要：研究了烟草 (Nicotianatabacum L .)感染黄瓜花叶病毒后烟草植株不同部位 (顶层、中层、下层 )叶片的光合速率和叶绿体光化学反应的变化。感病的叶片净光合速率减少 ,顶层叶减少最多。病毒侵染抑制PSⅡ活性比PSⅠ活性更明显 ,特别是顶层叶。叶绿素a荧光测定表明还原态Q库减少 ,CO2 同化减少。从低温荧光发射光谱图变化中发现能量分配受干扰。
Change of antioxidant capacity of the organic-free-radical scavengers to 1.1-diphenyl-2-picrylhydrazyl (DPPH·) reagent in the leaf extracts of the seedlings and young trees of four woody species (Schima superba Gardn. et Champ., Castanopsis fissa (Champ. ex Benth.) Rehd. et Wils., Psychotria rubra (Lour.) Poir., Ardisia quinquegona Bl.) in exposureto different light intensities was investigated. The organic free radical scavenging capacity (ORSC) expressed as the percentage of decreasing DPPH· was 16%-59% (pot seedlings) or 48%-88% (young trees in the forest). The highest ORSC was observed in plants grown under natural light, and the ORSC reduced with the decreasing light intensity. Similar trend was observed through the assay of inhibition to linoleic acid oxidation. The ORSC of P. rufra, an understory shrub, was more sensitive to the change of light intensity. A linear relationship was found between ORSC and AsA (ascorbic acid) content (r=0.92) or the absorption around the wavelength of 204-227 nm. It is proposed that ORSC of leaf was regulated by incident light intensity, and the contents of AsA and, flavonoid phenolics might be the important components contributed to ORSC and total antioxidant activity of leaves. The increasing ORSC is likely to be a protective strategy of plant in response to strong light.
彭长连 林植芳 林桂珠
摘要：生长在不同光强下的 4种木本植物荷树 (Schimasuperba Gardn .etChamp .)、黧蒴 (Castanopsisfissa (Champ .exBenth .)Rehd .etWils.) (乔木 )和九节 (Psychotriarubra (Lour.)Poir.)、罗伞 (ArdisiaquinquegonaBl.) (林下灌木 )幼苗(盆栽 )或幼树 (自然林下 )叶片的 5 0 %乙醇提取液具有明显的清除有机自由基二苯基苦基苯肼 (1,1-diphenyl-2-picrylhydrazyl,DPPH·)的能力。清除率在 16 %～ 5 9% (盆栽苗 )和 48%～ 88% (林下幼树 )之间 ,自然光下生长的植物对DPPH·有机自由基的清除能力 (organicfreeradicalscavengingcapacity ,ORSC)最强 ,降低光强减弱叶片的ORSC。林下灌木九节的ORSC对光强变化有较高的敏感性。几种植物的ORSC及其随光强的变化与叶片的抗坏血酸 (AsA)含量和叶提取液在 2 0 4～ 2 2 7nm紫外区的吸光值皆呈线性相关。结果认为 ,光调节叶片的ORSC ,AsA和黄酮类、酚类化合物是贡献于ORSC总抗氧化活性的重要组分 ,提高ORSC是植物响应于强光的保护策略。
Dunaliella salina (Dunal) Teod. and Platymonas helgolandica Kylin var. tsingtaoensis were cryopreserved in liquid nitrogen with a two-step cryopreservation method. With 5% and 20% dimethylsulphoxyde (DMSO) concentration respectively through 30 min equilibrium time, and under -40℃, 60 min and -30℃, 30 min respectively as prefreezing temperature and sustained time, and by using slow dilution method to remove DMSO from the sample at 0℃ and room temperature respectively after sample thawing, D. salina and P. helgolandica var. tsingtaoensis gained the highest survival rates that were 68.5% and 78.3% respectively.
