基于rbcL序列试论鸢尾属部分物种间的系统发育关系

选用叶绿体rbcL基因对鸢尾属植物的分类和系统发育进行了分析。以雄黄兰为外类群,对21份鸢尾属材料和GenBank下载的共49条序列采用最大简约法构建系统进化树,探讨了鸢尾属的分类系统。针对有争议的物种,聚类结果表明：马蔺与白花马蔺关系较远;扁竹兰和蝴蝶花亲缘关系较扇形鸢尾近;细锐果鸢尾和锐果鸢尾亲缘关系近,大锐果鸢尾较之远;四川鸢尾和薄叶鸢尾聚类近;西伯利亚鸢尾系内物种间聚类复杂,亲缘关系不清楚。     

A preliminary study on the distribution pattern of isoflavones in rhizomes of Iris from China and its systematic significance

A comparative isoflavonoid analysis of 22 species of Iris, representing almost all the subgenera, and one species of its allied genus Balamcanda, B. chinensis (L.) DC. was carried out by TLC, with iridin, tectoridin, irigenin, tectorigenin, irisfloretin, dichotomin, wogonin, rhamnazin, apocynin, androsin being used as authentic compounds. The results show that the isoflavones are the characteristic constituents of Iris and Belamcanda. According to the distribution pattern of isoflavones, the Iris species here studied can be divided into 2 groups; one contains isoflavonoid aglycons, while the other contains both glycosides and isoflavonoid aglycons. From the point view of chemosystematics, subgen. Limniris contains isoflavonoid aglycons only and might be a natural group; subgen. Crossiris might be also a natural group when Iris speculatrix Hance is excluded; subgen. Pardanthopsis is similar to B. chinensis in the chemical constituent might be a primitive group in Iris and has close relationship with subgen. Crossiris, subgen. Xyridion and subgen. Iris. Based on the evidence from phytochemistry, palynology and cytology, Iris cathayensis Migo and I. mandshurica Pall. are considered intermediate groups between subgen. Limniris and subgen. Iris and I. speculatrix Hance an intermediate group between subgen. Limniris and subgen.Crossiris, while I. confusa Sealy and I. wattii Baker might be conspecific.     

中国鸢尾属植物根茎中异黄酮类成分分布的初步研究及其系统学意义

本文对鸢尾属Iris 22个种(基本上包括了各个亚属的代表)及其近缘属植物射干属Belamcanda的 射干 B．chinensis(L．)DC．进行了根茎的异黄酮类成分的比较分析研究。结果表明,鸢尾属植物和射干 中普遍具有异黄酮类成分,这是它们的特征性成分之一。根据化学成分的特征,鸢尾属可以分为两大类 群：只含异黄酮甙元的类群和既含异黄酮甙又含甙元的类群。从化学成分的分布特征来看,无附属物亚 属subgen．Limniris只含异黄酮甙元,是一个比较自然的类群。鸡冠状附属物亚属subgen．Crossiris,除小 花鸢尾 I．speculatrix Hance外,是一个较自然的类群。野鸢尾亚属subgen．Pardanthopsis和射干属的成分 非常相似,有着密切的亲缘关系,是鸢尾属中原始的类群。从化学成分特征来看,野鸢尾亚属与琴瓣鸢 尾亚属subgen．Xyridion、鸡冠状附属物亚属、须毛状附属物亚属subgen．Iris都有着一定的联系。根据化 学成分、孢粉学、细胞学等特征,认为：华夏鸢尾I．cathayensis Migo和长白鸢尾I．mandshurica Maxim．为无附属物亚属与须毛状附属物亚属两亚属之间的过渡类型。小花鸢尾是无附属物亚属向鸡冠状附属物亚属过渡的中间类型。扁竹兰I．confusa Sealy和扇形鸢尾I．wattii Baker可能是同一个种。     

德国鸢尾对Cd胁迫的生理生态响应及积累特性

通过盆栽研究了Cd胁迫下德国鸢尾的生长状况、生态效应、生理特性及吸收和富集Cd的能力.结果表明:德国鸢尾对小于5 mg/kg的Cd有较强的耐性,适用于城区土壤修复;Cd浓度大于5 mg/kg时抑制德国鸢尾生长,降低了其生态效应.随着Cd浓度的增大,德国鸢尾根系活力、叶绿素含量和含水量逐渐降低,游离脯氨酸和可溶性糖含量先升高后降低,细胞膜透性逐渐升高.Cd在德国鸢尾体内分布为根系＞地上部分,随着Cd浓度的增大,德国鸢尾根系和地上部分Cd积累浓度逐渐升高、富集系数和转运系数逐渐降低;Cd浓度为20 mg/kg时德国鸢尾对Cd的积累量最大,为2.122 mg/plant.     

