Polyphagous koinobiosis: the biology and biocontrol potential of a braconid endoparasitoid of exophytic caterpillars

Polyphagous koinobiosis might be a novel perspective to help elucidate the evolution of the physiological and ecological traits of parasitoid wasps and determine their use as biocontrol agents. The euphorine braconid Meteorus pulchricornis is a polyphagous koinobiont endoparasitoid of exophytic caterpillars from 15 families within 10 lepidopteran superfamilies. Here, the biology of this common but enigmatic parasitoid wasp is reviewed. The unique cocoon suspension system of M. pulchricornis protects it against predators during and after cocoon spinning. This structural cocoon protection method, as well as robust immune suppression mechanism, likely enables its very wide host range. In Japan, M. pulchricornis can reproduce both sexually and asexually, and the coexistence of sexual and asexual strains might be encouraged by its high polyphagy. In this review, the potential use of M. pulchricornis as a biocontrol agent is also addressed.     

Host suitability of the Mediterranean flour moth for rearing <Emphasis Type="Italic">Meteorus pulchricornis</Emphasis> (Hymenoptera: Braconidae), a polyphagous endoparasitoid of pest lepidopteran larvae

We investigated the host suitability of the Mediterranean flour moth Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) for a polyphagous koinobiont endoparasitoid Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae), a common natural enemy of various pest lepidopteran larvae. The estimated probability of adult wasp emergence was 80% or higher when eggs were laid in nearly fully grown larvae of E. kuehniella (fresh weight, >?20.0 mg). The body size of emerged adult wasps increased with the initial weight of the host larvae at oviposition. The fresh weight of adult wasps reared on E. kuehniella was approximately 60% of that when reared on a natural host Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae), and the lifetime fecundity of wasps reared on E. kuehniella was approximately half of that when reared on S. litura. Ephestia kuehniella was shown to be a positive host candidate for the mass rearing of M. pulchricornis, but further investigation is needed to increase the body size of wasps for more practical use of this species as a biocontrol agent.     

Genome-wide association analysis of host genotype and plastic wing morphological variation of an endoparasitoid wasp <Emphasis Type="Italic">Asobara japonica</Emphasis> (Hymenoptera: Braconidae)

Accumulating evidence suggests that genotype of host insects influences the development of koinobiont endoparasitoids. Although there are many potential genetic variations that lead to the internal body environmental variations of host insects, association between the host genotype and the parasitoid development has not been examined in a genome-wide manner. In the present study, we used highly inbred whole genome sequenced strains of Drosophila melanogaster to associate single nucleotide polymorphisms (SNPs) of host flies with morphological traits of Asobara japonica, a larval-pupal parasitoid wasp that infected those hosts. We quantified the outline shape of the forewings of A. japonica with two major principal components (PC1 and PC2) calculated from Fourier coefficients obtained from elliptic Fourier analysis. We also quantified wing size and estimated wasp survival. We then examined the association between the PC scores, wing size and 1,798,561 SNPs and  the association between the estimated wasp survival and 1,790,544 SNPs. As a result, we obtained 22, 24 and 14 SNPs for PC1, PC2 and wing size and four SNPs for the estimated survival with P values smaller than 10^?5. Based on the location of the SNPs, 12, 17, 11 and five protein coding genes were identified as potential candidates for PC1, PC2, wing size and the estimated survival, respectively. Based on the function of the candidate genes, it is suggested that the host genetic variation associated with the cell growth and morphogenesis may influence the wasp’s morphogenetic variation.     

Isolation and characterization of 14 microsatellite markers in <Emphasis Type="Italic">Macrodasyceras</Emphasis><Emphasis Type="Italic">hirsutum</Emphasis> (Hymenoptera: Torymidae)

Macrodasyceras hirsutum Kamijo is the seed parasitoid wasp of the bird-dispersed, dioecious tree, Ilex integra Thunb. The wasp reduces the level of dispersal mutualism between the Ilex tree and its frugivorous birds by manipulating the color of mature berries. The female trees do not blossom every year and sometimes change sex. Thus, the reproduction biology of I. integra affects the population size and structure of M. hirsutum in a forest and consequently influences the seed dispersal mutualism between the tree and birds, because of limited ability of adult locomotion. To investigate the wasp population structure with reference to the dispersal mutualism between trees and birds, we isolated 14 microsatellite loci of M. hirsutum wasps. Every locus was polymorphic among 20 females, with 3–13 alleles per locus, without linkage disequilibrium. The observed and expected heterozygosities ranged from 0.100 to 0.900 and 0.099 to 0.818, respectively, indicating their utility in molecular analyses of the wasp population.     

