禺毛茛复合体及其近缘种过氧化物酶同工酶研究

对国产禺毛莨（Ｒａｎｕｎｃｕｌｕｓｃａｎｔｏｎｉｅｎｓｉｓ,ＤＣ）复合体及其近缘种８个种的１５个居群５２个个体的根进行了过氧化物同工酶研究,结果表明：（１）居群内过氧化物酶谱略有变异,同工酶酶谱或多或少能显示居群特征,供试的８个种中没有任何２个种的图谱完全一致,这说明在处级水平酶谱呈现出高度的分化现象。（２）根据染色体,孢粉和过氧化酶同工酶的资料推测,除Ｒ．ｓｉｌｅｒｉｆｏｌｉｕｓ（２ｘ）外,Ｒ．     

普通大麦和球茎大麦抗病种间杂种的产生及其同工酶标记

以二棱大麦（Ｈｏｒｄｅｕｍ ｖｕｌｇａｒｅ Ｌ．）“苏啤１ 号”为母本与四倍体球茎大麦（Ｈ． ｂｕｌｂｏｓｕｍＬ．）“ＧＢＣ１４１”杂交, 并通过幼胚培养获得１１ 株三倍体Ｆ１ 植株． 三倍体Ｆ１ 植株与二倍体母本二棱大麦“苏啤１ 号”回交, 获得７ 株二倍体回交后代ＢＣ１． ７ 个回交后代株系通过大麦黄花叶病病圃鉴定, 其中ＢＣ１－２株系抗大麦黄花叶病． 利用聚丙烯酰胺凝胶电泳对父本、母本和ＢＣ１－２株系进行了同工酶分析,结果表明二倍体二棱大麦与四倍体球茎大麦的过氧化物酶同工酶差异显著,并且在ＢＣ１－２株系幼根的过氧化物酶同工酶谱中,发现一条来自父本球茎大麦“ＧＢＣ１４１”的过氧化物酶谱带,该酶带的相对迁移率（Ｒｆ）为０．４７, 重复性好并且易于检测．由于回交后代ＢＣ１－２抗大麦黄花叶病, 又带有来自球茎大麦特异的幼根过氧化物酶谱带作为易于检测的同工酶标记,因此该回交后代株系可以作为大麦抗病育种工作重要的抗源．     

小麦与高冰草属间体细胞杂交获可育杂种植株

普通小麦（ＴｒｉｔｉｃｕｍａｅｓｔｉｖｕｍＬ．２ｎ＝４２）“济南１７７”与紫外线照射的高冰草（长穗偃麦草Ａｇｒｏｐｙｒｏｎｅｌｏｎｇａｔｕｍ,２ｎ＝７０）原生质体在ＰＥＧ诱导下融合,获杂种再生植株。取杂种子房诱导产生愈伤组织并再生植株,经染色体和同工酶鉴定,它们仍保留杂种性质。其中两株移栽成活并结实,杂种性质也经表型、染色体、同工酶和ＲＡＰＤ分析得到证明。在Ｆ０和Ｆ１代植株根尖细胞中,均发现高频率地存在着染色体断片;从Ｆ２代花粉母细胞减数分裂的染色体数目及行为发现,杂种细胞染色体数目主要分布在１８Ⅱ～２２Ⅱ,染色体断片发生配对及分离,表明它们是小染色体（ｍｉｎｉｃｈｒｏｍｏｓｏｍｅｓ）。Ｆ１及Ｆ２代植株比亲本小麦（“济南１７７”）秆茎粗硬、生长健壮,穗大粒大,已经产生具有优良性状的Ｆ２代穗系     

