Nanos functions to maintain the fate of the small micromere lineage in the sea urchin embryo

The translational regulator nanos is required for the survival and maintenance of primordial germ cells during embryogenesis. Three nanos homologs are present in the genome of the sea urchin Strongylocentrotus purpuratus, all of which are expressed with different timing in the small micromere lineage. This lineage is set-aside during embryogenesis and contributes to constructing the adult rudiment. Small micromeres lacking Sp-nanos1 and Sp-nanos2 undergo an extra division and are not incorporated into the coelomic pouches. Further, these cells do not accumulate Vasa protein even though they retain vasa mRNA. Larvae that develop from Sp-nanos1 and 2 knockdown embryos initially appear normal, but do not develop adult rudiments; although they are capable of eating, over time they fail to grow and eventually die. We conclude that the acquisition and maintenance of multipotency in the small micromere lineage requires nanos, which may function in part by repressing the cell cycle and regulating other multipotency factors such as vasa. This work, in combination with other recent results in Ilyanassa and Platynereis dumerilii, suggests the presence of a conserved molecular program underlying both primordial germ cell and multipotent cell specification and maintenance.     

Plant-parasitic Nematode Problems in the Pacific Islands

The Pacific islands have a diverse range of food and cash crops with indigenous and introduced nematode problems. The staple food crops have serious nematode pests, such as Meloidogyne spp. on sweet potato, Hirschmanniella miticausa causing corm rot of taro, and Pratylenchus coffeae and Radopholus sp. producing tuber dry rot of yams. Bananas are infested with P. coffeae or R. similis, citrus with Tylenchulus semipenetrans, rice with Aphelenchoides besseyi, and ginger with Meloidogyne spp. and R. similis. Rotylenchulus reniformis, P. zeae, P. brachyurus, and Helicotylenchus spp. are important on all of these and other crops, such as sugarcane, passion fruit, pawpaw, and cassava. Meloidogyne spp. cause serious damage to local and introduced leaf and fruit vegetables and other crops, such as tobacco, sugarcane, pawpaw, black pepper, and pyrethrum. Many other plant-parasitic genera and species, some undescribed, occur in the Pacific, and there are many islands still to be investigated.     

On the occurrence of the fireworm Eurythoe?complanata complex (Annelida,Amphinomidae) in the Mediterranean Sea with an updated revision of the alien Mediterranean amphinomids

The presence of two species within the Eurythoe complanata complex in the Mediterranean Sea is reported, as well as their geographical distributions. One species, Eurythoe laevisetis, occurs in the eastern and central Mediterranean, likely constituting the first historical introduction to the Mediterranean Sea and the other, Eurythoe complanata, in both eastern and Levantine basins. Brief notes on their taxonomy are also provided and their potential pathways for introduction to the Mediterranean are discussed. A simplified key to the Mediterranean amphinomid genera and species of Eurythoe and Linopherus is presented plus an updated revision of the alien amphinomid species reported previously from the Mediterranean Sea. A total of five exotic species have been included; information on their location, habitat, date of introduction and other relevant features is also provided.     

Sequencing and complementation analysis of the nifUSV genes from Azospirillum brasilense

The functionality of nitrogenase in diazotrophic bacteria is dependent upon nif genes other than the structural nifH, D, and K genes which encode the enzyme subunit proteins. Such genes are involved in the activation of nif gene expression, maturation of subunit proteins, cofactor biosynthesis, and electron transport. In this work, approximately 5500 base pairs located within the major nif gene cluster of Azospirillum brasilense Sp7 have been sequenced. The deduced open reading frames were compared to the nif gene products of Azotobacter vinelandii and other diazotrophs. This analysis indicates the presence of five ORFs encoding ORF2, nifU, nifS, nifV, and ORF4 in the same sequential organization as found in other organisms. Consensus σ⁵⁴ and NifA binding sites are present in the putative promoter region upstream of ORF2 in the A. brasilense sequence. The nifV gene of A. brasilense but not nifU or nifS complemented corresponding mutants strains of A. vinelandii.     