Identification and Characterization of MicroRNAs in Skin of Chinese Giant Salamander (<Emphasis Type="Italic">Andrias davidianus</Emphasis>) by the Deep Sequencing Approach

MicroRNAs (miRNA) play a pivotal role in regulating a broad range of biological processes, acting by cleaving mRNAs or by translational repression. However, the miRNAs from skin of Andrias davidianus have not been reported. In this study, a small-RNA cDNA library was constructed and sequenced from skin of A. davidianus. A total of 513 conserved miRNAs belonging to 174 families were identified. The remaining 108 miRNAs we identified were novel and likely to be skin tissue-specific but were expressed at low levels. The presence of randomly selected 15 miRNAs identified and their expression in eight different tissues from A. davidianus were validated by stem-loop qRT-PCR. For better understanding the functions of miRNAs, 129,791 predicated target genes were analyzed by GO and their pathways illustrated by KEGG pathway analyses. The results show that these identified miRNAs from A. davidianus skin are involved in a broad range of physiological functions including metabolism, growth, development, and immune responses. This study exhaustively identifies miRNAs and their target genes, which will ultimately pave the way for understanding their role in skin of A. davidianus and other amphibians. Further studies are necessary to better understand miRNA-mediated gene regulation.     

Genome analysis reveals insights of the endophytic <Emphasis Type="Italic">Bacillus toyonensis</Emphasis> BAC3151 as a potentially novel agent for biocontrol of plant pathogens

Diseases caused by phytopathogenic microorganisms account for enormous losses for agribusiness. Although Bacillus species are recognized as being antimicrobial producers and some may provide benefits to plants, the association between Bacillus toyonensis and plants has not been studied. In this study, the whole-genome sequenced endophytic B. toyonensis BAC3151, which has demonstrated antimicrobial activity and quorum sensing inhibition of phytopathogenic bacteria, was investigated for its potential for the production of compounds for biocontrol of plant pathogens. Four whole-genome sequenced B. toyonensis strains shared 3811 protein-coding DNA sequences (CDSs), while strain-specific CDSs, such as biosynthetic gene clusters of antimicrobials, were associated with specific chromosomal regions and mobile genetic elements of the strains. B. toyonensis strains had a higher frequency of putative bacteriocins gene clusters than that of Bacillus species traditionally used for the production of antimicrobials. In addition, gene clusters potentially involved in the production of novel bacteriocins were found in BAC3151, as well as biosynthetic genes of several other compounds, including non-ribosomal peptides, N-acyl homoserine lactonase and chitinases, revealing a genetic repertoire for antimicrobial synthesis greater than that of other Bacillus strains that have demonstrated effective activity against phytopathogens. This study showed for the first time that B. toyonensis has potential to produce various antimicrobials, and the analyses performed indicated that the endophytic strain BAC3151 can be useful for the development of new strategies to control microbial diseases in plants that are responsible for large damages in agricultural crops.     

Induction of two cyclotide-like genes <Emphasis Type="Italic">Zmcyc1</Emphasis> and <Emphasis Type="Italic">Zmcyc5</Emphasis> by abiotic and biotic stresses in <Emphasis Type="Italic">Zea mays</Emphasis>

Cyclotides are small plant disulfide-rich and cyclic proteins with a diverse range of biological activities. Cyclotide-like genes show key sequence features of cyclotides and are present in the Poaceae. In this study the cDNA of the nine cyclotide-like genes were cloned and sequenced using 3′RACE from Zea mays. The gene expression of two of these genes (Zmcyc1 and Zmcyc5) were analyzed by real-time PCR in response to biotic (Fusarium graminearum, Ustilago maydis and Rhopalosiphum maydis) and abiotic (mechanical wounding, water deficit and salinity) stresses, as well as in response to salicylic acid and methyl jasmonate elicitors to mimic biotic stresses. All isolated genes showed significant similarity to other cyclotide-like genes and were classified in two separate clusters. Both Zmcyc1 and Zmcyc5 were expressed in all studied tissues with the highest expression in leaves and lowest expression in roots. Wounding, methyl jasmonate and salicylic acid significantly induced the expression of Zmcyc1 and Zmcyc5 genes, but the higher expression was observed for Zmcyc1 as compared with Zmcyc5. Expression levels of these two genes were also induced in inoculated leaves with F. graminearum, U. maydis and also in response to insect infestation. In addition, the 1000-base-pairs (bp) upstream of the promoter of Zmcyc1 and Zmcyc5 genes were identified and analyzed using the PlantCARE database and consequently a large number of similar biotic and abiotic cis-regulatory elements were identified for these two genes.     