鸢尾属部分植物种质资源的RAPD分析

采用RAPD分子标记技术,从100个随机引物中筛选出多态性强、重复性好且稳定性高的引物18个,对38份野生鸢尾属材料进行扩增,共扩增出409条带,其中多态性带405条,多态性比率为99.0%,表明野生鸢尾属植物种间有丰富的遗传多态性;根据DNA谱带计算物种间遗传距离,聚类分析结果将鸢尾属38份材料划分为6组,其结果与传统生物学特性划分的6个亚属的分类结果基本一致;物种特有RAPD标记分析表明,利用18个引物可以较好地将鸢尾属38种植物区分开,其中9个材料得到了单一标记的扩增带,表明运用RAPD分子标记对研究鸢尾属植物特异性基因及标记的筛选等有一定的理论和实际应用价值。     

鸢尾属植物的传粉者吸引及异交策略

已知鸢尾属（Iris）植物约有280种且花部特征多变,具有较高的科研和观赏价值。尽管该属植物具备一定的克隆和自交繁殖能力,但传粉者介导的异交仍在其物种和遗传多样性的维持中发挥重要作用,然而目前仍缺乏对该属植物传粉者吸引及异交策略的系统性总结。本文首先简述了鸢尾属植物的传粉者种类及其适应动物传粉的花部构造,以明确其动物传粉概况。在此基础上,详细论述了该属植物如何通过视觉和嗅觉信号呈现花粉、花蜜和热量报酬供给等策略,实现对传粉者的有效吸引。在传粉者访问前后,鸢尾属植物还可通过合理的花展示、单花内雌雄功能的时空隔离以及传粉后的调控以实现最大程度的异交。此外,影响其传粉者吸引及异交的第三方生物和非生物因素,如食花者和资源配置,也应受到重视。今后随着相关研究的深入和技术手段的革新,研究者应针对鸢尾属植物传粉的热点或有争议的问题,采用花信号定量测定及异交率分子检测等先进技术,通过大范围的对比研究,深入揭示鸢尾属植物与传粉者的互作模式及其繁殖策略。     

云南鸢尾属一新种

报道了鸢尾属植物一新种,即哈巴鸢尾(Iris habanesis X. D. Dong)。该种以植株矮小,花茎单一不分枝,具鸡冠状附属物与尼泊尔鸢尾不同,同时又以花期花茎长15~20 cm而与高原鸢尾有所不同。     

Phylogeny of Iris based on chloroplast matK gene and trnK intron sequence data

Phylogenetic analyses of 46 species of Iris, representing all subgenera and all sections except Regelia, Brevituba, and Monolepis, utilized matK gene and trnK intron sequence data. Sequence data show that Iris is paraphyletic because Belamcanda chinensis is resolved within the genus. The two largest subgenera, Iris and Limniris, are both resolved as polyphyletic. With the removal of section Hexapogon, subgenus Iris is weakly supported as monophyletic. Relationships within subgenus Limniris are more complex with the subgenus as currently circumscribed representing eight independent origins among the species included in this study. Several potential monophyletic groups are identified including subgenus Scorpiris, series Spuria (subgenus Limniris section Limniris), and a clade of section Limniris species from North America and Asia.     

鸢尾体细胞无性系的建立与变异

本文以德鸢尾,马蔺、拟鸢尾和鸢等几种宿根鸢尾为试验材料,通过花器培养建立了体细胞无性系,在多次继代培养过程中,研究了离体培养对鸢尾体细胞无性系变异的影响,并运用聚丙烯酰胺凝胶垂直板电泳技术分析了试管苗叶片的过氧化物酶同工酶。结果表明离体培养已经改变了鸢尾的遗传基础,但在形态特征、生态习性及观赏性状等方面未发生明显的表型变异。     

Histochemical Study of Xylem Cells in In Vitro Culture of Iris sibirica L.

