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141.
The diploid Oryza species with C-genome type possesses abundant genes useful for rice improvement and provides parental donors of many tetraploid species with the C-genome (BBCC,CCDD).Despite extensive studies,the phylogenetic relationship among the C-genome species and the taxonomic status of some taxa remain controversial.In this study,we reconstructed the phylogeny of three diploid species with C-genome (Oryza officinalis,O.rhizomatis,and O.eichingeri) based on sequences of 68 nuclear single-copy genes.We obtained a fully resolved phylogenetic tree,clearly indicating the sister relationship of O.officinalis and O.rhizomatis,with O.eichingeri being the more divergent lineage.Incongruent phylogenies of the C-genome species found in previous studies might result from lineage sorting,introgression/hybridization and limited number of genetic markers used.We further applied a recently developed Bayesian species delimitation method to investigate the species status of the Sri Lankan and African O.eichingeri.Analyses of two datasets (68 genes with a single sample,and 10 genes with multiple samples) support the distinct species status of the Sri Lankan and African O.eichingeri.In addition,we evaluated the impact of the number of sampled individuals and loci on species delimitation.Our simulation suggests that sampling multiple individuals is critically important for species delimitation,particularly for closely related species. 相似文献
142.
Semple G Ren A Fioravanti B Pereira G Calderon I Choi K Xiong Y Shin YJ Gharbaoui T Sage CR Morgan M Xing C Chu ZL Leonard JN Grottick AJ Al-Shamma H Liang Y Demarest KT Jones RM 《Bioorganic & medicinal chemistry letters》2011,21(10):3134-3141
We herein outline the design of a new series of agonists of the pancreatic and GI-expressed orphan G-protein coupled receptor GPR119, a target that has been of significant recent interest in the field of metabolism, starting from our prototypical agonist AR231453. A number of key parameters were improved first by incorporation of a pyrazolopyrimidine core to create a new structural series and secondly by the introduction of a piperidine ether group capped with a carbamate. Chronic treatment with one compound from the series, 3k, showed for the first time that blood glucose and glycated hemoglobin (HbA1c) levels could be significantly reduced in Zucker Diabetic Fatty (ZDF) rats over several weeks of dosing. As a result of these and other data described here, 3k (APD668, JNJ-28630368) was the first compound with this mechanism of action to be progressed into clinical development for the treatment of diabetes. 相似文献
143.
Sulphate is a major macronutrient required for the synthesis of the sulphur (S)-containing amino acid cysteine and thus is
critical for cellular metabolism, growth and development and response to various abiotic and biotic stresses. A recent genome-wide
expression study suggested that several auxin-inducible genes were up-regulated by S deficiency in Arabidopsis. Here, we examined
the relationship between auxin signaling and S deficiency. Investigation of DR5::GUS expression patterns indicates that auxin accumulation and/or response is suppressed by S deficiency. Consistently, S deficiency
resulted in the suppression of lateral root development, but the axr1-3 mutant was insensitive to this response. Furthermore, the activation of the promoter for the putative thioglucosidase gene
(At2g44460) by S deficiency was suppressed by auxin, cytokinin and abscisic acid (ABA). Interestingly, the activation of At2g44460
by S deficiency is regulated by the availability of carbon and nitrogen nutrients in a tissue-specific manner. These results
demonstrate that auxin plays a negative role in signaling to S deficiency. Given that activation of the genes encoding the
sulphate transporter SULTR1;2 and 5′-adenylylsulphate reductase APR2 are suppressed by cytokinin only, we hypothesize that
while cytokinin may play an important role in general S deficiency response, auxin might be only involved in a subset of S
deficiency responses such as the release of thiol groups from the S storage sources.
Electronic Supplementary Material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
144.
Over the past ten years there have been a large number of publications that have described hundreds of quantitative trait
loci (QTL) in livestock species. To facilitate the comparison of QTL results across experiments, the Animal QTL database (QTLdb)
was developed to house all published QTL information as a public repository. The QTLdb was originally developed to serve the
porcine genomics community (previously known as PigQTLdb). We have further developed the QTLdb to house QTL data from multiple
species, including but not limited to cattle, chickens, and pigs. In addition, tools have been developed to allow QTL map
alignments against consensus linkage maps, radiation hybrid (RH) maps, BAC fingerprinted contig (FPC) maps, single nucleotide
polymorphism (SNP) location maps, and human maps. In addition, we have expanded the capabilities of the database such that
research tools were developed where “private” preliminary QTL data could be entered and compared against all public data.