大血藤科植物的分类学研究

作者对大血藤科植物的花性、叶片内部结构形态、花粉形态、染色体核型及过氧化物酶和脂酶同工酶进行了比较研究,结果表明：１）大血藤科植物外形上的两性花,其雄蕊的形态退化、花药始终不开裂,为功能上的雌花,因此其花为单性,同株,同序或异序;１２）首次指出大血藤属植物的染色体数为２ｎ＝２ｘ＝２２,属小型染色体,与木通科植物２ｎ＝２ｘ＝３２、３０、２８的染色体数明显不同,支持Ｓｔａｐｆ（１９２６）将其从木通科分出另立为科的观点;３）单叶和复叶可出现于同一植株上,而且在叶片内部结构、花粉形态、染色体核型、过氧化物酶及脂酶同工酶等性状上,大血藤与单叶血滕间均无实质性的差异,因此将单叶血藤归并于大血藤中。     

禺毛茛复合体及其近缘种过氧化物酶同工酶研究

对国产禺毛茛（RanunculuscantoniensisDC．）复合体及其近缘种8个种的15个居群52个个体的根进行了过氧化物酶同工酶研究,结果表明：①居群内过氧化物酶谱略有变异。同工酶酶谱或多或少能显示居群特征。供试的8个种中没有任何2个种的酶谱完全一致,这说明在种级水平酶谱呈现出高度的分化现象。②根据染色体、孢粉和过氧化酶同工酶的资料推测,除R．silerifolius（2x）外,R．cantoniensis（4x）还有1个亲本。该亲本应具有“短m-型”染色体组,散沟和波状覆盖层的花粉,在其根的过氧化物酶酶谱中至少含A1、A2、C4和C64条酶带。③来自形态、染色体孢粉及同工酶的证据均证实R．vaginatus（5x）可能起源于（R,diffusus（4x）×R．sieboldii（6x）的杂交后代。     

大麦与纤毛鹅观草属间杂种F5和BC1F4的同工酶研究

对栽培大麦（ＨｏｒｄｅｕｍｖｕｌｇａｒｅＬ．品种“Ａｒｕｐｏ”）与纤毛鹅观草（Ｒｏｅｇｎｅｒｉａｃｉｌｉａｒｉｓ（Ｔｒｉｎ．）Ｎｅｖｓｋｉ）属间杂种后代Ｆ５和回交后代ＢＣ１Ｆ４（以“Ａｒｕｐｏ”作回交亲本）的不同类型株系与其双亲的幼根、幼芽、幼穗、幼嫩籽粒分别进行了酯酶、过氧化物酶同工酶分析。结果Ｆ５和ＢＣ１Ｆ４各株系的酯酶同工酶、过氧化物酶同工酶酶谱具有母本“Ａｒｕｐｏ”全部或绝大多数酶带,父本Ｒ．ｃｉｌｉａｒｉｓ的１～３条酶带和数量不等的双亲所没有的新酶带,也出现酶带的减少。结果表明,纤毛鹅观草的遗传物质已稳定地遗传给了其自交和回交后代。酶谱变异与植株习性出现一定程度的关联。由于在不同时期内结构基因的表达起不同作用,因此,在用同工酶分析法鉴定易位系时,最好不同的器官采用不同的酶类或一种同工酶多时期连续分析。     

宽叶韭种内分化的同工酶及可溶性蛋白的研究

采用聚丙烯酰胺凝胶电泳（ＰＡＧＥ）对宽叶韭的３个代表居群内不同植株间的过氧化物酶、酯酶和１６个居群间的酯酶（ＥＳＴ）、过氧化物酶（ＰＯＸ）、葡萄糖－６－磷酸脱氢酶（Ｇ６ＰＤＨ）、苹果酸酶（ＭＥ）、苹果酸脱氢酶（ＭＤＨ）、天冬氨酸转移酶（ＡＡＴ）、腺苷三磷酸酶（ＡＴＰａｓｅ）、乳酸脱氢酶（ＬＤＨ）８种同工酶系统以及可溶性蛋白进行了分析。结果发现：居群内不同植株的酶谱无差异;居群间的酶谱存在多态性,酶谱差异明显,且各居群均有其特征酶谱。采用“排序”方法和聚类分析,对宽叶韭１６个居群酶谱的相似系数和酶谱距离进行了研究。同工酶谱表型差异彼此显著的３个代表居群的可溶性蛋白双向电泳图谱也表现出明显差异,印证了同工酶的分析结果。结合细胞学的最新核型证据,从生物化学角度确定了这１６个居群间的亲缘关系和彼此的分化程度。结果表明：宽叶韭明显分为两大类,即冬季不倒苗和冬季倒苗两类,在同一类型中各居群之间彼此近缘,且冬季不倒苗的类型分化程度较高。本研究首次将多种同工酶的综合分析与聚类分析及可溶性蛋白双向电泳用于葱属植物的种内分化研究,为植物分子进化和系统学研究提供了科学依据     