In this study, lignin content data are presented for annual regenerant Iris sibirica plants, comparable to those in six-year-old intact plants. The structure of the shoots of Iris sibirica grown on artificial nutrient media was studied by the histochemical method. Features of the formation of the xylem in Iris sibirica on artificial nutrient media were revealed. Regenerants very quickly developed a complex system consisting of vascular bundles containing sieve tubes, vessels and tracheids, and hydrocyte systems. Hydrocytes of Iris sibirica were tracheids with lignified thickening, but, in contrast to tracheids and vessels of xylem (they are formed based on procambium or cambium—special lateral primary or secondary meristem), hydrocytes differentiated from the cells of permanent tissues (like phellogen), which probably possessed meristematic activity at the time of differentiation. In Iris sibirica hydrocytes covered the vascular bundle by the thick layer and strung along it up to a certain height. High lignin content in young regenerant Iris sibirica plants was due to the formation of the dense tissue from lignified tracheal elements. The study of the differentiation of xylem elements under controlled conditions can serve as a model for our understanding of wood formation processes.

     

Anti-hemostatic effects of a serpin from the saliva of the tick Ixodes ricinus

Serpins (serine protease inhibitors) are a large family of structurally related proteins found in a wide variety of organisms, including hematophagous arthropods. Protein analyses revealed that Iris, previously described as an immunomodulator secreted in the tick saliva, is related to the leukocyte elastase inhibitor and possesses serpin motifs, including the reactive center loop (RCL), which is involved in the interaction between serpins and serine proteases. Only serine proteases were inhibited by purified recombinant Iris (rIris), whereas mutants L339A and A332P were found devoid of any protease inhibitory activity. The highest Ka was observed with human leukocyte-elastase, suggesting that elastase-like proteases are the natural targets of Iris. In addition, mutation M340R completely changed both Iris substrate specificity and affinity. This likely identified Met-340 as amino acid P1 in the RCL. The effects of rIris and its mutants were also tested on primary hemostasis, blood clotting, and fibrinolysis. rIris increased platelet adhesion, the contact phase-activated pathway of coagulation, and fibrinolysis times in a dose-dependent manner, whereas rIris mutant L339A affected only platelet adhesion. Taken together, these results indicate that Iris disrupts coagulation and fibrinolysis via the anti-proteolytic RCL domain. One or more other domains could be responsible for primary hemostasis inhibition. To our knowledge, this is the first ectoparasite serpin that interferes with both hemostasis and the immune response.     

Positive selection of Iris, a retroviral envelope-derived host gene in Drosophila melanogaster

Eukaryotic genomes can usurp enzymatic functions encoded by mobile elements for their own use. A particularly interesting kind of acquisition involves the domestication of retroviral envelope genes, which confer infectious membrane-fusion ability to retroviruses. So far, these examples have been limited to vertebrate genomes, including primates where the domesticated envelope is under purifying selection to assist placental function. Here, we show that in Drosophila genomes, a previously unannotated gene (CG4715, renamed Iris) was domesticated from a novel, active Kanga lineage of insect retroviruses at least 25 million years ago, and has since been maintained as a host gene that is expressed in all adult tissues. Iris and the envelope genes from Kanga retroviruses are homologous to those found in insect baculoviruses and gypsy and roo insect retroviruses. Two separate envelope domestications from the Kanga and roo retroviruses have taken place, in fruit fly and mosquito genomes, respectively. Whereas retroviral envelopes are proteolytically cleaved into the ligand-interaction and membrane-fusion domains, Iris appears to lack this cleavage site. In the takahashii/suzukii species groups of Drosophila, we find that Iris has tandemly duplicated to give rise to two genes (Iris-A and Iris-B). Iris-B has significantly diverged from the Iris-A lineage, primarily because of the "invention" of an intron de novo in what was previously exonic sequence. Unlike domesticated retroviral envelope genes in mammals, we find that Iris has been subject to strong positive selection between Drosophila species. The rapid, adaptive evolution of Iris is sufficient to unambiguously distinguish the phylogenies of three closely related sibling species of Drosophila (D. simulans, D. sechellia, and D. mauritiana), a discriminative power previously described only for a putative "speciation gene." Iris represents the first instance of a retroviral envelope-derived host gene outside vertebrates. It is also the first example of a retroviral envelope gene that has been found to be subject to positive selection following its domestication. The unusual selective pressures acting on Iris suggest that it is an active participant in an ongoing genetic conflict. We propose a model in which Iris has "switched sides," having been recruited by host genomes to combat baculoviruses and retroviruses, which employ homologous envelope genes to mediate infection.     

Iris: Interactive all‐in‐one graphical validation of 3D protein model iterations

Iris validation is a Python package created to represent comprehensive per‐residue validation metrics for entire protein chains in a compact, readable and interactive view. These metrics can either be calculated by Iris, or by a third‐party program such as MolProbity. We show that those parts of a protein model requiring attention may generate ripples across the metrics on the diagram, immediately catching the modeler's attention. Iris can run as a standalone tool, or be plugged into existing structural biology software to display per‐chain model quality at a glance, with a particular emphasis on evaluating incremental changes resulting from the iterative nature of model building and refinement. Finally, the integration of Iris into the CCP4i2 graphical user interface is provided as a showcase of its pluggable design.     