Studies on the arrangement patterns of nucleocapsids within the envelopes of nuclear-polyhedrosis virus in the fat-body cells of the brown tail moth, Euproctis similis

Occluded viruses of the Entomopoxvirus (D)/¹:¹/¹:X/X:I/O ( = Vagoiavirus) group have been found in Othnonius batesi (Scarabaeidae: Melolonthinae), Dermolepida albohirtum (Scarabaeidae: Melolonthinae), and Aphodius tasmaniae (Scarabaeidae:Aphodiinae). Diagnostic criteria are given for the virus infections in the respective native host larvae based upon both macroscopic and microscopical observations where possible. The distinguishing characteristics of the virus spheroids and spindles from the three host species are compared with each other and with similar bodies present in other entomopoxvirus infections. Virus-containing spheroids of the O. batesi and D. albohirtum viruses were barely infective at dosages fed to native host larvae in the laboratory, and the disease course of each was prolonged. Cross-infection feeding trials of the D. albohirtum virus in several other melolonthine species larvae were negative.     

Genetics of the St Serotype System in TETRAHYMENA PYRIFORMIS, Syngen 1

Genetic analyses using lines of Tetrahymena pyroformis manifesting different serotypes indicate that the St serotypes are governed by alleles at a single genetic locus. These alleles are termed St^A and St^C. The St locus is not closely linked to any of the other well-studied loci examined. Differentiation in St^A/St^C heterozygotes follows a pattern very similar to that observed with lines heterozygous at the other loci. Initially both alleles are expressed, but as the synclone divides, lines develop that manifest one allele or the other but not both. The time of differentiation is very early in the clonal life cycle, and the output ratio is eccentric. The pattern of development of the St locus places it in a category with the mating type and H serotype loci.     

Specificity of the Antheridogen from Ceratopteris thalictroides (L.) Brongn

Characteristics of the fern antheridogen from Ceratopteris thalictroides (L.) Brongn. are investigated. These are: (a) determination of molecular size (it is readily dialyzable), (b) pK_a (about 5), (c) movement in thin layer chromatography, and (d) ability to induce dark germination of fern spores. These four characteristics are compared to the same characteristics of three other antheridogens (antheridogens A and B or GA). Molecular size and pK_a are similar, but, the antheridogens are separable from each other using thin layer chromatography. It was also shown that spore germination is not induced by the Ceratopteris antheridogen, even in its own spores, a characteristic not reported as shared by the other antheridogens. However, the inconsistency of spore germination as an assay for antheridogen is demonstrated. The presence of gametophyte-produced allelopathic substances is also shown.     

Review and revision of the West Timor Permian Graphiocrinus species of Johannes Wanner

In a series of papers published between 1916 and 1949 Johannes Wanner assigned or reassigned more than 1700 crinoid specimens to 26 species or subspecies of Graphiocrinus. Nine of the 26 species were subsequently transfered to other cladid genera by Wanner or other authors. Study of the amalgamated Netherlands collections of the West Timor crinoids in Naturalis Biodiversity Center in Leiden, resulted in recognition that few of the West Timor Graphiocrinus species unquestionably belonged to the genus. Review of these species and subspecies resulted in reassignment of 12 species to other genera, whereas other species and individual specimens are considered indeterminate members of several families because they lack the arms preventing positive generic identifications. This study also resulted in significant revision of the Erisocrinoidea.New taxa introduced are: Graphiocrinoidea n. superfam., Rautscholdticrinus n. gen., and Ekmelocrinus n. gen. Reassigned taxa are: Rautscholdticrinus indicus (Wanner, 1916) n. comb.; Rautscholdticrinus weidnerii (Wanner, 1937) n. comb.; Graffhamicrinus? crassus (Wanner, 1924) n. comb.; Neocatacrinus? depressus (Wanner, 1916) n. comb.; Ekmelocrinus amplior (Wanner, 1924) n. comb.; Ekmelocrinus subamplior (Wanner, 1949) n. comb.; Ekmelocrinus ovoides (Wanner, 1949) n. comb.; Ekmelocrinus verbeeki (Wanner, 1916) n. comb.; Ekmelocrinus vermistriatus (Wanner, 1916) n. comb., nomen correctum; Permiocrinus pumilus (Wanner, 1916) n. comb.; Permiocrinus quinquelobus (Wanner, 1916) n. comb.; and Apographiocrinus? rugosus (Wanner, 1916) n. comb.     

