甲壳动物精氨酸激酶的结构与功能

精氨酸激酶（Arginine kinase）是调节无脊椎动物能量代谢的重要酶,在调节无脊椎动物体内磷酸精氨酸与ATP之间的能量平衡过程中具有重要作用。甲壳动物是节肢动物门内最重要的类群之一,并具有重要的经济价值。本文综述了甲壳动物体内精氨酸激酶的分子构象、表达变化及生理功能等方面的研究进展,为深入研究甲壳动物的能量代谢调控机制提供必要的参考。另外,文中对甲壳动物精氨酸激酶的重要性和研究中存在的问题进行了讨论。     

软体动物和甲壳动物酚氧化酶的研究进展

软体动物和甲壳动物的很多品种都是重要的经济养殖品种.随着养殖业集约化程度的提高,各种病害频繁发生,造成了巨大的经济损失.于是越来越多的人开始关注软体动物和甲壳动物的免疫防御系统,并对其进行研究.酚氧化酶(phenoloxidase,PO)是一种含铜的氧化酶,广泛存在于微生物、动物和植物体内.作为酚氧化酶原激活系统的重要一员,PO在无脊椎动物的先天免疫机制中起着重要的作用,有关其生物化学、免疫学和分子生物学特性的研究一直以来受到广泛关注,尤其在节肢动物中进展很快.作者对酚氧化酶在软体和甲壳动物中的功能、组织定位及表达、基因克隆和序列分析及其系统演化等几个方面的研究进展进行了综述.基因序列分析和系统进化树证据均表明,催化功能相同的软体动物酪氨酸酶与节肢动物PO的基因有较大差异.该结果对目前被广泛接受并使用的酪氨酸酶专门用于哺乳类,酚氧化酶专门用于无脊椎动物的分类法提出了挑战.因此作者建议,将酚氧化酶专门用于节肢动物,酪氨酸酶用于软体动物等非节肢动物和脊椎动物.     

节肢动物血蓝蛋白家族的组成与演化

血蓝蛋白是动物界的三类呼吸功能蛋白之一,目前仅发现于节肢动物和软体动物等少数动物类群中。不同亚型的血蓝蛋白有不同的理化性质和序列,但均结合氧分子,并以六聚体,甚至更复杂的聚合体结构存在。血蓝蛋白与酚氧化酶、拟血蓝蛋白、昆虫储存蛋白以及昆虫储存蛋白受体等结构类似、进化上近缘的分子共同组成了血蓝蛋白超家族。该文主要介绍了血蓝蛋白家族成员在节肢动物四大类群（螯肢动物、多足动物、甲壳动物和六足动物）中已知的分布、结构和功能,并重点综述了血蓝蛋白家族成员在节肢动物系统演化研究中发挥的独特而有效的作用,进一步强调了在更多节肢动物类群中研究血蓝蛋白家族的功能和演化的重要性。     

节肢动物的分类和演化

节肢动物门是动物界中最大的1个门。按新的分类系统,本门分三叶虫亚门(已灭绝)、螯肢亚门、甲壳亚门、六足亚门和多足亚门等5亚门。六足亚门相当于以前分类系统中的昆虫纲(广义的), 是最重要的一类节肢动物;此亚门分原尾纲、弹尾纲、双尾纲和昆虫纲(狭义的)等4纲;昆虫纲分3亚纲30目,包括了前昆虫纲“有翅亚纲”中的各目。为便于读者了解新、旧系统的异同,文中列举前人的代表性系统加以对照。同时,对学术界关于节肢动物的起源和演化的一些新观点予以必要的说明,对现时流行的“泛节肢动物”、“泛甲壳动物”等概念作了简要的介绍。     

节肢动物线粒体基因组与系统发生重建

对mt基因组的比较研究是探讨节肢动物系统发生的有效手段之一。基因的排列和DNA序列可以为重建节肢动物的系统发生提供有用的信息。目前,已测定mt基因组全序列的节肢动物已增加到44种。归纳、总结了节肢动物mt基因组的基本特征、基因顺序、基因重排的发生和机制等。简要评述基于mt基因组的节肢动物系统发生研究。     

