Chrysocapsopsis rupicola: A new genus and species in the Chrysophyceae

Chrysocapsopsis rupicola gen. et sp. nov. (Chrysophyceae) is described. It differs from Chrysocapsa and the closely related genera Chrysocapselia and Tetrachrysis by possessing both epiphytic and planktonic forms within the same life-history. Reproduction is by budding which produces short irregular branches within a gelatinous mass. Four or more aplanospores are produced from each mother cell; no motile cells were observed.     

A myrtenylfuroheliangolide from Calea rupicola

The aerial parts of Calea rupicola afforded in addition to known furoheliangolides two new ones, 9α-hydroxyatripliciolide-8-O-isobutyrate and a myrtenyl substituted sesquiterpene lactone 5β-myrtenyl-4α,5-dihydroatripliciolide-8-O-isovalerate.     

Seed germination in the Sicilian subspecies of Dianthus rupicola Biv. (Caryophyllaceae)

Abstract

Five populations belonging to three subspecies of Dianthus rupicola Biv. (D. rupicola subsp. rupicola, D. rupicola subsp. aeolicus, and D. rupicola subsp. lopadusanus) and growing in different geographical areas of Sicily were tested for seed germination at various temperatures. All populations showed high germination rates with an optimum temperature between 15°C and 25°C. Efficient seed germination might contribute significantly to the preservation of these subspecies which are currently exposed to several environmental threats.     

A comparative study of the ecology ofFestuca valesiaca Gaudin andFestuca rupicola Heuff

The ecology of two dominant grass species growing in xerothermic grasslands of the Bohemian Karst has been compared. Field observations and experimental cultivations showed thatFestuca valesiaca Gaudin can better tolerate more extreme dry and warm conditions of southern slopes.Festuca rupicola Heuff. possesses greater competitive capacity in deeper and wetter soils. Young seedlings ofF. valesiaca survice successfully the overheating of the soil surface exposed, to strong insolation.     

Lycoperdon rupicola and L. subumbrinum: two new puffballs from Europe

Lycoperdon rupicola and L. subumbrinum are here described as new species. The former is a morphologically characteristic species forming small subglobose to pyriforme fruiting bodies with a prominent, protruding and stellately lobed stoma. In the phylogenetic analyses the six sequences of L. rupicola form a clade with 100% BS and 1.0 BPP, clustering with L. dermoxanthum. The proposed species grows among mosses on siliceous boulders and flat rocks as well as on open, sandy soil in temperate and hemiboreal regions. The records to date indicate its presence in Fennoscandia and Spain (Catalunya). L. subumbrinum morphologically resembles L. umbrinum but differs in having coarser ornamentation of its spores. In the phylogenetic analyses the five sequences of L. subumbrinum form a clade with 100% BS and 1.0 BPP, clustering with L. muscorum. The records to date, originating from southernmost Sweden and NW Slovakia, indicate that L. subumbrinum is a species of rich deciduous forests. L. muscorum is recorded for the first time from the Iberian peninsula (Spain).     

High photobiont diversity associated with the euryoecious lichen-forming ascomycete Lecanora rupicola (Lecanoraceae, Ascomycota)

The diversity and phylogenetic position of photobionts in the widespread saxicolous, crustose lichen-forming ascomycete Lecanora rupicola s.l. is presented. The algal partners of this lichen species complex belong to diverse and unrelated lineages in the genus Trebouxia . Specimens were sampled from different habitats and geographical origins. Either whole thallus DNA extractions or minute fragments of the algal layer of the lichen thallus were subjected to polymerase chain reaction, using primers that specifically amplify internal transcribed spacer rDNA of the photobionts. No correlations between different chemical races of L. rupicola with particular lineages of Trebouxia spp. were found. Irrespective of the different algal partners, all lichen thalli abundantly developed ascomata. L. rupicola apparently maintains full fecundity with a low degree of selectivity for photobionts, which promotes the occurrence of this lichen-forming species in ample ecological situations.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 283–293.     

Description of the female of Evandromyia rupicola (Martins, Godoy & Silva) with a review of the rupicola series (Diptera: Psychodidae: Phlebotominae)

The rupicola series was proposed initially for Evandromyia rupicola (Martins et al) and Evandromyia correalimai (Martins et al), and recently extended with the inclusion of Evandromyia gaucha Andrade-Filho et al and Evandromyia grimaldii Andrade-Filho et al. The female of E. rupicola is here described and illustrated for the first time and its male is redescribed and drawn on the basis of specimens captured in forest on the coast of the state of S?o Paulo, Brazil. The head and genitalia of both sexes of E. correalimai are also illustrated. The distinctive traits among females of the four species and of males of E. rupicola, E. correalimai and E. grimaldii, and the distribution range of these species are commented.     