The taxonomic significance of the fatty acid content of seeds of Linum

About sixty taxa in the genusLinum are arranged systematically and are compared using data published earlier for the fatty acid content of their seeds. Plants of sect.Linum, of sect.Dasylinum, and Old World species of sect.Linastrum generally have higher percentages of linolenic acid and lower percentages of linoleic acid; plants of sect.Syllinum, of sect.Cathartolinum, and New World species of sect.Linastrum have the reverse tendencies. The segregation ofL. stelleroides from other species of sect.Linum and the maintenance ofL. tenuifolium in a section separate from other tested species are supported.     

Diversity of the Schizophoria lineage (Brachiopoda: Orthida) in the Lower and Middle Devonian of Poland and adjacent areas

The nominative subgenus of Schizophoria (Brachiopoda, Orthida) is represented in the Lower and Middle Devonian of Poland and of the western Ukraine by six taxa: late Emsian Schizophoria (S.) interstrialis, late Eifelian S. (S.) schnuri biscissa, early Givetian S. (S.) schnuri schnuri, middle to late Givetian S. (S.) schnuri prohibita ssp.n., middle Givetian S. (S.) parvaepunctata and late Givetian S. (S.) sp.n. (unnamed for lack of sufficient material). Morphotypes referable to S. (S.) schnuri biscissa and to S. (S.) schnuri junkerbergiana co-occur in the same outcrop (not necessarily in the same levels), wherefore the separation of these subspecies may be maintained only if they are considered as chronosubspecies (unverifiable on the studied material) but not as geographic variants (hypothesis falsified by the studied material). A lectotype for S. (S.) interstrialis and a neotype for S. (S.) parvaepunctata are selected. Punctae diameter and density (either an important systematic character according to some authors or devoid of such value according to other ones) were investigated: they show important within-individual and within-sample variation, wherefore they cannot serve to distinguish related species. On the contrary, punctae character combinations are sufficiently constant to help differentiate subgenera or groups of species. In the studied material, three clusters are distinguished on the basis of the punctae characteristics: S. (Pachyschizophoria) and S. (S.) parvaepunctata differ between each other and from all other investigated species of S. (Schizophoria); the latter are indistinguishable on the sole basis of punctae characteristics.     

Ticks of the Central African Republic

A review is presented of the ticks of the Central African Republic (C.A.R.), based on unpublished data and a literature review. We consider as established in the C.A.R. two species of Argasidae (one species of each of the genera Carios and Ornithodoros) and 49 species of Ixodidae: 5 Ixodes, 11 Amblyomma, 2 Dermacentor, 9 Haemaphysalis, 4 Hyalomma, and 18 Rhipicephalus species, 3 of which belong to the subgenus Boophilus. Two of these species, one Amblyomma and one Dermacentor, may by now have disappeared from the country together with their hosts, the black and white rhinoceroses. Moreover, four other species of Ixodidae have been recorded, but are not necessarily established in the country, and 6 species of Ixodidae have apparently been reported incorrectly; the data for the occurrence of three other species of Ixodidae are uncertain. Rhipicephalus species in the C.A.R. present the greatest difficulties in identification, on the one hand because of uncertainties in taxonomy, particularly in the capensis group, on the other hand because of individual variability, which means that individual specimens cannot always be reliably identified to species. Examining the dissected and cleared gonopore structure of females helps, but is very time-consuming where large numbers are involved. Some of the species of the genus Haemaphysalis are also difficult to identify with certainty. There are only a few species of Hyalomma in the country. We revised also some old records of ticks in C.A.R., which we consider as unreliable and should be disregarded because of subsequent changes in taxonomy and nomenclature, unless the material is still available for examination.     