王起华 张恩栋 李大鹏 程爱华
摘要：采用两步法冷冻技术超低温保存盐生杜氏藻 (Dunaliellasalina (Dunal)Teod .)和青岛大扁藻 (Platymonashel golandica Kylinvar.tsingtaoensis)。当二甲基亚砜 (DMSO)浓度分别为 5 %和 2 0 % ,平衡时间均为 30min ;预冻温度及保持时间分别为 - 40℃ ,6 0min和 - 30℃ ,30min ;化冻后分别在 0℃和室温下采用慢速稀释法去除DMSO时 ,盐生杜氏藻和青岛大扁藻都达到了最高存活率 ,分别为 6 8 5 %和 78 3%。
RAPD (random amplified polymorphic DNA) markers were generated from filaments of 15 Porphyra lines representing four important groups, P. yezoensis, P. haitanensis, P. katadai var. hemiphylla and P. oligospermatangia. Among the total 69 fragments generated by 6 selected primers (among 50 primers), 67 appeared to be polymorphic (97.1%). Cluster analysis based on the RAPD results was performed. The 15 Porphyra lines were divided into 3 groups. This result was consistent with that from taxonomy analysis. A DNA fingerprinting based on 8 bands amplified with OPN-02 and OPJ-18 was constructed and might be used in Porphyra variety identification. Five specific RAPD fragments of 5 Porphyra lines were isolated and cloned into pGEM-T easy vector. These five RAPD fragments may be useful in germplasm identification and property protection of Porphyra.
贾建航 王萍 金德敏 曲雪萍 王倩 李传友 翁曼丽 王斌*
摘要：用RAPD技术对 4类紫菜 (Porphyrayezoensis,P .haitanensis,P .katadaivar.hemiphylla和P .oligosper matangia)的 15个无性系丝状体进行了遗传多样性分析 ,从 5 0个OPERON引物中经过初筛 ,其中 6个引物可以扩增出稳定的可重复的图谱。这 6个引物共扩增出了 6 9条带 ,多态性比例达 97.1%。根据RAPD结果将这 15个无性系聚类为 3个群 ,此聚类结果与分类地位基本相符。利用来自引物OPJ_18和OPN_0 2扩增的 8条多态性条带构建了紫菜的DNA指纹图谱 ,该图谱可以方便地应用于紫菜无性系的种质鉴定。本研究还回收并克隆了 5个紫菜无性系的 5条特异片段 ,将用于无性系鉴定、种质资源保护和产权保护。
In order to perform mutational studies on genes from the self-incompatibility (S) locus, an S locus-directed transposon tagging system was established in Antirrhinum. Cultivated lines of Antirrhinum majus contain many molecularly well-characterized transposons, but are self compatible due to the presence of a nonfunctional S locus (Sc). In this study, an active transposon (Tam5) from the Cycloidea (Cyc) locus controlling flower asymmetry in A. majus was introduced to a position tightly linked to the functional S locus from self incompatible interspecific hybrids (A. majus×hispanicum) through genetic recombination. RFLP (restriction fragment length polymorphism) analysis showed that the transposon is 3 cM (centiMorgan) away from the S locus and retains high transpositional activity with a germinal excision frequency of 20%. Possible implications of the linkage between the S locus and genes controlling floral phenotypes were discussed. An active transposon tightly linked to the S locus constructed here will facilitate the generation of insertional mutants of the S locus encoded genes and may lead to dissecting their precise roles during self-incompatible reactions.
