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关键词： 氨基酸   吸收和转运   氮素营养   信号分子   胁迫响应  

摘要： 氨基酸不仅是细胞中蛋白质生物合成的必需底物,而且也参与植物体内的氮代谢途径以及碳氮平衡的调节。近年来,氨基酸的转运与吸收机制及其生物学功能已成为植物分子生物学特别关注和研究的热点之一。最近,学术界亦发现某些氨基酸可能作为信号分子对植物生长发育具有特殊的生物学意义。本文就氨基酸吸收与转运的分子生理机理及其在植物生长发育中的重要功能(如调控生长、适应各种环境胁迫等)的研究进展进行了较详细地综述。

关键词： 海峡两岸   植物分子生物学   生物技术   研究进展   合作机制  

摘要： 介绍了海峡两岸应用植物分子生物学与生物技术的理论与方法,在农业科学与植物科学方面所取得的不菲成果以及相应的社会经济效益。在竞争日益激烈的国际环境形势下,海峡两岸应该从多层次加强交流与合作,为发展高效优质与环境友好型农业、开发新型能源植物与工业原料、提供健康食品与新型药物等方面提供新的思路与技术,并为海峡两岸社会经济的可持续发展做出贡献。

关键词： PHYTOPLASMAS   INSECTS as carriers of disease   PLANT-pathogen relationships   PATHOGENIC bacteria   INSECTS -- Pathogens   TRANSCRIPTION factors   PLASMIDS  

摘要： Phytoplasmas are bacterial pathogens of plants that are transmitted by insects. These bacteria uniquely multiply intracellularly in both plants (Plantae) and insects (Animalia). Similarly to bacterial endosymbionts, phytoplasmas have reduced genomes with limited metabolic capabilities. Nonetheless, the chromosomes of many phytoplasmas are rich in repeated DNA consisting of mobile elements. Phytoplasmas produce an arsenal of effectors most of which are encoded on these mobile elements and on plasmids. These effectors target conserved plant transcription factors resulting in witches' broom and leafy flower symptoms and suppression of plant defense to insect vectors that transmit the phytoplasmas. Future studies of these fascinating microbes will generate a wealth of new knowledge about forces that shape genomes and microbial interactions with multicellular hosts.

ISBN: (纸本)9787040351552

关键词： DOMESTICATION of animals   SYSTEMS biology   BOTANICAL chemistry   HYDRA (Marine life)   ENZYMES   MOLECULAR biology  

摘要： Specialized (traditionally called 'secondary') metabolism can be thought of as a hydra with hundreds of thousands of compounds produced by thousands of enzymes across the entire plant kingdom. Until recently, plants that produce the most interesting and valuable metabolites were recalcitrant to modern molecular biology approaches for gene and pathway discovery. Recent advances in technologies for genomic, transcriptomic, proteomic, and metabolonnic methods now allow for deployment of 'systems biology' approaches to help elucidate unknown steps in specialized metabolite pathways, for example through co-expression analyses. Inexpensive transcriptome and whole genome sequencing (WGS) promises to provide direct access to metabolic pathways in plants not currently used as reference organisms. For example, WGS has uncovered cases of physical proximity of genes of specialized metabolism. Further integration of multiple 'omics' datasets through advances in bioinformatics tools will increase our knowledge of pathway architecture and regulation at an ever-increasing rate. As such the era of systems biology is rapidly providing a broader and deeper understanding of plant specialized metabolism.

关键词： malaria   antimalarial plants   in vitro antimalarial activity   Costa Rican plants   Plasmodium berghei  

摘要： Treatment with the usual antimalarial drugs, have induced parasite resistance, reinforcing the need to finding natural antimalarial components that would be found on plants from the forest. Therefore, we decided to look for these components in Costa Rican plants from a protected forest area. Fresh and dry extracts of roots, bark, leaves, flowers and fruits of 25 plants from a biological reserve in Costa Rica, Reserva Biologica Alberto Manuel Brenes (REBAMB), were studied in vitro for the presence of substances with antimalarial activity. By studying the inhibition of P. berghei schizogony, we assessed the antimalarial activity of several plant extracts: Aphelandra aurantiaca, A. tridentata (Acanthaceae);Xanthosoma undipes (Araceae);Iriartea deltoidea (Arecaceae);Neurolaena lobata (Asteraceae);Senna papillosa, Pterocarpus hayessi, Lonchocarpus pentaphyllus (Fabaceae);Nectandra membranacea, Persea povedae, Cinamomum chavarrianum (Lauraceae);Hampea appendiculata (Malvaceae);Ruagea glabra, Guarea glabra (Meliaceae);Psidium guajava (Myrtaceae);Bocconia frutescens (Papaveraceae);Piper friedrichsthalii (Piperaceae);Clematis dioica (Ranunculaceae);Prunus annularis (Rosaceae);Siparuna thecaphora (Siparunaceae);Solanum arboreum, Witheringia solanacea (Solanaceae);Ticodendrum incognitum (Ticodendraceae);Heliocarpus appendiculatus (Tiliaceae) and Myriocarpa longipes (Urticaceae). We used different parts of the plants as well as fresh and dried extracts for testing IC50. The solid content of the extracts ranged from 1-71.9 mu g/mL. The fresh extracts showed stronger activity than the dry ones. Since the plants showing the strongest antimalarial activity are very common in Central America, and some similar genera of these plants have shown positives results in South America, we considered important to present these findings for discussion. On the other hand, this is the first systematic study of this kind ever realized in a circumscribed and protected area of Costa Rica.