The first report describes features of the chloroplast genome of Withania frutescens

Genomic studies not only help researcher not only to identify genomic features in organisms, but also facilitate understanding of evolutionary relationships. Species in the Withania genus have medicinal benefits, and one of them is Withania frutescens, which is used to treat various diseases. This report investigates the nucleotides and genic features of chloroplast genome of Withania frutescens and trying to clarify the evolutionary relationship with Withania sp and family Solanaceae. We found that the total size of Withania frutescens chloroplast genome was 153.771 kb (the smallest chloroplast genome in genus Withania). A large single-copy region (91.285 kb), a small single-copy region (18.373 kb) form the genomic region, and are distinct from each other by a large inverted repeat (22.056 kb). 137 chloroplast genes are found including 4 rRNAs, 38 tRNAs and 83 protein-coding genes. The Withania frutescens chloroplast genome as well as four closest relatives was compared for features such as structure, nucleotide composition, simple sequence repeats (SSRs) and codon bias. Compared to other Withania species, Withania frutescens has unique characteristics. It has the smallest chloroplast genome of any Withania species, isoleucine is the major amino acid, and tryptophan is the minor, In addition, there are no ycf3 and ycf4 genes, fourth, there are only fifteen replicative genes, while in most other species there are more. Using fast minimum evolution and neighbor joining, we have reconstructed the trees to confirm the relationship with other Solanacaea species. The Withania frutescens chloroplast genome is submitted under accession no. ON153173.     

Discrimination Between Mesophilic and Psychrotolerant Strains in the Bacillus cereus Group Based on the PstI Digestion of the pycA Gene

A simple and rapid assay for the detection of Bacillus weihenstephanensis isolates and other psychrotolerant strains in the Bacillus cereus group was developed. It is based on the presence of a nucleotide substitution at position 795 on the housekeeping pycA gene in all B. weihenstephanensis strains. This mutation creates a PstI recognition site. It is absent in mesophilic strains in the B. cereus group. The pycA gene is amplified by PCR and the amplicons submitted to PstI digestions. In mesophilic strains, a single band of 1,718 bp in length is visualised on an agarose gel. In B. weihenstephanensis strains and in all other psychrotolerant strains from the B. cereus group, the amplicons are cleaved and two bands of 1,175 and 543 bp, respectively, are visualised. This method could be used for the screening of B. cereus collections and for the identification of psychrotolerant and mesophilic isolates from different environments.     

Alarm pheromones in the genus Manica derived from the mandibular gland

The alarm pheromones present in the mandibular glands of Manica mutica and M. bradleyi are dominated by a novel C₁₀ ketone, 4,6-dimethyl-4-octene-3-one (manicone). Two other new insect pheromones, 4-methyl-3-hexanone and 3-decanone, are also present. In addition, two characteristic myrmicine alarm pheromones, 3-octanone and 4-methyl-3-heptanone, have been identified as mandibular gland constituents. While manicone functions as a powerful releaser of alarm behaviour for Manica workers a much weaker response was obtained to the other identified 3-alkanones. The significance of the occurrence of 3-ketones in members of the genus Manica and species in other genera of the Myrmicinae is analysed in terms of the accepted phylogeny of this subfamily.     

The Small GTP-Binding Proteins AgRho2 and AgRho5 Regulate Tip-Branching,Maintenance of the Growth Axis and Actin-Ring-Integrity in the Filamentous Fungus Ashbya gossypii

GTPases of the Rho family are important molecular switches that regulate many basic cellular processes. The function of the Rho2 and Rho5 proteins from Saccharomyces cerevisiae and of their homologs in other species is poorly understood. Here, we report on the analysis of the AgRho2 and AgRho5 proteins of the filamentous fungus Ashbya gossypii. In contrast to S. cerevisiae mutants of both encoding genes displayed a strong morphological phenotype. The Agrho2 mutants showed defects in tip-branching, while Agrho5 mutants had a significantly decreased growth rate and failed to maintain their growth axis. In addition, the Agrho5 mutants had highly defective actin rings at septation sites. We also found that a deletion mutant of a putative GDP-GTP-exchange factor (GEF) that was homologous to a Rac-GEF from other species phenocopied the Agrho5 mutant, suggesting that both proteins act in the same pathway, but the AgRho5 protein has acquired functions that are fulfilled by Rac-proteins in other species.     