芒果生长发育过程中若干生理参数的变化

研究结果表明：芒果植（苗）株过氧化物酶同工酶基本酶谱共不１０条,酶带面度２．６７ｃｍ,同一器官生育期不同,酶谱、Ｒｆ值、酶活性和酶带分布均有明显差异;果实不同成熟阶段,呼吸跃变与乙烯产生相关密切。     

棉属海岛棉×拟似棉F_1不育性研究

本文研究了棉属海岛棉［ＧｏｓｓｙｐｉｕｍｂａｒｂａｄｅｎｓｅＬ．,（ＡＤ）２］ｘ拟似棉［Ｇ．ｇｏｓｓｙｐｉｏｉｄｅｓ（Ｕ１ｂｒ）Ｓｔａｎｄｌｅｙ,Ｄ６］Ｆ_１植株的减数分裂及不育花粉的形成过程。Ｆ_１花粉母细胞在减数分裂中期Ｉ平均染色体构型为２４．８６Ⅰ＋６．９８Ⅱ＋０．０５Ⅲ。Ｆ_１不育的根本原因在于减数分裂中期染色体不能正常配对,引起部分染色体滞后及染色体不均等分配,从而产生多分孢子和微核,最终导致不育花粉的产生,并讨论Ｄ６与（ＡＤ）２间的亲缘关系以及克服Ｆ_１不育的方法。     

普通小麦—提莫菲维小麦白粉病抗性渐渗系中渗入片段的准确鉴定

用小麦（ Ｔｒｉｔｉｃｕｍ ａｅｓｔｉｖｕｍ Ｌ．） 第二部分同源群的３６ 个探针,对携带抗白粉病（ Ｅｒｙｓｉｐｈｅ ｇｒａｍｉｎｉｓｆ．ｓｐ ｔｒｉｔｉｃｉ） 基因Ｐｍ６ 的普通小麦提莫菲维小麦（ Ｔ．ｔｉｍｏｐｈｅｅｖｉ Ｚｈｕｋ ．） 渐渗系进行检测,通过这些渐渗系与受体亲本“Ｐｒｉｎｓ”之间杂交谱带多态性的比较,发现所测出多态性标记位点均位于这５ 个渐渗系的２Ｂ 染色体上,但其渗入片段的位置与大小有明显区别。ＩＧＶ１＿４５６ 和ＩＧＶ１＿４５８ 被鉴定为２Ｂ 染色体从短臂标记Ｘｃｄｏ４０５ 到长臂标记Ｘｂｃｄ１３５ 之间的区域已被提莫菲维２Ｇ 染色体区段所代替;而ＩＧＶ１＿４６３ 则在２Ｂ 染色体长臂Ｘｂｃｄ３０７ 到Ｘｃｄｏ６７８ 标记之间的区域被提莫菲维渗入成分所代替;ＩＧＶ１＿４６４ 、ＩＧＶ１＿４６５ ２ＢＬ染色体上的渗入片段更小,即ＩＧＶ１＿４６４ 在２ＢＬ染色体上标记Ｘｐｓｒ９３４ 与Ｘｂｃｄ１３５ 之间的区域有提莫菲维２Ｇ 染色质成分渗入,ＩＧＶ１＿４６５ 仅在Ｘｂｃｄ１３５ 附近有更小的外源成分渗入。根据５个渐渗系渗入成分重叠区段比较可把Ｐｍ６ 定位于２ＢＬ染色体上Ｘｂｃｄ１３５ ２ＢＬ标记的邻近区域内     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various