摘要：栽培金鱼草 (Antirrhinummajus L .)中有许多分子生物学上研究得较为透彻的DNA转座子 ,但是它们的S位点已经失去了功能 (Sc)位点 ,故而为自交亲和。为了利用这些转座子进行S位点选择性的转座子标定实验 ,将一个来自栽培金鱼草花型基因Cyc的活跃转座子Tam5通过遗传重组的方法引入到与自交不亲和金鱼草种间杂种(A .majus×hispanicum)S位点紧密连锁的位置。限制性酶切片段长度多态性 (RFLP)的分析证明该转座子距S位点约 3cM (centiMorgan) ,并且保持了较高的转位活性 ,其配子切除频率高达 2 0 %。同时 ,还讨论了花型和自交不亲和性基因连锁的可能的生物学意义。所建立的S位点选择性的转座子标定体系为详细研究金鱼草S核酸酶基因及其不同结构域在自交不亲和反应中的作用提供了新的技术平台。
关键词： 转座子标定；S 位点；金鱼草
Metallothionein (MT) has two domains, α and β domain. α domain preferred to bind Cd2+and Hg2+. Mouse metallothionein mutant αα has been constructed and expressed in E.coli, which has the same stability as the nature one but has stronger affinity to heavy metals. To testify the result in vivo, αα mutant gene was cloned into plant expression vector pE3 under the CaMV 35S promoter. A transgenic tobacco was obtained by using leaf discs of tobacco (Nicotiana tabacum L. cv. NC89) to Agrobacterium-mediated ααgene transfer. Southern blotting analysis indicated that the αα mutant gene was indeed integrated into the tobacco genome; Western blot indicated that the αα mutant gene was expressed in transgenic tobacco. It was also demonstrated that the transgenic tobacco with αα mutant gene have a little higher tolerance to heavy metals than that with natural MT gene. Moreover, the transgenic tobacco can accumulate more Cd2+ in its roots than natural, so that, it can decrease the concentration of Cd2+ in its leaves.
张晓钰 周慰 茹炳根*
摘要：金属硫蛋白（ＭＴ）有α、β两个结构域，其中α结构域优先结合Ｃｄ+２＋、Ｈｇ+２＋以α结构域代替β结构域而得到的αα突变体在大肠杆菌构建及表达后，体外实验证明其具有同天然ＭＴ相似的稳定性，但结合重金属的能力稍强于天然ＭＴ。将αα突变体转入植物表达载体，以ＣａＭＶ３５Ｓ为启动子，利用根癌土壤杆菌（Ａｇｒｏｂａｃｔｅｒｉｕｍ ｔｕｍｅｆａｃｉｅｎｓ（Ｓｍｉｔｈ ｅｔ Ｔｏｗｎｓｅｎｄ）Ｃｏｎｎ）介导的叶盘法转化烟草（Nicotiana tabacum L.cv. NC89 ）。Southern Western 证明了外源基因在烟草内的整合与表达。重金属抗性结果证明：转αα突变体烟草在300umol/L CdCl2的培养基中可正常生长，转天然MT的烟草在含200umoL/L)CdCl2的培养基中生长，而野生型烟草只能在含75umol/LCdCl2的培养基中生长。Cd2+ 含量及分布实验证明：转基因烟草同天然烟草相比，根部吸收了大部分Cd2+ ，从而降低了叶部Cd2+含量。
A new triterpenoid saponin containing five sugars was isolated from the ethanolic root extract of Dipsacus japonicus Miq., and its structure was established as 3-O-［β-D-glucopyranosyl(1→4)］［α-L-rhamnopyranosyl(1→3)］-β-D-glucopyranosyl(1→3)-α-L-rhamnopyranosyl(1→2)-α-L-arabinopyranosyl-oleanoic acid. The sites of glycosylation and the sequence of sugars in the glycoside can be determined unambiguously and total assignment of severely overlapping proton resonance of sugar residues were achieved by a combined use of the 1D-SEMDY and NOE difference spectroscopy in rotating frame techniques, without having recourse to chemical degration or modification. The results showed that these new NMR techniques are very effective and convenient for the structure determination and spectral assignment of this class of compounds.