关键词： CYTOSKELETON   CELL compartmentation   PLANTS  

摘要： An introduction is presented in which the editor discusses various reports within the issue on topics including control of plant architecture using cytoskeleton, impacts of cellular compartmentalization and development by signals of plants.

关键词： Chromolaena odorata   Soluble P   Exchangeable bases   Earthworms   Soil enzymatic activities   Guinea savannas  

摘要： This paper attempts to provide a new perception of the weed Chromolaena odorata (Asteraceae) which is considered as a plague in agriculture or as a soil fertility indicator. The study was conducted in the forest-savanna transition zone of Cte d'Ivoire and aimed to compare soil biological activity and plant nutrient availability under three well-represented vegetation features, including C. odorata lands (ChrO), shrub savannas (ShrS), and grass savannas (GraS). Each of these vegetation features included five plot replicates (50 m x 50 m size) distributed in the landscape. Soil chemical parameters such as pH, organic matter, soluble phosphorus, exchangeable bases, and biological parameters such as abundance and diversity of earthworms, and soil enzymatic activities were investigated. Composite soil samples were collected and analyzed for chemical and microbial parameters while earthworms were sampled using the Tropical Soil Biology and Fertility 25 x 25 x 30 cm soil monolith method. A principal component analysis showed a clear demarcation between C. odorata plots and the savanna ones. Soluble P and exchangeable bases were significantly higher under ChrO than under both savannas. Earthworm density was twice higher under ChrO (433.3 +/- A 90.8 ind m(-2)) than under ShrS (173.9 +/- A 61.5 ind m(-2)) and GraS (176.0 +/- A 40.6 ind m(-2)) and this was accounted for by the abundance of detritivores and polyhumics. Acid and alkaline phosphatase activities under ChrO (2.9 +/- A 0.2 and 2.5 +/- A 0.3 mu mol pNP g(-1) soil h(-1), respectively) were twice higher than under both savannas. Based on the fact that ChrO and ShrS were located on similar soil types and had the same topographic position, we concluded that the establishment of C. odorata in a savanna land and its subsequent high biomass and quality-litter production were mostly the reasons of the improvement in soil biology and plant nutrient availability. Between-savanna comparison showed that ShrS, with higher CEC and

关键词： 体细胞胚胎发生受体类蛋白激酶   膜富亮氨酸重复序列受体类蛋白激酶   生物功能  

摘要： 体细胞胚胎发生受体类蛋白激酶(Somatic embryogenesis receptor-like kinases,SERKs)属于膜富亮氨酸重复序列受体类蛋白激酶(Leucine-rich repeat sequence receptor-like kinase,LRR-RLK)家族的第二亚类。SERK具有典型的胞外信号受体结构域、跨膜结构域和胞内激酶活性结构域,研究发现SERKs在植物生命活动中承担着多个角色。文章简述了SERKs的典型结构域特征,重点介绍该类蛋白在体细胞胚发生、生殖发育、激素感应和病理反应方面发挥的功能,同时对该蛋白激酶的研究价值和应用前景进行了探讨。

关键词： P/O值   传粉生物学   繁育系统   桂林小花苣苔   阳朔小花苣苔  

摘要： 通过野外观察和室内试验,对两种广西特有的桂林小花苣苔和阳朔小花苣苔的传粉生物学进行比较研究。结果表明:两种报春苣苔属植物花期从7月底至8月初;单花花期内花粉具有较高的活性,最高可达92.6%和94.5%;柱头可授性最高时可达90%和95%;花粉/胚珠比率(P/O)分别为110.28±17.45和229.65±18.00;柱头与花药之间存在着空间隔离,可防止自花授粉;在单花花冠裂片张开后第3天,花药开始散粉,但雌蕊在花朵刚开始开放时已伸长,待第3天时柱头已伸长到位于花冠筒口部,高于花药,便于接受异花花粉;该两种植物均不存在无融合生殖现象;两种报春巨苔属植物均高度自交亲和,但很难发生自发的自花授粉,必须依靠外力,因此传粉媒介对于结实率有重要影响,自然条件下基本不发生自花授粉;在自然状态下结实率明显低于两种人工授粉的结实率;小蜂和淡脉隧蜂是目前已知仅见的两种传粉者。