节肢动物线粒体基因组研究进展与基因顺序分析

在总结了68种节肢动物线粒体基因组的测序种类、基因组组成、结构及基因排序情况的基础上,特别对节肢动物线粒体基因组基因排列顺序数据进行了详细的分析。线粒体基因组基因排列顺序数据显示六足动物与甲壳动物之间相似,螯肢动物与多足动物相似,这个结果和以前Boore(1998)对节肢动物线粒体基因组顺序分析结果不同,却和核rRNA数据的分析结果一致。     

大兴安岭重度火烧迹地地表土壤节肢动物群落特征

火是生态系统的主要干扰因子之一,直接影响地表土壤动物群落多样性。为了解大兴安岭火烧迹地地表土壤动物群落恢复状况,于2016年6月和8月,选取松岭区南瓮河国家级自然保护区内2006年落叶松白桦混交林重度火烧迹地为实验样地、未受干扰的混交林为对照样地,采用陷阱法研究地表土壤节肢动物群落组成与多样性。本研究共捕获地表土壤节肢动物17 460只,隶属5纲14目57科85属。其中大型土壤节肢动物隶属4纲11目36科55属,优势类群为铺道蚁属（Tetramorium）;中小型土壤节肢动物隶属2纲3目18科30属,优势类群为球角跳属（Hypogastrura）。整体而言,重度火烧迹地地表土壤节肢动物总个体数多于对照样地,而总类群数低于对照样地,但仅大型地表土壤节肢动物个体数明显低于对照样地（P < 0.05）。研究时段,8月份中小型土壤节肢动物的个体数明显高于6月份（P < 0.05）。群落多样性分析表明,重度火烧迹地与对照样地的地表土壤节肢动物群落多样性指数差异性不显著（P > 0.05）,其中6月份中小型地表土壤节肢动物Shannon-Wiener指数、Pielou均匀度指数与Margalef丰富度指数明显低于8月份（P < 0.01）,而6月份Simpson优势度指数高于8月份（P < 0.01）。火烧迹地与对照样地土壤节肢动物群落相似性系数为0.78,不同月份之间地表土壤节肢动物群落相似性均为0.43,表明地表土壤节肢动物群落总体变化较小,但地表土壤节肢动物群落随时间发生改变。地表土壤节肢动物对研究区域资源的利用存在明显的差异（P < 0.01）,重度火烧迹地可共同利用资源增多,对照样地可共同利用资源少而优势现象明显。重度火烧迹地地表主要土壤动物类群因可利用资源增加而导致生态位重叠指数增加。典型判别分析显示,地表土壤节肢动物群落受火烧干扰影响,且存在明显的季节变化。     

保幼激素生物合成研究进展

保幼激素（juvenile hormone,JH）是存在于昆虫、甲壳动物和部分植物体内的倍半萜类衍生物。在昆虫和甲壳动物体内,保幼激素主要调节变态和生殖活动。在植物体内,则可能作为异株克生物质发挥作用。保幼激素主要通过细胞质内的甲羟戊酸途径（MVA）合成,植物质体内存在萜类合成的1-去氧木糖-5-磷酸途径（DXP）。MVA和DXP途径通过单向质子协同运输系统进行协调,使DXP途径中形成的前体化合物参与MVA途径的倍半萜合成。JH生物合成的主要步骤己基本查明,但与合成相关的酶学研究还较薄弱。生物合成酶的分子生物学是近来研究的热点,相关酶的cDNA克隆已有报道。JH生物合成酶的进一步研究有助于查明JH生物合成调控机制,深化对节肢动物生殖的理解,还可为新型杀虫剂开发提供可能的靶标。     

高等甲壳动物性别决定机制及其性逆转

高等甲壳动物性别决定机制及其性逆转康现江王所安（河北大学生物系保定０７１００２）关键词高等甲壳动物性别决定性逆转在我国,十足目甲壳动物（尤其是对虾属的种类）的养殖创造了显著的经济效益和社会效益。如何在现有的基础上提高其效益？途径之一即进行遗传育种的研...     