内蒙古野生马蔺种质农艺性状遗传多样性研究

以收集自内蒙古11个盟市的20个野生马蔺种质材料为研究对象,通过对其13个农艺性状指标进行主成分分析、相关性分析和聚类分析,探讨不同种质间的亲缘关系、遗传变异特性及其原因,为马蔺的开发利用、资源保护和育种应用提供理论依据。结果表明:(1)不同来源的马蔺种质农艺性状表现出不同程度的变异性,变异系数范围为9.72%~300.00%,变异系数较大的性状是千粒重、胚长和发芽率,变异系数较小的性状是株高和叶宽。(2)千粒重、发芽率、吸水率、胚长、胚乳长、种子长、生殖枝数、营养枝数、叶宽、株高10个主要性状是引起不同来源马蔺种质农艺性状分化的主要指标。(3)各农艺性状间存在不同程度的相关性,经度、纬度、海拔高度是引起马蔺种质变异的主要因素,胚长、千粒重、吸水率易受生态环境因子的影响。(4)来源不同的20个马蔺种质聚为4类,绝大多数种质材料表现出明显的地域性,经、纬度相近或小生境相似的种质聚为一类。     

鸢尾科药用根茎类16种植物的异黄酮含量测定

鸢尾科药用根茎类１６种植物的异黄酮含量测定秦民坚王强巫弘罡徐国钧（中国药科大学,南京２１００３８）田中俊弘（岐阜药科大学,日本国岐阜市５０２）Ｄｅｔｅｒｍｉｎａｔｉｏｎｏｆｉｓｏｆｌａｖｏｎｅｓｉｎ１６ｓｐｅｃｉｅｓｏｆｒｈｉｚｏｍａｔｏｕｓｍｅｄｉ...     

鸢尾属植物种子休眠研究进展

鸢尾属(Iris L.)花卉具有较高的观赏性,极具开发利用价值,且主要以种子繁殖后代;但多数种子具有休眠特性,给育种工作带来了困难。其休眠原因包括种皮机械阻碍和种子中萌发抑制物存在等内外多重因素,单一或交互作用影响种子萌发。种子休眠解除的方法主要有环境条件处理、机械处理、化学试剂或激素处理等。本文对鸢尾属植物种子休眠原因、休眠解除方法及其机理等作了系统概述,旨在为鸢尾属花卉资源的合理开发利用及种质创新提供理论依据。     

CyberKnife MLC-based treatment planning for abdominal and pelvic SBRT: Analysis of multiple dosimetric parameters,overall scoring index and clinical scoring

PurposeThis study evaluated the plan quality of CyberKnife MLC-based treatment planning in comparison to the Iris collimator for abdominal and pelvic SBRT. Multiple dosimetric parameters were considered together with a global scoring index validated by clinical scoring.Methods and materialsIris and MLC plans were created for 28 liver, 15 pancreas and 13 prostate cases including a wide range of PTV sizes (24–643 cm³). Plans were compared in terms of coverage, conformity (nCI), dose gradient (R50%), homogeneity (HI), OAR doses, PTV gEUD, MU, treatment time both estimated by TPS (t_TPS) and measured. A global plan quality score index was calculated for IRIS and MLC solutions and validated by a clinical score given independently by two observers.ResultsCompared to Iris, MLC achieved equivalent coverage and conformity without compromising OAR sparing and improving R50% (p < 0.001). MLC gEUD was slightly lower than Iris (p < 0.05) for abdominal cases. MLC reduced significantly MU (−15%) and t_TPS (−22%). Time reduction was partially lost when measured. The global score index was significantly higher for MLC solutions which were selected in 73% and 64% of cases respectively by the first and second observer.ConclusionIris and MLC comparison was not straightforward when based on multiple dosimetric parameters. The use of a mathematical overall score index integrated with a clinical scoring was essential to confirm MLC plans advantages over Iris solutions.     

Isoflavones of two Iris species

Analysis of the methanol extracts of the rhizomes of Iris milesii resulted in the isolation of a new isoflavone, 5,6,7,4′-tetrahydroxy-3′-methoxyisoflavone and that of Iris kumaonensis, iriskumaonin methyl ether, iriskumaonin, irisflorentin, junipegenin-A, irigenin and iridin.