921 resultados para phylogeny, bullfinches, Pyrrhula, molecular genetics, morphology, biogeography


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稻属Oryza隶属禾本科Poaceae,包括20多个野生种和2个栽培种(亚洲栽培稻O. sativa L和非洲栽培稻O. glaberrima Steud) ,广泛分布于全球热带和亚热带。稻属物种可划分为10个基因组(又称染色体组)类型:A, B, C, BC, CD, E, F, G, HJ 和 HK。栽培稻所属的A基因组是稻属中物种数目最多、地理分布最广的基因组类型,由8个种组成。由于栽培稻属于A基因组,故A基因组物种是栽培稻遗传改良的巨大基因源。数十年来,国际上许多学者对A基因组类群开展了大量涉及形态、细胞、同工酶和分子标记方面的研究,但由于A基因组物种间遗传关系十分接近,形态上差异小且地理分布重叠,使得A基因组物种的系统发育、物种起源和生物地理学等方面存在诸多悬而未决的问题,是稻属中分类和鉴定困难较多的类群。本文利用核基因内含子序列,结合转座子插入分析,重建了A基因组的系统发育,估测了各类群的分化时间;与此同时,基于多克隆测序和基因谱系分析,探讨了O. rufipogon和O. nivara遗传关系以及亚洲栽培稻起源。主要研究结果如下: 1. A基因组的系统发育 在水稻全基因组数据库搜索的基础上,测定了4个单拷贝核基因(Adh1 及3个未注释基因)的内含子序列,构建了稻属A基因组8个种的系统发育关系。基于最大简约法和贝叶斯法的系统发育分析表明:1)澳大利亚的O. meridionalis为A基因组的基部类群;2)亚洲栽培稻两个亚种O. sativa ssp. japonica 和 O. sativa ssp. indica分别和不同的野生类群聚为独立的两个分支,支持japonica 和 indica为多次起源;3)O. rufipogon和O. nivara在系统发育树上完全混在一起,显示出二者间不存在遗传分化;4)非洲一年生野生种O. barthii是非洲栽培稻O. glaberrima的祖先,而非洲多年生野生种O. longistaminata与O. glaberrima/O. barthii.亲缘关系较远;5)分子钟方法估测A基因组类群约在2百万年前(2.0MYA)开始分化,亚洲栽培稻和非洲栽培稻,以及亚洲栽培稻的两个亚种则分别在0.7和 0.4 MYA左右开始分化。此外,通过核基因内含子序列与其它常用片段如ITS,matK等对比分析表明,进化速率相对较快的核基因内含子序列可以有效地用于近缘类群的系统发育研究。 2. Oryza rufipogon 和O. nivara群体遗传研究及亚洲栽培稻起源 对于亚洲野生类群O. rufipogon和O. nivara是合并为一个种还是处理为两个独立的种一直存在争议。在系统发育研究基础上,我们选取4个核基因内含子或5’-UTR区(Waxy, LHS,CatA和1个未注释基因),对采自整个分布区的群体样品进行了多克隆测序,结果表明:1)检测到O. rufipogon和O. nivara均有较高的核苷酸多态性,4个位点上π值和θw值平均分别为0.011和0.014;2)且二者在遗传上没有明显分化,两个类群在4个核基因位点上均检测到大量共享多态(shared polymorphism),未发现固有差异(fixed difference),表明它们历史上可能属于一个大群体,支持将二者作为种内不同生态型或亚种处理;3)基因谱系树表明亚洲栽培稻的两个亚种indica和japonica分别和不同的O. rufipogon (包括O. nivara)群体聚在一起,进一步从基因谱系角度支持亚洲栽培稻多次起源假说。 3.转座子在群体遗传与系统发育研究中的应用 鉴于目前植物谱系地理学研究中缺乏具有足够信息量的分子标记用于检测种内遗传变异,我们选取3个核基因中的转座子,通过对取自O. rufipogon和O. nivara整个分布区的37份样品的克隆测序,探讨了进化速率快、信息含量丰富的转座子序列在群体遗传上的应用。结果表明:1)无论在物种水平还是群体水平,转座子能检测到比包括内含子在内的其它DNA区域高得多的遗传变异;2)在物种水平上,异交多年生的O. rufipogon和自交一年生的O. nivara多样性均较高,且2个种间相差很小,二者在3个位点上平均核苷酸多样性π值均为0.013,差别主要表现在O. rufipogon杂合位点比例(46.1%)明显高于O. nivara(9.1%),说明交配系统不同并不一定和物种多样性水平相关;3)是否发生转座子序列插入是有价值的系统发育信息,发生在不同染色体上3个基因中的转座子插入进一步证实A基因组基部类群是O. meridionalis;通过叶绿体中3个转座子的插入现象推断了稻族一些四倍体物种,如稻属BC基因组的一些类群的母本来源。