The new species Lecanora bicinctoidea, its position and considerations about phenotypic evolution in the Lecanora rupicola group

A phylogenetic analysis of the Lecanora rupicola group based on combined nITS rDNA and beta-tubulin sequences and a combined dataset of ITS, beta-tubulin and partial sequences of polyketide synthase genes reveals a previously unrecognized species, which here is introduced under the name Lecanora bicinctoidea. The new species is a sister group of the L. swartzii complex (including L. swartzii and L. lojkaeana), which is characterized by eucorticate ascomata, and a morphological diversity that includes also a dwarf-fruticose lineage. The preferential occurrence on vertical to overhanging siliceous rocks corresponds more closely to L. swartzii. A detailed investigation of phenotypic characters reveals that the new species differs from the superficially similar morphospecies L. bicincta in several ways, such as a thallus of comparatively small areoles and broadly sessile ascomata and the development of an amphithecial cortex devoid of algal remnants (i.e. an eucortex). L. bicinctoidea contains methyl 3alpha-hydroxy-4-O-demethylbarbatate, a chemical compound not known from other members of the L. rupicola group. We also discuss the importance of eucortex formation as one of several factors that are involved in the evolution of substrate-detached thallus structures.     

Methyl directed DNA mismatch repair inVibrio cholerae

Mismatches in DNA occur either due to replication error or during recombination between homologous but non-identical DNA sequences or due to chemical modification of bases. The mismatch in DNA, if not repaired, result in high spontaneous mutation frequency. The repair has to be in the newly synthesized strand of the DNA molecule, otherwise the error will be fixed permanently. Three distinct mechanisms have been proposed for the repair of mismatches in DNA in prokaryotic cells and gene functions involved in these repair processes have been identified. The methyl-directed DNA mismatch repair has been examined inVibrio cholerae, a highly pathogenic gram negative bacterium and the causative agent of the diarrhoeal disease cholera. The DNA adenine methyltransferase encoding gene (dam) of this organism which is involved in strand discrimination during the repair process has been cloned and the complete nucleotide sequence has been determined.Vibrio cholerae dam gene codes for a 21.5 kDa protein and can substitute for theEscherichia coli enzyme. Overproduction ofVibrio cholerae Dam protein is neither hypermutable nor lethal both in Escherichia coli andVibrio cholerae. WhileEscherichia coli dam mutants are sensitive to 2-aminopurine,Vibrio cholerae 2-aminopurine sensitive mutants have been isolated with intact GATC methylation activity. The mutator genesmutS andmutL involved in the recognition of mismatch have been cloned, nucleotide sequence determined and their products characterized. Mutants ofmutS andmutL ofVibrio cholerae have been isolated and show high rate of spontaneous mutation frequency. ThemutU gene ofVibrio cholerae, the product of which is a DNA helicase II, codes for a 70 kDa protein. The deduced amino acid sequence of themutU gene hs all the consensus helicase motifs. The DNA cytosine methyltransferase encoding gene (dam) ofVibrio cholerae has also been cloned. Thedcm gene codes for a 53 kDa protein. This gene product might be involved in very short patch (VSP) repair of DNA mismatches. The vsr gene which is directly involved in VSP repair process codes for a 23 kDa protein. Using these information, the status of DNA mismatch repair inVibrio cholerae will be discussed.     

Quantitative analysis of the redox states of cytochromes in a living L929 (NCTC) cell by resonance Raman microspectroscopy

Raman spectra and images of a living L929 (NCTC) cell have been measured with 532 nm excitation. Both reduced and oxidized forms of cytochromes b and c (cyt b and cyt c) have been observed in situ without any pretreatment. The redox states of cyts b and c have been assessed quantitatively with a spectral analysis. It has been found that reduced cyt c is more abundant than oxidized cyt c, while oxidized cyt b is slightly more abundant than reduced cyt b in a living cell. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Reporter genes in transgenic mice