蜱类卵黄发生及激素对其生殖的调控

蜱类属节肢动物门、蛛形纲、蜱螨亚纲,是专营吸血的体外寄生虫,对人畜造成极大的危害,同时也是一些重要疾病的传播媒介,还能储存宿主[1]。研究激素对蜱类卵黄发生及激素对其生殖的调控有着十分重要的意义。1蜱的卵黄发生Balashov[2]将节肢动物卵的成熟分为5个时期,即卵黄发生前期（revltellogemcstage;包括Ⅰ,Ⅱ期）,卵黄发生期（vitellogenicstage;Ⅲ期）,排卵前期（Preovulatestage;Ⅳ期）和排卵期（ovulatestage;V期）而卖和等l’］,EngClmannl‘］和HagCdom等l’］将其归为3个时期：卵黄发生前期、卵黄发生期、卵黄发生…     

Of mites and millipedes: Recent progress in resolving the base of the arthropod tree

Deep‐level arthropod phylogeny has been in a state of upheaval ever since the emergence of molecular tree reconstruction approaches. While a consensus has settled in that hexapods are more closely related to crustaceans than to myriapods, the phylogenetic position of the latter has remained a matter of debate. Mitochondrial, nuclear, and genome‐scale studies have proposed rejecting the long‐standing superclade Mandibulata, which unites myriapods with insects and crustaceans, in favor of a clade that unites myriapods with chelicerates and has become known as Paradoxapoda or Myriochelata. Here we discuss the progress, problems, and prospects of arriving at the final arthropod tree.     

Arthropod communities on hybrid and parental cottonwoods are phylogenetically structured by tree type: Implications for conservation of biodiversity in plant hybrid zones

Although hybridization in plants has been recognized as an important pathway in plant speciation, it may also affect the ecology and evolution of associated communities. Cottonwood species (Populus angustifolia and P. fremontii) and their naturally occurring hybrids are known to support different plant, animal, and microbial communities, but no studies have examined community structure within the context of phylogenetic history. Using a community composed of 199 arthropod species, we tested for differences in arthropod phylogenetic patterns within and among hybrid and parental tree types in a common garden. Three major patterns emerged. (1) Phylogenetic diversity (PD) was significantly different between arthropod communities on hybrids and Fremont cottonwood when pooled by tree type. (2) Mean phylogenetic distance (MPD) and net relatedness index (NRI) indicated that communities on hybrid trees were significantly more phylogenetically overdispersed than communities on either parental tree type. (3) Community distance (D_pw) indicated that communities on hybrids were significantly different than parental species. Our results show that arthropod communities on parental and hybrid cottonwoods exhibit significantly different patterns of phylogenetic structure. This suggests that arthropod community assembly is driven, in part, by plant–arthropod interactions at the level of cottonwood tree type. We discuss potential hypotheses to explain the effect of plant genetic dissimilarity on arthropod phylogenetic community structure, including the role of competition and environmental filtering. Our findings suggest that cottonwood species and their hybrids function as evolutionarily significant units (ESUs) that affect the assembly and composition of associated arthropod communities and deserve high priority for conservation.     

Trees as templates for tropical litter arthropod diversity

Increased tree species diversity in the tropics is associated with even greater herbivore diversity, but few tests of tree effects on litter arthropod diversity exist. We studied whether tree species influence patchiness in diversity and abundance of three common soil arthropod taxa (ants, gamasid mites, and oribatid mites) in a Panama forest. The tree specialization hypothesis proposes that tree-driven habitat heterogeneity maintains litter arthropod diversity. We tested whether tree species differed in resource quality and quantity of their leaf litter and whether more heterogeneous litter supports more arthropod species. Alternatively, the abundance–extinction hypothesis states that arthropod diversity increases with arthropod abundance, which in turn tracks resource quantity (e.g., litter depth). We found little support for the hypothesis that tropical trees are templates for litter arthropod diversity. Ten tree species differed in litter depth, chemistry, and structural variability. However, the extent of specialization of invertebrates on particular tree taxa was low and the more heterogeneous litter between trees failed to support higher arthropod diversity. Furthermore, arthropod diversity did not track abundance or litter depth. The lack of association between tree species and litter arthropods suggests that factors other than tree species diversity may better explain the high arthropod diversity in tropical forests.     