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云杉属植物是非常重要的森林树种,广泛分布于北半球的寒温带、温带高山和亚高山地带。该属为松科中仅次于松属和冷杉属的第三大属,约有 28-56 种。自云杉属建立以来,其属于松科没有任何疑议。然而,由于云杉属物种间频繁杂交、形态趋同和取样困难,尽管已经有基于形态学、细胞学、化学成份、叶绿体 DNA RFLP 等方面的研究,该属的属下分类仍然存在诸多争议。本文利用父系遗传的叶绿体基因和母系遗传的线粒体基因序列重建了云杉属的系统发育关系,探讨了云杉属生物地理格局的形成过程。在此基础上,我们研究了低拷贝核 CAD 基因在云杉属的进化式样。另外,我们还对裸子植物线粒体基因 rps3 的内含子分布和进化进行了初步研究。 1. 云杉属的系统发育和生物地理学研究 我们选择了 Farjon (1990) 确定的 34 个种中的 33 种 (另一个种在 Flora of China 未得到承认),共 103 个个体,对这些个体的叶绿体 DNA 片段 trnC-trnD 和 trnT-trnF 以及线粒体基因 nad5 的第一个内含子进行了序列测定。在两个叶绿体基因片段联合分析构建的系统发育树上,北美西部的 P. breweriana 和 P. sitchensis 位于最基部。其余的物种分为三支:第一支由北美的两个物种组成;第二支包括分布于喜马拉雅-横断山区及其周围地区的八个种、台湾的 P. morrisonicola、西亚的 P. orientalis、日本的两个种及北美的 P. chihuahuana;第三支中,北美的 P. pungens 位于基部,亚洲东北部的种 (除 P. maximowiczii 和 P. torano 外)、P. retroflexa 和欧洲的 P. abies 构成一个单系群,并与北美的 P. mariana 和 P. rubens 及来自巴尔干半岛的 P. omorika 形成姐妹支。所有样品的 nad5 第一个内含子序列可分为 A、B、C、D 和 E 5 种单倍型,北美的物种拥有前 4 种,而且 A、B 和 C 单倍型为北美所特有;欧亚的物种仅含 D 和 E 两种单倍型。 上述结果结合 MacClade 和 DIVA 分析及化石证据,我们推断云杉属起源于北美,至少两次经白令陆桥扩散至亚洲,然后从亚洲扩散至欧洲。亚洲东北部的绝大多数物种和欧洲云杉 P. abies 的种间遗传变异非常低,而且线粒体单倍型均为 D,可能来源于一次近期的辐射分化。云杉属的现代分布中心之一喜马拉雅-横断山区的物种可能不是一次起源,日本的物种同样如此,这可能与第三纪气候变冷和第四纪冰川导致的物种迁移有关。此外,我们发现目前用于云杉属分类的一些形态性状(如叶扁平、菱形等)在系统发育树上位于不同的位置,说明这些性状可能不是一次起源或是祖征在不同支系中的保留,用于云杉属的系统划分须慎重。 2. 云杉属 CAD 基因的进化研究 裸子植物的多倍体特别少,且以基因组庞大而著称。被子植物中的很多单拷贝基因在裸子植物中以低拷贝或多拷贝基因家族的方式存在。CAD 基因在木质素单体合成的最后一步起作用,在松属中只发现了一种 CAD 基因拷贝,在欧洲云杉中却发现了三种拷贝,而且 Southern 杂交和子代分离鉴定结果表明这三种拷贝至少位于两个位点上。然而,对云杉属三个物种 (包括欧洲云杉) 构建的遗传图谱却都只发现了一个 CAD 基因位点。由于云杉属 CAD 基因的数目和分布存在很大争议,我们根据构建的叶绿体基因树,选择了不同支上的 20 个物种、29 个样品研究该基因的进化式样。结果表明:云杉属不同物种中 CAD 基因的拷贝数为 1-4 种,多数为 2-3 种。系统发育分析发现有些物种的所有 CAD 基因拷贝聚成一支,另有一些物种的 CAD 基因拷贝位于不同位置。此外,我们对 GenBank 中云杉属三个物种 CAD 基因的 EST 序列分析后发现:EST 序列的差异主要发生在 3’-UTR 区,表现为序列长短的不同,这有可能是进行体外反转录时引物结合于不同的位置所致。因此,结合前人研究(包括遗传图谱分析),我们推测 CAD 基因在云杉属内发生了多次重复,重复拷贝很可能呈串联排列。 3. 裸子植物线粒体基因 rps3 的进化研究 线粒体基因内含子的获得/丢失已经被广泛应用于系统发育研究。rps3 为分布最广的线粒体核糖体蛋白基因,一般含一个内含子,前人研究显示其在裸子植物中多了一个第二类内含子 rps3i2,并将这个内含子作为区分裸子植物和其它植物类群的标志之一。然而,该研究只选择了苏铁和银杏作为裸子植物的代表,取样代表性不足。在本研究中,我们对裸子植物每个科至少选择一个物种作为代表,通过 DNA 序列和部分物种的 RT-PCR 分析,探讨 rps3 基因在裸子植物中的进化。结果表明 rps3 基因内含子的分布与裸子植物系统发育关系相吻合:Conifer II、松科的落叶松属和黄杉属及百岁兰科不仅不含 rps3i2,而且丢失了第一个内含子;金钱松属缺失第二个内含子。我们推断在 Conifer II 的祖先和百岁兰科中分别一次性丢失了两个内含子;在松科中则发生了两次单独的丢失事件,一次是在落叶松属和黄杉属的祖先中丢失了两个内含子,一次是在金钱松属中丢失了第二个内含子。另外,在 Ephedra 中没有扩增出 rps3 基因,Gnetum 中具有第二个内含子,倪藤科的 rps3i2 似乎支持松科与倪藤纲的关系更近。对 rps3i2 的进一步分析发现,其序列结构与松科的系统发育关系非常吻合。根据上述结果和 mRNA 编辑位点分析,我们认为 Conifer II等类群中的两个rps3内含子丢失可能是反转录酶介导的 cDNA 反转录造成的。Psuedolarix 的内含子丢失也可能为相同机制,但因缺乏材料而未能进一步研究。