Althoughin vivo models utilizing endogenous reporter genes have been exploited for many years, the use of reporter transgenes to dissect biological issues in transgenic animals has been a relatively recent development. These transgenes are often, but not always, of prokaryotic origin and encode products not normally associated with eukaryotic cells and tissues. Some encode enzymes whose activities are detected in cell and tissue homogenates, whereas others encode products that can be detectedin situ at the single cell level. Reporter genes have been used to identify regulatory elements that are important for tissue-specific gene expression or for development; they have been used to producein vivo models of cancer; they have been employed for the study ofin vivo mutagenesis; and they have been used as a tool in lineage analysis and for marking cells in transplanation experiments. The most commonly usedin situ reporter gene islacZ, which encodes a bacterial -galactosidase, a sensitive histochemical marker. Although it has been used with striking success in cultured cells and in transgenic mouse embryos, its postnatalin vivo expression has been unreliable and disappointing. Nevertheless, the ability to express reporter genes in transgenic mice has been an invaluable resource, providing insights intoin vivo biological mechanisms. The development of newin vivo models, such as those in which expression of transgenes can be activated or repressed, should produce transgenic animal systems that extend our capacity to address heretofore unresolved biological questions.     

Two new genes involved in signalling ambient pH in Aspergillus nidulans

Two new genes, palH and palI, where mutations mimic the effects of acidic growth pH have been identified in Aspergillus nidulans. A palH mutation is phenotypically indistinguishable from mutations in the palA, palB, palC, and palF genes, whereas palI mutations differ only in that they allow some growth at pH 8. Mutations in palA, B, C, F, and H are epistatic to a palI mutation and the significance of this epistasis is discussed. Additionally, palE and palB mutations have been shown to be allelic. Thus, a total of six genes where mutations mimic acidic growth conditions has been identified.     

The Horse Chestnut Lines Harboring the rol Genes

An Agrobacterium rhizogenes-mediated transformation system for Aesculus hippocastanum L. has been developed. Wounded androgenic embryos of A. hippocastanum were inoculated with bacteria containing the pRiA4 plasmid, with the uid A sequence as a reporter gene. The hairy roots emerging from the wounded sites of androgenic embryos were isolated and maintained in Murashige and Skoog's (MS) liquid hormone-free medium. Five hairy root lines have been maintained in vitro for 4 years with unchanged growth rate and might be a suitable source for secondary metabolite production. The transformation events have been confirmed by a polymerase chain reaction specific to the rol A, B, C and D genes. The absence of residual contaminating bacteria has been shown by a polymerase chain reaction specific to the vir D1 sequence.     

Fouling Communities of Hydrotechnical Constructions in Nakhodka Bay (Sea of Japan)

The fouling of mooring facilities in Nakhodka Bay, Sea of Japan, has been studied. The main fouling communities have been distinguished dominated by green algae Enteromorpha linza and Ulva fenestrata, brown algae Laminaria japonica and Costaria costata, a hydroid Obelia longissima, a polychaete Pseudopotamilla occelata, cirripede barnacles Balanus crenatus and Semibalanus cariosus, a bivalve mollusk Mytilus trossulus, and an ascidian Halocynthia aurantium. The naturalization of some species-invaders in the fouling of mooring facilities in Nakhodka Bay has been registered, namely hydroids Laomedea flexuosa and Clytia languida, a polychaete Pseudopotamilla occelata, and a bryozoan Bowerbankia gracilis.     

Alcuni Aspetti Della Variabilità Del Legno Secondario Di Un Esemplare Di Prunus Persica Stokes

Abstract

Some aspects of the variability in wood structure of a specimen of PRUNUS PERSICA Stokes. — The secondary xylem of a young stem of Prunus persica Stokes has been investigated under three main headings: 1) vessel and fibre length; 2) intrusive fibre growth; 3) relative amount of libriform fibres, fibretracheids and tracheids.

Vessel members and fibres have been reckoned from single rings and from the whole wood body.

The relation between the above mentioned dimensions and the position within the wood body and the width of the growth layers has been calculated.

No remarkable variation has been found along the axis of the stem; on the contrary there is a decrease in both fibres and vessels length along the radius of the stem from inside outwards. Such behaviour having never been recorded before, the possible causes are suggested.

A positive correlation has been found between the width of the growth layers and 1) vessel members and fibres length, 2) fibre intrusive growth, 3) percentage of libriform fibres. In addition a relative correlation between percentage of libriform fibres and age of the cambium has been put in evidence.     