Range expansion and increasing impact of the introduced wasp <Emphasis Type="Italic">Aphidius</Emphasis><Emphasis Type="Italic">matricariae</Emphasis> Haliday on sub-Antarctic Marion Island

Despite the significance of biological invasions in the Antarctic region, understanding of the rates of spread and impact of introduced species is limited. Such information is necessary to develop and to justify management actions. Here we quantify rates of spread and changes in impact of the introduced wasp Aphidius matricariae Haliday, which parasitizes the invasive aphid Rhopalosiphum padi (L.), on sub-Antarctic Marion Island, to which the wasp was introduced in ca. 2001. Between 2006 and 2011, the wasp had colonised all coastal sites, with an estimated rate of spread of 3–5 km year^?1. Adult abundance doubled over the period, while impact, measured as mean percentage parasitism of R. padi, had increased from 6.9 to 30.1 %. Adult wasps have thermal tolerances (LT50s) of between ?18 and 33.8 °C, with a crystallization temperature of ?22.9 °C, and little tolerance (ca. 37 h) of low humidity at 10 °C. Desiccation intolerance is probably limiting for the adult wasps, while distribution of their aphid host likely sets ultimate distributional limits, especially towards higher elevations where R. padi is absent, despite the presence of its host grass on the island, Poa cookii (Hook. f.). Rising temperatures are benefitting P. cookii, and will probably do the same for both R. padi and A. matricariae. Our study shows that once established, spread of introduced species on the island may be rapid, emphasizing the importance of initial quarantine.     

Life history and life table of the host-feeding parasitoid <Emphasis Type="Italic">Hemiptarsenus varicornis</Emphasis> (Hymenoptera: Eulophidae)

Hemiptarsenus varicornis (Girault), a destructive host-feeding wasp, is an important biocontrol agent/larval ectoparasitoid of agromyzid leafminers worldwide. In the present study, the life history and life table of H. varicornis reared with Liriomyza trifolii (Burgess) were studied at a constant 27 °C. The developmental durations of female and male eggs, larvae, prepupae, pupae and total immature wasps were 1.00 and 1.00, 2.57 and 2.62, 0.45 and 0.37, 3.88 and 3.52, and 7.90 and 7.52 days, respectively. This wasp showed three types of host-killing behavior: reproductive parasitization (parasitism), non-reproductive host feeding (host feeding), and host stinging without oviposition or feeding (host stinging), resulting in 133.9, 303.8, and 84.2, respectively, killed host larvae. We confirm that H. varicornis is a strong synovigenic parasitoid, with an ovigeny index of 0.003. The number of host-feeding events was strongly correlated with parasitism, host-stinging events, longevity and total host mortality. The intrinsic rate of increase, the finite rate of increase, the net reproductive rate, the gross reproduction rate, and the mean length of a generation of H. varicornis were 0.3011/day, 1.3624/day, 66.22 offspring/individual, 168.33 offspring/individual, and 13.56 days, respectively. These results could contribute to a better understanding of the biocontrol efficiency of this destructive host feeder.     

Location of low copy genes in chromosomes of <Emphasis Type="Italic">Brachiaria</Emphasis> spp.

Repetitive DNA sequences have been widely used in cytogenetic analyses. The use of gene sequences with a low-copy-number, however, is little explored especially in plants. To date, the karyotype details in Brachiaria spp. are limited to the location of rDNA sites. The challenge lies in developing new probes based on incomplete sequencing data for the genus or complete sequencing of related species, since there are no model species with a sequenced genome in Brachiaria spp. The present study aimed at the physical location of conserved genes in chromosomes of Brachiaria ruziziensis, Brachiaria brizantha, and Brachiaria decumbens using RNAseq data, as well as sequences of Setaria italica and Sorghum bicolor through the fluorescent in situ hybridization technique. Five out of approximately 90 selected sequences generated clusters in the chromosomes of the species of Brachiaria studied. We identified genes in synteny with 5S and 45S rDNA sites, which contributed to the identification of chromosome pairs carrying these genes. In some cases, the species of Brachiaria evaluated had syntenic segments conserved across the chromosomes. The use of genomic sequencing data is essential for the enhancement of cytogenetic analyses.     