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槽舌兰属为(Holcoglossum schltr.)兰科树兰亚科万代兰族指甲兰亚族植物,大部分种类为中国特有种,部分种类分布到越南、泰国、缅甸等国家和地区。本研究利用ITS、trnL-F和matK序列重建了槽舌兰属的系统树,在此基础上对其和植物地理进行了初步探讨并对该属植物的叶表皮特征演化进行了探讨。具体结果如下: 1.槽舌兰的分子系统学研究及分子植物地理学 对槽舌兰属的13个种的12个种进行了取样(H. quasipinifolium未包括),而横断山地区所有已知的槽舌兰属植物的居群进行了取样,共有25个取样代表了槽舌兰属。运用ITS、trnL-F和matK序列重建了槽舌兰属的系统树。槽舌兰属得到了很强的单系支持,并且分为了从南到北的三个分支,其中高山类群得到了很强的支持,尽管该类群内部系统关系没有得到解决。本研究推测槽舌兰属是从南部的热带地区向北部扩散,并在横断山地区辐射分化。槽舌兰高山类群的辐射分化和该地区的迅速隆起密切相关。 2.槽舌兰属的叶表皮演化 在光学显微镜下和电子显微镜下,观察了21个代表槽舌兰属8个种以及5个来自Vanda concolor和 Aerides ordorata的叶表皮样品的常规特征,包括表皮细胞的形状,密度,垂周壁式样,气孔类型,气孔指数,气孔长/宽(L/W), 气孔大小等等。槽舌兰属的气孔除H. omeiense外,其它上、下表皮均有气孔分布,是比较进化的类型。表皮细胞为多边形,垂周壁平直或弓形。槽舌兰属的上表皮细胞都大于下表皮的细胞。与万代兰族的其它类群相似。结果表明,气孔类型和气孔指数与属的系统发育关系一致,可以作为一个很好的特征。 3.槽舌兰属高山组的物种形成初探 槽舌兰属高山组植物在形态上、传粉系统以及生境都有了很大的分化,但该类群在分子序列上却几乎没有区别,本文推测该类群是近期的辐射分化形成的。