The Non-Random Pattern of Insertion of IS2 into the hemB Gene of Escherichia coli

The hemB gene of Escherichia coli has been identified as a hot spot for the insertion of the transposable element IS2. The insertional specificity of IS2 is still unclear. This study reports on the attempt to sequence a statistically significant number of insertions in hemB, in order to determine whether there might be a basis for future studies to determine a molecular basis of IS2 insertional specificity. The results indicate that IS2 inserts in a non-random manner into a 240 bp segment at the 5′ end of the gene (region I). Twenty-one of 24 insertions occurred in region I. Three insertions have been identified in the two middle 250 bp segments of the 975 bp gene, and none in the 3′ terminal segment. A seventeen bp sequence showing 88.2% identity with a segment of IS2, 221 bp from the 3′ terminus has been identified in region I. Four instances of repeated insertion between the same pair of nucleotides have been observed at four different sites.     

The use of transgenic and naturally occurring mutants to understand and manipulate tomato fruit ripening

In the years since we last reviewed the use of mutants to study tomato fruit ripening ( Grierson et al. 1987 ), considerable information has been gained by the cloning, sequencing and identification of many mRNAs implicated in this developmental process. Genes involved in cell wall degradation, colour change and ethylene synthesis have been cloned, and antisense techniques have been developed and used to produce genetically engineered mutant fruit deficient in these aspects of ripening (see Gray et al. 1992 ). Recently, a previously cloned ripening gene has been used to complement a naturally occurring fruit colour mutant, yellow flesh ( Fray & Grierson 1993a ), and a ripening impaired mutant, ripening inhibitor, has been used to identify several new ripening-related mRNAs ( Picton et al. 1993b ). The chromosomal region bearing the ripening inhibitor mutation has been subjected to high-resolution mapping ( Churchill, Giovannoni & Tanksley 1993 ) and chromosome walking experiments are in progress to identify this gene.     

Foraging behaviour of the parasitoid Lysiphlebus testaceipes (Hymenoptera: Braconidae) in response to plant volatiles,with reference to biocontrol of aphids in peri-urban vegetable production systems

Foraging behaviour of Lysiphlebus testaceipes was studied in a Y-tube olfactometer. Naïve females responded to the Aphis gossypii/eggplant complex on which they had been reared, but did not show a preference for this aphid/plant complex over an uninfested eggplant, an eggplant that had been damaged by the aphid or an A. gossypii/okra complex. Females that had been allowed to forage on the A. gossypii/eggplant complex before being tested in the olfactometer showed a strong preference for an uninfested eggplant over an uninfested okra plant and for the A. gossypii/eggplant complex over an A. gossypii/okra complex, indicating that they had learned to associate eggplant-derived volatiles with host availability. When females that had been reared on the A. gossypii/eggplant complex were tested after foraging experience on the A. gossypii/okra complex, they did not show a preference for either complex, suggesting that they still retained a memory of the cues associated with the complex on which they had been reared. The efficiency of L. testaceipes as a biological control agent in peri-urban vegetable production, such as the Cuban organoponics system, potentially could be improved by producing and releasing females behaviourally primed to prefer specific host/plant complexes.     

Genetics of esterases in Drosophila of the virilis group. I. Characteristics of esterase patterns in D. virilis,D. texana,D. littoralis,and their hybrids

Starch and polyacrylamide gel electrophoreses have detected six esterase fractions in Drosophila of the virilis group. These esterases have been characterized in detail using a series of substrates and inhibitors and also thermal treatment. Differences in esterase patterns have been found between D. virilis, D. texana, and D. litoralis as well as between D. virilis stocks. An interstock polymorphism for different esterase patterns has been established with respect to the electrophoretic mobilities of a number of esterase fractions. In rare instances, it has been observed within some D. virilis stocks, too. There is specificity in organ distribution of esterase fractions in Drosophila. Monogenic control of the electrophoretic mobilities of esterase-2 and esterase-4 has been demonstrated in D. virilis, and a dimer structure has been found in esterase-2. Genes controlling esterase-2 and esterase-4 are located on the second chromosome (209.3 for esterase-2 and 192.0 for esterase-4). In interstock and interspecific hybrids, esterases usually manifest codominance. In interstock hybrids, esterase-2 forms a hybrid band not observed in interspecific hybrids. In third instar larvae of interspecific hybrids, differential expression of certain esterase isozymes has been noted. These observations are in agreement with data from histochemical studies of organs of different hybrids.