Regularory elements of the <Emphasis Type="Italic">copia</Emphasis> retrotransposon determine different levels of expression in different organs of males and females of <Emphasis Type="Italic">Drosophila melanogaster</Emphasis>

Using a model system in which the expression of the reporter gene lacZ is under the control of five deleted variants of the copia retrotransposon regulatory region, which includes the 5′-long terminal repeat (LTR) and the 5′-untranslated region (5′-UTR), their contribution to the control of retrotransposon activity in different organs of males and females of Drosophila melanogaster was analyzed. The whole regulatory region provides expression of the reporter gene at the embryonic stage, and in larvae and adult flies only in generative organs. The 5′-end of LTR harbors a positive regulator that determines expression of the retrotransposon in organs of all types. The 3′-end of LTR harbors a negative regulator, which is sex- and time-specific: it represses copia expression in generative organs of males at all stages of development, and only at the imaginal stage in somatic tissues, without any effect on the expression of the retrotransposon in females. 5′-UTR contains a negative regulator of copia expression: it decreases the expression in embryos and generative organs and blocks it in somatic tissues. It may be suggested that a complex set of regulatory elements was formed in the course of the evolution of the retrotransposon, which made it possible to maintain a certain level of its expression in different types of cells and tissues and at different stages of development and, thus, to limit the harm caused to the host and provide the possibility for the retrotransposon to exist in the host genome over many generations.     

Screening,tandem expression and immune activity appraisal of <Emphasis Type="Italic">Deinagkistrodon acutus</Emphasis> (pit viper) venom mimotopes from a phage display 12-mer peptide library

Objective

To design a specific polyclonal antibody against Deinagkistrodon acutus venom (DA-pAb) by immunizating New Zealand white rabbits.

Results

The IgG fraction was purified by affinity chromatography, and specific antibodies were purified by immunoaffinity chromatography. Polyclonal antibodies were subjected to ELISA and western blotting to evaluate their immune reactivity. We identified the mimotopes by screening a phage display 12-mer peptide library against D. acutus venom. After three rounds of biopanning with DA-pAb, 30 positive clones were identified. Eighteen phage clones were sequenced, and their corresponding amino acid sequences were deduced. Additional immunoassays with the peptides and DA-pAb identified five sequences as possible epitopes. Recombinant antigens synthesized with the five epitopes were used for the immunization of BALB/c mice.

Conclusion

The antibodies induced by these peptides recognized the recombinant antigen and D. acutus venom and protected mice against the hemorrhagic effects of the venom.

     

Morphoecological aspects of preimaginal stages of development of the parasitic wasp <Emphasis Type="Italic">Minotetrastichus frontalis</Emphasis> (Nees, 1834) (Insecta,Hymenoptera, Eulophidae)

This work is devoted to studying the morphology and biology of preimaginal stages of development of the parasitic wasp Minotetrastichus frontalis. The morphological characteristics of eggs and larvae, the features of interaction of the parasitic wasp with the host (Phyllonorycter issikii), and other biological characteristics were determined. For the species identification of the studied specimens of insects, we performed molecular genetic analysis using a nuclear 28S RNA gene fragment as a molecular marker. The result showed a strong genetic polymorphism of the populations of the studied species for the selected marker.     

Genetic diversity of MHC class II <Emphasis Type="Italic">DRB</Emphasis> alleles in the continental and Japanese populations of the sable <Emphasis Type="Italic">Martes zibellina</Emphasis> (Mustelidae,Carnivora, Mammalia)

The sable (Martes zibellina) is a medium-sized mustelid inhabiting forest environments in Siberia, northern China, the Korean Peninsula, and Hokkaido Island, Japan. To further understand the molecular evolution of the major histocompatibility complex (MHC), we sequenced part of exon 2 in MHC class II DRB genes, including codons encoding the antigen binding site, from 33 individuals from continental Eurasia and Japan. We identified 16 MHC class II DRB alleles (Mazi-DRBs), some of which were geographically restricted and others broadly distributed, and eight putative pseudogenes. A single-breakpoint recombination analysis detected a recombination site in the middle of exon 2. A mixed effects model of evolution analysis identified five amino acid sites presumably under positive selection. These sites were all located in the region 3′ to the recombination site, suggesting that positive selection and recombination could be committed to the diversity of the M. zibellina DRB gene. In a Bayesian phylogenetic tree, all Mazi-DRBs and the presumed pseudogenes grouped within a Mustelidae clade. The Mazi-DRBs showed trans-species polymorphism, with some alleles most closely related to alleles from other mustelid species. This result suggests that the sable DRBs have evolved under long-lasting balancing selection.     