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Acipenseriformes is an endangered primitive fish group, which occupies a special place in the history of ideas concerning fish evolution, even in vertebrate evolution. However, the classification and evolution of the fishes have been debated. The mitochondrial DNA (mtDNA) ND4L and partial ND4 genes were first sequenced in twelve species of the order Acipenseriformes, including endemic Chinese species. The following points were drawn from DNA sequences analysis: (i) the two species of Huso can be ascribed to Acipenser; (ii) A. dabryanus is the mostly closely related to A. sinensis, and most likely the landlocked form of A. sinensis; (iii) genus Acipenser in trans-Pacific region might have a common origin; (iv) mtDNA ND4L and ND4 genes are the ideal genetic markers for phylogenetic analysis of the order Acipenseriformes.

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小鲵属为亚洲特有的有尾两栖类,是小鲵科之模式属。现记载小鲵属动物有29种,占全科物种数一半以上(Frost, 2007),为小鲵科第一大属。该属分布跨越古北界和东洋界,分布于中国、朝鲜、韩国、日本等地区,其系统学研究一直以来颇为中外学者所关注。澄清该属的物种分类问题,阐明其种间的系统发育关系对整个小鲵科的系统演化与分布格局关系的研究具有关键性意义。 本论文以中国及周边地区的小鲵属物种为主要对象,主要利用分子生物学实验与生物信息学途径相结合的手段,运用支序系统学与分子进化生物学理论及分析方法,展开系统发育的研究。在此基础上诠释现存的分类问题,并探讨该属系统发育关系。 研究材料上,本研究采用野外采集与网络下载数据相结合的方法,获取了较为全面的小鲵属物种DNA序列资料。技术手段上,选取了线粒体DNA的Cytb、12S、16S、NADH 2、COI等多个基因部分片段序列,对小鲵属开展了较为全面系统的研究。分析方法上,针对小鲵属物种各类群的具体情况,运用了处于领域前沿的多种分析方法。应用PAUP、MrBayes、Modeltest、Mega等软件,采用了最大简约法(MP)、邻接法(NJ)、贝叶斯推断(BI)及K2P遗传距离分析等方法。 本研究对小鲵属进行了较为全面的系统发育研究,弥补了有关小鲵属系统发育研究的不足,并得出了以下结果: (1)关于豫南小鲵Hynobius yunanicus的有效性,基于细胞色素b序列的系统发育关系联合形态和染色体组型等证据证明了豫南小鲵是商城肥鲵的同物异名。 (2)获得了较为全面的小鲵属物种系统发育树,并以此解释了北海道滞育小鲵、东北小鲵、中国小鲵与义乌小鲵等存在的分类问题。 (3)本研究利用DNA条形码技术对小鲵属及小鲵科物种进行了鉴定,再次证明豫南小鲵为商城肥鲵的同物异名;并认为猫儿山小鲵与挂榜山小鲵为同物异名。 综上,本研究较为完整地勾勒了小鲵属的系统发育关系全貌,并对小鲵属物种的起源进行了推测。 Hynobius, the type genus of the Family Hynobiidae, is the only exclusively Asian salamander genus. This genus which contains 29 species (beyond half of total Family), is the key group in Hynobiidae. The genus distributed across Palaearctic and Oriental Realm, and was found in China, Korea, and Japan. Systematics of genus Hynobius draws attention of researchers all the times. Resolving the taxonomic and phynogenetic questions of Hynobius is very important to the evolutionary research of Family Hynobiidae. Firstly, studies on systematics of genus Hynobius based on morphology, karyotype and molecular phylogeny of Hynobius are reviewed along with existing questions of this genus. The sequential reaserch project of phylogenetics is perspectively outlined. Using molecular data, we compared Hynobius yunanicus with a sympatric species Pachyhynobius shangchengensis. Our cytb sequences associating with karyotypic and morphological data supportted that H. yunanicus is not a valid species, but a synonym of P. shangchengensis. Because of phenotypic plasticity, some morphological characters are not even suitable for identifying hynobiids. The taxonomy of hynobiids is still controversial to a certain extent (Zhao et al. 1993; Fei, 1999; Chen et al. 2001; Zeng et al. 2006) and needs to be resolved