Eubacterial phylogeny based on translational apparatus proteins.

Lateral gene transfers are frequent among prokaryotes, although their detection remains difficult. If all genes are equally affected, this questions the very existence of an organismal phylogeny. The complexity hypothesis postulates the existence of a core of genes (those involved in numerous interactions) that are unaffected by transfers. To test the hypothesis, we studied all the proteins involved in translation from 45 eubacterial taxa, and developed a new phylogenetic method to detect transfers. Few of the genes studied show evidence for transfer. The phylogeny based on the genes devoid of transfer is very consistent with the ribosomal RNA tree, suggesting that an eubacterial phylogeny does exist.     

Molecular phylogenetic analysis of Commiphora (Burseraceae) yields insight on the evolution and historical biogeography of an "impossible" genus

Expansion of the arid zone of sub-Saharan tropical Africa during the Miocene is posited as a significant contributing factor in the evolution of contemporary African flora. Nevertheless, few molecular phylogenetic studies have tested this hypothesis using reconstructed historical biogeographies of plants within this zone. Here, we present a molecular phylogeny of Commiphora, a predominantly tropical African, arid-adapted tree genus, in order to test the monophyly of its taxonomic sections and identify clades that will help direct future study of this species-rich and geographically widespread taxon. We then use multiple fossil calibrations of Commiphora phylogeny to determine the timing of well-supported diversification events within the genus and interpret these age estimates to determine the relative contribution of vicariance and dispersal in the expansion of Commiphora's geographic range. We find that Commiphora is sister to Vietnamese Bursera tonkinensis and that its crown group radiation corresponds with the onset of the Miocene.     

Molecular phylogenies of Parabasalia inferred from four protein genes and comparison with rRNA trees

The molecular phylogeny of parabasalids has mainly been inferred from small subunit (SSU) rRNA sequences and has conflicted substantially with systematics based on morphological and ultrastructural characters. This raises the important question, how congruent are protein and SSU rRNA trees? New sequences from seven diverse parabasalids (six trichomonads and one hypermastigid) were added to data sets of glyceraldehyde-3-phosphate dehydrogenase (GAPDH), enolase, alpha-tubulin and beta-tubulin and used to construct phylogenetic trees. The GAPDH tree was well resolved and identical in topology to the SSU rRNA tree. This both validates the rRNA tree and suggests that GAPDH should be a valuable tool in further phylogenetic studies of parabasalids. In particular, the GAPDH tree confirmed the polyphyly of Monocercomonadidae and Trichomonadidae and the basal position of Trichonympha agilis among parabasalids. Moreover, GAPDH strengthened the hypothesis of secondary loss of cytoskeletal structures in Monocercomonadidae such as Monocercomonas and Hypotrichomonas. In contrast to GAPDH, the enolase and both tubulin trees are poorly resolved and rather uninformative about parabasalian phylogeny, although two of these trees also identify T. agilis as representing the basal-most lineage of parabasalids. Although all four protein genes show multiple gene duplications (for 3-6 of the seven taxa examined), most duplications appear to be relatively recent (i.e., species-specific) and not a problem for phylogeny reconstruction. Only for enolase are there more ancient duplications that may confound phylogenetic interpretation.     