New resources for functional analysis of omics data for the genus <Emphasis Type="Italic">Aspergillus</Emphasis>

Background

Detailed and comprehensive genome annotation can be considered a prerequisite for effective analysis and interpretation of omics data. As such, Gene Ontology (GO) annotation has become a well accepted framework for functional annotation. The genus Aspergillus comprises fungal species that are important model organisms, plant and human pathogens as well as industrial workhorses. However, GO annotation based on both computational predictions and extended manual curation has so far only been available for one of its species, namely A. nidulans.

Results

Based on protein homology, we mapped 97% of the 3,498 GO annotated A. nidulans genes to at least one of seven other Aspergillus species: A. niger, A. fumigatus, A. flavus, A. clavatus, A. terreus, A. oryzae and Neosartorya fischeri. GO annotation files compatible with diverse publicly available tools have been generated and deposited online. To further improve their accessibility, we developed a web application for GO enrichment analysis named FetGOat and integrated GO annotations for all Aspergillus species with public genome sequences. Both the annotation files and the web application FetGOat are accessible via the Broad Institute's website (http://www.broadinstitute.org/fetgoat/index.html). To demonstrate the value of those new resources for functional analysis of omics data for the genus Aspergillus, we performed two case studies analyzing microarray data recently published for A. nidulans, A. niger and A. oryzae.

Conclusions

We mapped A. nidulans GO annotation to seven other Aspergilli. By depositing the newly mapped GO annotation online as well as integrating it into the web tool FetGOat, we provide new, valuable and easily accessible resources for omics data analysis and interpretation for the genus Aspergillus. Furthermore, we have given a general example of how a well annotated genome can help improving GO annotation of related species to subsequently facilitate the interpretation of omics data.

     

A homomeric geranyl diphosphate synthase-encoding gene from <Emphasis Type="Italic">Camptotheca acuminata</Emphasis> and its combinatorial optimization for production of geraniol in <Emphasis Type="Italic">Escherichia coli</Emphasis>

Geranyl diphosphate (GPP), the unique precursor for all monoterpenoids, is biosynthesized from isopentenyl diphosphate and dimethylallyl diphosphate via the head-to-tail condensation reaction catalyzed by GPP synthase (GPPS). Herein a homomeric GPPS from Camptotheca acuminata, a camptothecin-producing plant, was obtained from 5′- and 3′-rapid amplification of cDNA ends and subsequent overlap extension and convenient PCR amplifications. The truncate CaGPPS was introduced to replace ispA of pBbA5c-MevT(CO)-MBIS(CO, ispA), a de novo biosynthetic construct for farnesyl diphosphate generation, and overexpressed in Escherichia coli, together with the truncate geraniol synthase-encoding gene from C. acuminata (tCaGES), to confirm CaGPPS-catalyzed reaction in vivo. A 24.0 ± 1.3 mg L^?1 of geraniol was produced in the recombinant E. coli. The production of GPP was also validated by the direct UPLC-HRMS^E analyses. The tCaGPPS and tCaGES genes with different copy numbers were introduced into E. coli to balance their catalytic potential for high-yield geraniol production. A 1.6-fold increase of geraniol production was obtained when four copies of tCaGPPS and one copy of tCaGES were introduced into E. coli. The following fermentation conditions optimization, including removal of organic layers and addition of new n-decane, led to a 74.6 ± 6.5 mg L^?1 of geraniol production. The present study suggested that the gene copy number optimization, i.e., the ratio of tCaGPPS and tCaGES, plays an important role in geraniol production in the recombinant E. coli. The removal and addition of organic solvent are very useful for sustainable high-yield production of geraniol in the recombinant E. coli in view of that the solubility of geraniol is limited in the fermentation broth and/or n-decane.     

Protective Effect of the Sulfated Agaran Isolated from the Red Seaweed <Emphasis Type="Italic">Laurencia aldingensis</Emphasis> Against Toxic Effects of the Venom of the Snake, <Emphasis Type="Italic">Lachesis muta</Emphasis>