by a new method. Here we examined the utility of COI barcoding for the discrimination of hynobiids. Meantime, the taxonomy of this Family was looked-over again. Our result show that the DNA Barcoding based on COI is easier and more rapidly than classic methods. And the DNA Barcodes data supported the actual taxonomy of Hynobiidae. Based on the achievements of our research, the phylogeny of Hynobius was reconstructed including some new species (H. maoershanensis, H. guabangshanensis, etc). Besides the phylogenetics of Hynobius was outlined, some questions and the hypothesis about the origin of genus Hynobius was put out.

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The aim of the 5-year European Union (EU)-Integrated Project GEnetics of Healthy Aging (GEHA), constituted by 25 partners (24 from Europe plus the Beijing Genomics Institute from China), is to identify genes involved in healthy aging and longevity, which allow individuals to survive to advanced old age in good cognitive and physical function and in the absence of major age-related diseases. To achieve this aim a coherent, tightly integrated program of research that unites demographers, geriatricians, geneticists, genetic epidemiologists, molecular biologists, bioinfomaticians, and statisticians has been set up. The working plan is to: (a) collect DNA and information on the health status from an unprecedented number of long-lived 90+ sibpairs (n = 2650) and of younger ethnically matched controls (n = 2650) from 11 European countries; (b) perform a genome-wide linkage scannning in all the sibpairs (a total of 5300 individuals); this investigation will be followed by linkage disequilibrium mapping (LD mapping) of the candidate chromosomal regions; (c) study in cases (i.e., the 2650 probands of the sibpairs) and controls (2650 younger people), genomic regions (chromosome 4, D4S1564, chromosome 11, 11.p15.5) which were identified in previous studies as possible candidates to harbor longevity genes; (d) genotype all recruited subjects for apoE polymorphisms; and (e) genotype all recruited subjects for inherited as well as epigenetic variability of the mitochondrial DNA (mtDNA). The genetic analysis will be performed by 9 high-throughput platforms, within the framework of centralized databases for phenotypic, genetic, and mtDNA data. Additional advanced approaches (bioinformatics, advanced statistics, mathematical modeling, functional genomics and proteomics, molecular biology, molecular genetics) are envisaged to identify the gene variant(s) of interest. The experimental design will also allow (a) to identify gender-specific genes involved in healthy aging and longevity in women and men stratified for ethnic and geographic origin and apoE genotype; (b) to perform a longitudinal survival study to assess the impact of the identified genetic loci on 90+ people mortality; and (c) to develop mathematical and statistical models capable of combining genetic data with demographic characteristics, health status, socioeconomic factors, lifestyle habits.