缪振春1* 冯锐1 周永新1 魏锋2
（1. 军事医学科学院毒物药物研究所，国家生物医学分析中心，北京100850；2. 北京医科大学药学院，北京100083）
摘要：从日本续断 (Dipsacusjaponicus Miq .)根的乙醇提取物中分得一个新的三萜皂甙 ,其结构被鉴定为 3_O_[β_D_吡喃葡萄糖 (1→ 4) ][α_L_吡喃鼠李糖 (1→ 3) ]_β_D_吡喃葡萄糖 (1→ 3)_α_L_吡喃鼠李糖 (1→ 2 )_α_L_吡喃阿拉伯糖 齐墩果酸。采用一维SEMDY谱和旋转坐标NOE差谱核磁共振新技术相结合的方法 ,对糖体间和糖体与甙元间的连接顺序和连接位置进行了研究。该方法的测定结果可靠 ,使用方便 ,不需要对化合物进行化学降解和衍生化 ,糖基上重叠的1H_NMR信号可以分辨和明确归属。
A kind of silicified fossil wood with mixed pits on the radial tracheid wall is described. The fossil wood was collected from the top of Taiyuan Formation (early Early Permian) in Wuda Mining District, Nei Mongol. Compared with the Paleozoic fossil woods in the world, it is put into Araucarioxylon Kraus and named as A. laoshidanense sp. nov. Based on the character of possessing mixed pittings (alternate and opposite pittings) on the radial tracheid wall, the fossil wood is believed to be one of the unknown primitive conifers.Diagnosis of the new species: Only secondary xylem preserved and consisting of axial tracheids and rays. Growth ring boundary, resin duct and axial parenchyma absent. One to Four (commonly 2or3) seriates of bordered pits mostly alternate but sometimes opposite）on the radial tracheid wall. One to Four (commonly1, rarely2 to 4) Cupressoid pits in each cross-field. Rays usually uniseriate, sometimes partly-biseriate and 2 to 39 (mainly3-5) cells high.
王士俊 胡雨帆 崔金钟
摘要：报道了一种具混合型纹孔（互列式纹孔和对列式纹孔）的化石木。化石木产自内蒙古乌达矿 区老石旦矿附近太原组上部，地质时代为早二叠世早期。经比较，确认为南洋杉型木属(A raucarioxylon Kraus)一新种：老石旦南洋杉型木(Araucarioxylon laoshidanense sp. nov.)。根据混合型纹孔的存在及其他特征，认为新种可能代表了一种原始的松杉 类植物的木材化石。主要特征： 仅保存有次生木质部，无生长轮，仅由轴向管胞和木射线构成，未见轴向薄壁 组织和树脂道。管胞排列紧密，径向壁具缘纹孔1～4列，其中2～3列者较常见。纹孔的排 列以互列紧挤为主，也有少量对列-亚对列的纹孔。交叉场内多具1～2个柏木式纹孔。木射 线多为单列，少数为部分双列，高2～39个(多为3～5个)细胞。
关键词: 早二叠世； 太原组； 化石木； 南洋杉型木属； 老石旦南洋杉型木(新种)
利用瞬时表达系统研究马铃薯Y 类病毒基因对豌豆Hsp70 基因启动子激活能力的差异
摘要：建立了一个瞬时表达系统以研究豌豆种传花叶病毒（ＰＳｂＭＶ，一种马铃薯Ｙ类病毒）不同基因对豌豆（Ｐｉｓｕｍ ｓａｔｉｖｕｍ Ｌ．）Ｈｓｐ７０基因启动子激少能力的差划。构建了豌豆Ｈｓｐ７０基因启动子指导下的ＧＵＳ基因的表达载体，同时还制备了３５Ｓ启动子指导下的ＰＳｂＭＶ Ｐ１和Ｐ３基因的表达载体。以表达载体ＤＮＡ包被才金焰做子弹，利用基因枪对豌豆离体叶片进行共轰击实验，结果表明，ＰＳＢＭＶ Ｐ１和Ｐ３
Fossil Sequoia in Yunnan Province, China during the Miocene is here reported for the first time. The morphological features of shoots and cuticle are described. Its historical and geological distribution is also discussed. According to the characteristics of the assemblage of spore and pollen in the fossil collection site and the nature environment of the native S. sempervirens lived in American, the discovery of the fossil Sequoia indicated the presence of moist subtropical climate in Yunnan Province during the Miocene.
马清温1 徐景先2 王宇飞2 李承森2
（1. 聊城师范学院生物系，山东聊城252059；2. 中国科学院植物研究所，北京100093）
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