This allows researchers to visualize data before publication and compare it with published results to aid in data interpretation.
To serve this purpose, the database curator/editor tools also include functions that allow registered users to enter their
own QTL data, make use of the QTLdb tools for data analysis, and use the QTLdb as a publishing tool (URL:
). 相似文献
145.
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147.
In a survey of endophytic fungi associated with medicinal plants in Beijing, two new records, Phoma jolyana and Microsphaeropsis conielloides, were isolated from Eucommia ulmoides Oliv., Forsythia giraldiana Lingelsh., E suspensa (Thunb.) Vahl, E suspensa 'duanzhi', Rhus potaninii Maxim. and Berberis poiretii Schneid. These fungi are redescribed and illustrated in this paper. 相似文献
148.
针对环境因子与草原植物叶绿素含量的联动是否关系到植物生活型优势的问题, 该研究以锡林浩特典型草原为研究区, 选取2020年7月实测的11个样地50种植物共185个牧草样品的叶绿素含量, 运用相关分析、单因素方差分析、冗余分析(RDA)、逐步回归分析和通径分析等方法, 系统性地分析了多环境因子对草原植物不同生活型叶绿素指标的影响, 进而分析植物竞争优势形成的潜在驱动机制。研究结果表明: 1)典型草原区植物叶绿素a、叶绿素b含量均与总叶绿素含量呈极显著正相关关系, 相关系数分别为0.807和0.936, 草原植物总叶绿素含量受叶绿素b含量的影响程度更大; 2)草原植物4类生活型的叶绿素a、叶绿素b和总叶绿素含量均为小/半灌木>多年生禾草>一/二年生植物>多年生杂类草; 3)环境因子对植物生活型叶绿素含量的解释程度存在差异, RDA显示环境因子对小/半灌木的叶绿素含量解释程度最大(28.0%), 其次为一/二年生植物(18.3%)和多年生杂类草(17.7%), 多年生禾草各项叶绿素指标的解释度最低(12.7%); 4)植物生活型各叶绿素指标受多种环境因子的影响, 回归分析显示小/半灌木的叶绿素b含量受到土壤有机碳含量和大气相对湿度的影响, 总叶绿素含量主要受到大气相对湿度的影响, 多年生杂类草叶绿素b含量主要受到地表温度的影响, 一/二年生植物的叶绿素a、叶绿素b、总叶绿素含量主要受到土壤pH的影响; 5)在草原生境中, 通径分析的综合研究显示植物叶绿素a含量主要受到土壤环境因子的影响, 植物叶绿素b和总叶绿素含量主要受到大气环境因子的影响, 相比较而言, 多年生禾草不易受环境因子的牵动, 成为更能忍受外界环境变化的植物种类, 因此, 在群落演替进化中这类植物逐渐占据优势地位。 相似文献
149.
对233份河南省地方花生资源进行了蛋白质含量、含油量、油酸和亚油酸含量的全面测定,并与省外和国外资源的相关性状进行了比较分析。在河南地方品种资源中,蛋白质含量中等,平均含油量和油酸含量相对较高,但缺乏蛋白质含量超过30%或含油量超过56%、油酸含量超过70%的突出材料。河南省目前高油品种选育有明显进展,育成了一批高油花生品种,但育成品种蛋白质含量普遍偏低。提出了充分利用现有地方品种资源,积极采用远缘杂交、诱变、分子标记辅助选择技术及现代基因工程技术创制优良种质,选育优质专用品种的育种策略。 相似文献
150.
目的:寻找一种新型的转染效率高,毒性低的非病毒基因载体.方法:通过化学方法合成Polyimine-MPEI,然后以不同质量比包裹绿色荧光蛋白质粒,检测在COS-7细胞中的转染效率和毒性.结果:在比例从5到100之间,转染效率均比较理想,能达到1.00E+07以上,Polyimine-MPEI的毒性也很小,细胞的生长率均在80%以上,明显高于PEI25KDa对照组.结论:Polyimine-MPEI是一个很有研究前景的聚合物载体,具有高转染效率低毒性的特点,可以通过延长反应时间,增加分子量,增大转染能力. 相似文献