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We discuss recent advances in the diagnosis and management of renal cell cancer (RCC) given the enhanced molecular genetics knowledge in this area. A number of hereditary renal cancer syndromes have been described, including von Hippel-Lindau disease, Birt-Hogg-Dube syndrome, hereditary leiomyomatosis/RCC syndrome, and hereditary papillary renal cancer. Early molecular diagnosis now facilitates the management and prevention of RCC in families. Recommendations for screening in families are discussed. The Oncologist 2010;15:532-538

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Dissertation presented in fulfillment of the requirements for the Degree of Doctor of Philosophy in Biology (Molecular Genetics) at the Instituto de Tecnologia Química e Biológica da Universidade Nova de Lisboa

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The present study Molecular genetic characterization of endemic yellow catfish ,generated an important information on the genetic variation and stock structure of the endangered yellow catfish(Horabagrus brachysoma) endemic to the western Ghats. Three genetically discrete stocks of the species have been identified for the first time using allozymes, RAPD(Random Amplified Polymorphic DNA) and microsatelite markers and it is a significant step towards realizing the goal of management of fishery and conservation of the yellow catfish populations in the rivers of the Western Ghats region. In conclusion genetic markers were found to be powerful tools to analyze the population genetic structure of the yellow catfish. Geographic isolation by land distance,inbreading as a result of over-exploitation etc are some reasons for the genetic differenciation between the pairs and deficiency of hetrozygosity revealed by the two co dominant markers, allozyme, and microsatelites.the study emphasizes the need for stock-wise, propagation assisted-rehabilitation of the natural populations yellow catfish

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El marcaje de proteínas con ubiquitina, conocido como ubiquitinación, cumple diferentes funciones que incluyen la regulación de varios procesos celulares, tales como: la degradación de proteínas por medio del proteosoma, la reparación del ADN, la señalización mediada por receptores de membrana, y la endocitosis, entre otras (1). Las moléculas de ubiquitina pueden ser removidas de sus sustratos gracias a la acción de un gran grupo de proteasas, llamadas enzimas deubiquitinizantes (DUBs) (2). Las DUBs son esenciales para la manutención de la homeostasis de la ubiquitina y para la regulación del estado de ubiquitinación de diferentes sustratos. El gran número y la diversidad de DUBs descritas refleja tanto su especificidad como su utilización para regular un amplio espectro de sustratos y vías celulares. Aunque muchas DUBs han sido estudiadas a profundidad, actualmente se desconocen los sustratos y las funciones biológicas de la mayoría de ellas. En este trabajo se investigaron las funciones de las DUBs: USP19, USP4 y UCH-L1. Utilizando varias técnicas de biología molecular y celular se encontró que: i) USP19 es regulada por las ubiquitin ligasas SIAH1 y SIAH2 ii) USP19 es importante para regular HIF-1α, un factor de transcripción clave en la respuesta celular a hipoxia, iii) USP4 interactúa con el proteosoma, iv) La quimera mCherry-UCH-L1 reproduce parcialmente los fenotipos que nuestro grupo ha descrito previamente al usar otros constructos de la misma enzima, y v) UCH-L1 promueve la internalización de la bacteria Yersinia pseudotuberculosis.