Mitochondrial DNA,morphology, and the phylogenetic relationships of Antarctic icefishes (Notothenioidei: Channichthyidae)

The Channichthyidae is a lineage of 16 species in the Notothenioidei, a clade of fishes that dominate Antarctic near-shore marine ecosystems with respect to both diversity and biomass. Among four published studies investigating channichthyid phylogeny, no two have produced the same tree topology, and no published study has investigated the degree of phylogenetic incongruence between existing molecular and morphological datasets. In this investigation we present an analysis of channichthyid phylogeny using complete gene sequences from two mitochondrial genes (ND2 and 16S) sampled from all recognized species in the clade. In addition, we have scored all 58 unique morphological characters used in three previous analyses of channichthyid phylogenetic relationships. Data partitions were analyzed separately to assess the amount of phylogenetic resolution provided by each dataset, and phylogenetic incongruence among data partitions was investigated using incongruence length difference (ILD) tests. We utilized a parsimony-based version of the Shimodaira-Hasegawa test to determine if alternative tree topologies are significantly different from trees resulting from maximum parsimony analysis of the combined partition dataset. Our results demonstrate that the greatest phylogenetic resolution is achieved when all molecular and morphological data partitions are combined into a single maximum parsimony analysis. Also, marginal to insignificant incongruence was detected among data partitions using the ILD. Maximum parsimony analysis of all data partitions combined results in a single tree, and is a unique hypothesis of phylogenetic relationships in the Channichthyidae. In particular, this hypothesis resolves the phylogenetic relationships of at least two species (Channichthys rhinoceratus and Chaenocephalus aceratus), for which there was no consensus among the previous phylogenetic hypotheses. The combined data partition dataset provides substantial statistical power to discriminate among alternative hypotheses of channichthyid relationships. These findings suggest the optimal strategy for investigating the phylogenetic relationships of channichthyids is one that uses all available phylogenetic data in analyses of combined data partitions.     

Phylogeny of firs (genus <Emphasis Type="Italic">Abies</Emphasis>, Pinaceae) based on multilocus nuclear markers (AFLP)

To study the phylogenetic relationships, evolutionary history, and molecular systematics of firs (genus Abies), the phylogenetic reconstruction, based on nuclear multilocus markers—amplified fragment length polymorphism (AFLP)—was conducted. Using seven combinations of selective primers, 84 samples of 39 taxa were genotyped for 553 polymorphic AFLP loci. A comparison with our earlier chloroplast and mitochondrial phylogenies of the genus (in 2014) shows that the nuclear phylogeny generally is more congruent to the chloroplast tree. Most of the clades resolved by the chloroplast phylogeny were supported also in the AFLP tree. Employing the nuclear DNA-based tree, we revealed the presence of new groups and the differences in the topology of several clades. AFLP confirmed the monophyly of Asian species of section Balsamea and their sister position in relation to the American group of species of this section. As shown by the tree of chloroplast DNA, Asian species of section Balsamea do not form a monophyletic group, but belong to the clade comprising the majority of Asian species. Phylogenetically mitochondrial DNA data to a large extent are not congruent to the nuclear and chloroplast DNA trees, and are more in line with geographical distribution of species. Conflicts between nuclear and cytoplasmic phylogeny were analyzed. Taking them into account, we consider the hypothesis of a hybrid origin of particular groups of firs, including ancient hybridization in section Balsamea. A comparison of molecular data with traditional taxonomy of the genus is discussed.     

Species trees for the tree swallows (Genus Tachycineta): An alternative phylogenetic hypothesis to the mitochondrial gene tree

The New World swallow genus Tachycineta comprises nine species that collectively have a wide geographic distribution and remarkable variation both within- and among-species in ecologically important traits. Existing phylogenetic hypotheses for Tachycineta are based on mitochondrial DNA sequences, thus they provide estimates of a single gene tree. In this study we sequenced multiple individuals from each species at 16 nuclear intron loci. We used gene concatenated approaches (Bayesian and maximum likelihood) as well as coalescent-based species tree inference to reconstruct phylogenetic relationships of the genus. We examined the concordance and conflict between the nuclear and mitochondrial trees and between concatenated and coalescent-based inferences. Our results provide an alternative phylogenetic hypothesis to the existing mitochondrial DNA estimate of phylogeny. This new hypothesis provides a more accurate framework in which to explore trait evolution and examine the evolution of the mitochondrial genome in this group.