Snakebite is a serious occupational hazard affecting mainly rural populations of tropical and subtropical developing countries. Lachesis muta (Bushmaster) bites are extremely serious but are rarely reported in the literature. Bushmaster envenomings are characterized by intense local pain, edema, neurotoxicity, hypotension, local hemorrhage, and dramatic systemic alterations. Antivenom treatment has regularly been used for more than a century; however, it fails to neutralize local tissue damage and hemorrhage, leading to morbidity or disabilities in victims. Thus, the production and clinical use of antivenom must be improved. The present work characterizes, for the first time, a sulfated polysaccharide from the red seaweed, Laurencia aldingensis, including its neutralizing effect on some toxic activities of L. muta venom. Chemical and spectroscopic analyses showed that L. aldingensis produces sulfated agarans with the A-units partially C-2 sulfated or 6-O-methoxylated presetting the B-units in the cyclized (3,6-anhydro-α-L-galactose) or in the non-cyclized form (α-L-galactose). The latter is significantly substituted by sulfate groups on C-6. In vitro and in vivo assays showed that this sulfated agaran inhibited hemolysis, coagulation, proteolysis, edema, and hemorrhage of L. muta venom. Neutralization of hemorrhagic activity was also observed when the agaran was administered by different routes and after or before the venom injection. Furthermore, the agaran blocked the edema caused by a phospholipase A₂ isolated from the L. muta venom. Experimental evidence therefore indicates that the sulfated agaran of L. aldingensis has potential to aid antivenom therapy of accidents caused by L. muta venom and may help to develop more effective antivenom treatments of snake bites in general.     

Evaluation of the physiological activity of venom from the Eurasian water shrew <Emphasis Type="Italic">Neomys fodiens</Emphasis>

Background

Animal toxins can have medical and therapeutic applications. Principally, toxins produced by insects, arachnids, snakes and frogs have been characterized. Venomous mammals are rare, and their venoms have not been comprehensively investigated. Among shrews, only the venom of Blarina brevicauda has been analysed so far, and blarina toxin has been proven to be its main toxic component. It is assumed that Neomys fodiens employs its venom to hunt larger prey. However, the toxic profile, properties and mode of action of its venom are largely unknown. Therefore, we analysed the cardio-, myo- and neurotropic properties of N. fodiens venom and saliva of non-venomous Sorex araneus (control tests) in vitro in physiological bioassays carried out on two model organisms: beetles and frogs. For the first time, we fractionated N. fodiens venom and S. araneus saliva by performing chromatographic separation. Next, the properties of selected compounds were analysed in cardiotropic bioassays in the Tenebrio molitor heart.

Results

The venom of N. fodiens caused a high decrease in the conduction velocity of the frog sciatic nerve, as well as a significant decrease in the force of frog calf muscle contraction. We also recorded a significant decrease in the frog heart contractile activity. Most of the selected compounds from N. fodiens venom displayed a positive chronotropic effect on the beetle heart. However, one fraction caused a strong decrease in the T. molitor heart contractile activity coupled with a reversible cardiac arrest. We did not observe any responses of the insect heart and frog organs to the saliva of S. araneus. Preliminary mass spectrometry analysis revealed that calmodulin-like protein, thymosin β-10, hyaluronidase, lysozyme C and phospholipase A2 are present in the venom of N. fodiens, whereas thymosin β4, lysozyme C and β-defensin are present in S. araneus saliva.

Conclusion

Our results showed that N. fodiens venom has stronger paralytic properties and lower cardioinhibitory activity. Therefore, it is highly probable that N. fodiens might use its venom as a prey immobilizing agent. We also confirmed that S. araneus is not a venomous mammal because its saliva did not exhibit any toxic effects.

     

The complete chloroplast genome of the green algae <Emphasis Type="Italic">Hariotina reticulata</Emphasis> (Scenedesmaceae,Sphaeropleales, Chlorophyta)

In this study, the chloroplast genome of Hariotina reticulata was fully sequenced and compared to other Sphaeropleales chloroplast genomes. It is 210,757 bp larger than most Sphaeropleales cpDNAs. It presents a traditional chloroplast structure, and contains 103 genes, including 68 protein-coding genes, six rRNA genes and 29 tRNA genes. The coding region constitutes of 43% of the whole cpDNA. Eighteen introns are found in 11 genes and six introns are unique for Hariotina. 11 open reading frames are identified among these introns. The synteny between Hariotina and Acutodesmus cpDNAs is in general identical, while within Sphaeropleales order, high variability in cpDNA architecture is indicated by general high DCJ distances. Ankyra judayi exhibits the greatest dissimilarity in gene synteny to the others and share some unique gene clusters with Treubaria triappendiculata. The phylogenomic analyses show that A. judayi is clustered with Treubariaceae species and sister to Chlorophyceae incertae sedis and other Sphaeropleales species. The monophyly of Sphaeropleales is rejected.