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Oculopharyngeal muscular dystrophy (OPMD) is an adult-onset disorder characterized by ptosis, dysphagia and proximal limb weakness. Autosomal-dominant OPMD is caused by a short (GCG)8–13 expansions within the first exon of the poly(A)-binding protein nuclear 1 gene (PABPN1), leading to an expanded polyalanine tract in the mutated protein. Expanded PABPN1 forms insoluble aggregates in the nuclei of skeletal muscle fibres. In order to gain insight into the different physiological processes affected in OPMD muscles, we have used a transgenic mouse model of OPMD (A17.1) and performed transcriptomic studies combined with a detailed phenotypic characterization of this model at three time points. The transcriptomic analysis revealed a massive gene deregulation in the A17.1 mice, among which we identified a significant deregulation of pathways associated with muscle atrophy. Using a mathematical model for progression, we have identified that one-third of the progressive genes were also associated with muscle atrophy. Functional and histological analysis of the skeletal muscle of this mouse model confirmed a severe and progressive muscular atrophy associated with a reduction in muscle strength. Moreover, muscle atrophy in the A17.1 mice was restricted to fast glycolytic fibres, containing a large number of intranuclear inclusions (INIs). The soleus muscle and, in particular, oxidative fibres were spared, even though they contained INIs albeit to a lesser degree. These results demonstrate a fibre-type specificity of muscle atrophy in this OPMD model. This study improves our understanding of the biological pathways modified in OPMD to identify potential biomarkers and new therapeutic targets.

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Parsimony-based phylogenetic analyses of the neotropical tribe Helieae (Gentianaceae) are presented, including 22 of the 23 genera and 60 species. This study is based on data from morphology, palynology, and seed micromorphology (127 structural characters), and DNA sequences (matK, trnL intron, ITS). Phylogenetic reconstructions based on ITS and morphology provided the greatest resolution, morphological data further helping to tentatively place several taxa for which DNA was not available (Celiantha, Lagenanthus, Rogersonanthus, Roraimaea, Senaea, Sipapoantha, Zonanthus). Celiantha, Prepusa and Senaea together appear as the sister clade to the rest of Helieae. The remainder of Helieae is largely divided into two large subclades, the Macrocarpaea subclade and the Symbolanthus subclade. The first subclade includes Macrocarpaea, sister to Chorisepalum, Tochia, and Zonanthus. Irlbachia and Neblinantha are placed as sisters to the Symbolanthus subclade, which includes Aripuana, Calolisianthus, Chelonanthus, Helia, Lagenanthus, Lehmanniella, Purdieanthus, Rogersonanthus, Roraimaea, Sipapoantha, and symbolanthus. Generic-level polyphyly is detected in Chelonanthus and Irlbachia. Evolution of morphological characters is discussed, and new pollen and seed characters are evaluated for the first time in a combined morphological-molecular phylogenetic analysis.

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Documenting the presence and abundance of the neotropical mammals is the first step for understanding their population ecology, behavior and genetic dynamics in designing conservation plans. The combination of field research with molecular genetics techniques are new tools that provide valuable biological information avoiding the disturbance in the ecosystems, trying to minimize the human impact in the process to gather biological information. The objective of this paper is to review the available non invasive sampling techniques that have been used in Neotropical mammal studies to apply to determine the presence and abundance, population structure, sex ratio, taxonomic diagnostic using mitochondrial markers, and assessing genetic variability using nuclear markers. There are a wide range of non invasive sampling techniques used to determine the species identification that inhabit an area such as searching for tracks, feces, and carcasses. Other useful equipment is the camera traps that can generate an image bank that can be valuable to assess species presence and abundance by morphology. With recent advances in molecular biology, it is now possible to use the trace amounts of DNA in feces and amplify it to analyze the species diversity in an area, and the genetic variability at intraspecific level. This is particularly helpful in cases of sympatric and cryptic species in which morphology failed to diagnose the taxonomic status of several species of brocket deer of the genus Mazama.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)