Steps towards a phylogeny of the pill millipedes: non-monophyly of the family Protoglomeridae,with an integrative redescription of Eupeyerimhoffia archimedis (Diplopoda,Glomerida)

Eupeyerimhoffia archimedis (Strasser, 1965) is redescribed based on several specimens collected at a number of sites close to the type locality on Sicily, Italy. Scanning electron microscopy is used to illustrate several unusual morphological characters for a member of the Glomerida for the first time. A fragment of the mitochondrial COI gene (668bp) is sequenced for the first time in Eupeyerimhoffia to provide a species-specific barcode and to gain first insights into the genetic distances between the genera in the widespread family Protoglomeridae. The novel sequences are compared to representatives of all other genera of the family: Protoglomeris vasconica (Brölemann, 1897) from northern Spain, the dwarfed Glomerellina laurae Silvestri, 1908 from Italy and Glomeroides primus (Silvestri, 1929) from western North America. The addition of COI sequences from the two other families of the Glomerida renders the family Protoglomeridae paraphyletic with Glomeroides primus being more closely related to Glomeridella minima (Latzel, 1884) than to the other genera in the family. The large genetic distances (13.2–16.8%) between Eupeyerimhoffia and the other genera in the order, as well as its unusual morphological characters, including unique morphological adaptations to roll into a ball, are probably an indication of the old age of the group.     

Organization of the nar genes at the chlZ locus

The two membrane-bound respiratory nitrate reductases of Escherichia coli are encoded by distinct operons at two different loci, chlC and chlZ, on the chromosome. The chlZ locus includes a narK homologue, narU, encoding a nitrite extrusion protein, and narZYWV encoding nitrate reductase Z. No apparent homologue to the narXL operon has been found. Homology between narU and narK on the one hand and narZYWV and narGHJI on the other hand is limited to the coding regions.     

Nomenclatural Revision for the Order Scorzonero-Chrysopogonetalia

The order Scorzonero-Chrysopogonetalia describes the dry grasslands of a large area in southeastern Europe, centred around and east of the Adriatic Sea (i.e., Albania, Bosnia-Herzegovina, Bulgaria, Croatia, Italy, Montenegro and Slovenia). Most commonly, Scorzonero-Chrysopogonetalia is arranged within the classes Festuco-Brometea or Brachypodio-Chrysopogonetea or it is split into two orders classified within Festuco-Brometea and Thero-Brachypodietea; according to other minor opinions, the order is sometimes assigned to Brachypodio-Brometea, Thero-Brachypodietea or Ononido-Rosmarinetea. This report deals with the nomenclatural revision of Scorzonero-Chrysopogonetalia and other correlated syntaxa to sort out the numerous incorrect syntaxon names found in scientific literature. The revision is carried out according to the third edition of the International Code of Phytosociological Nomenclature, and while it focuses on ranks of order, alliance and suballiance, it is also enlarged to include associations quoted in major comprehensive syntaxonomic revisions. As a result, many names and authors’ citations of syntaxa are corrected, and the theoretical implications arising from their usage are indicated. To promote nomenclatural stability, a new alliance, Violo pseudogracilis-Bromopsion caprinae, is described, and the following syntaxa are validated: Hypochoeridion maculatae, Hypochoeridenion maculatae, Astragalo croatici-Seslerietum robustae, Avenulo praeustae-Brometum erecti, Bromo erecti-Seslerietum interruptae, Carici vernae-Scabiosetum leucophyllae, Globulario cordifoliae-Scabiosetum leucophyllae, Globulario elongatae-Chrysopogonetum grylli, Minuartio capillaceae-Genistetum pulchellae, Stipo eriocaulis-Caricetum humilis and Stipo pennatae-Genistetum dalmaticae. Additionally, three association names (Asphodelo albi-Filipenduletum vulgaris, Centaureo rupestris-Caricetum humilis and Cymbopogono hirti-Brachypodietum ramosi) are proposed for inversions, and three others (Festuco illyricae-Poetum bulbosae, Lactuco vimineae-Bothriochloetum ischaemum and Saturejo montanae-Dichanthietum ischaemum) are corrected. Finally, typifications of 16 syntaxa are given.