<Emphasis Type="Italic">Ty</Emphasis>1<Emphasis Type="Italic">/copia</Emphasis>- and <Emphasis Type="Italic">Ty</Emphasis>3<Emphasis Type="Italic">/gypsy</Emphasis>-like DNA sequences in <Emphasis Type="Italic">Helianthus </Emphasis>species

Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.     

Revision of the <Emphasis Type="Italic">Serrulati</Emphasis> species of <Emphasis Type="Italic">Penstemon</Emphasis> section <Emphasis Type="Italic">Saccanthera</Emphasis> subsection <Emphasis Type="Italic">Serrulati</Emphasis>

A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.     

<Emphasis Type="Italic">Galleria</Emphasis><Emphasis Type="Italic">mellonella</Emphasis> are Resistant to <Emphasis Type="Italic">Pneumocystis</Emphasis><Emphasis Type="Italic">murina</Emphasis> Infection

Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.     

<Emphasis Type="Italic">Agrobacterium</Emphasis><Emphasis Type="Italic">tumefaciens</Emphasis>-mediated transformation of callus cells of <Emphasis Type="Italic">Crataegus</Emphasis><Emphasis Type="Italic">aronia</Emphasis>

A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l⁻¹ Indole-3-butyric acid (IBA) and 0.5 mg l⁻¹ 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l⁻¹ 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l⁻¹ kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l⁻¹ hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.     

Identification of <Emphasis Type="Italic">S</Emphasis> haplotypes in <Emphasis Type="Italic">Brassica</Emphasis> by dot-blot analysis of <Emphasis Type="Italic">SP11</Emphasis> alleles

A self-incompatibility system is used for F(1) hybrid breeding in Brassicaceae vegetables. The determinants of recognition specificity of self-incompatibility in Brassica are SRK in the stigma and SP11/SCR in the pollen. Nucleotide sequences of SP11 alleles are more highly variable than those of SRK. We analyzed the S haplotype specificity of SP11 DNA by Southern-blot analysis and dot-blot analysis using 16 S haplotypes in Brassica oleracea, and found that DNA fragments of a mature protein region of SP11 cDNA, SP11(m), of eight S haplotypes can detect only the SP11 alleles of the same S haplotypes. This specificity makes these methods useful for S haplotype identification. Therefore, we developed two methods of dot-blot analysis for SP11. One is dot blotting of DNA samples, i.e. plant genomic DNA probed with labeled SP11(m), and the other is dot blotting of SP11(m) DNA fragments probed with labeled DNA samples, i.e. the SP11 coding region labeled by PCR using a template of plant genomic DNA. The former is useful for testing many plant materials. The latter is suitable, if there is no previous information on the S haplotypes of plant materials.     

The <Emphasis Type="Italic">Caenorhabditis</Emphasis><Emphasis Type="Italic">briggsae</Emphasis> genome contains active <Emphasis Type="Italic">CbmaT1</Emphasis> and <Emphasis Type="Italic">Tcb1</Emphasis> transposons

The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.     

Functional conservation of the human <Emphasis Type="Italic">EXT1</Emphasis> tumor suppressor gene and its <Emphasis Type="Italic">Drosophila</Emphasis> homolog <Emphasis Type="Italic">tout</Emphasis><Emphasis Type="Italic">velu</Emphasis>

Heparan sulfate proteoglycans play a vital role in signaling of various growth factors in both Drosophila and vertebrates. In Drosophila, mutations in the tout velu (ttv) gene, a homolog of the mammalian EXT1 tumor suppressor gene, leads to abrogation of glycosaminoglycan (GAG) biosynthesis. This impairs distribution and signaling activities of various morphogens such as Hedgehog (Hh), Wingless (Wg), and Decapentaplegic (Dpp). Mutations in members of the exostosin (EXT) gene family lead to hereditary multiple exostosis in humans leading to bone outgrowths and tumors. In this study, we provide genetic and biochemical evidence that the human EXT1 (hEXT1) gene is conserved through species and can functionally complement the ttv mutation in Drosophila. The hEXT1 gene was able to rescue a ttv null mutant to adulthood and restore GAG biosynthesis.     

Functional Characteristics of <Emphasis Type="Italic">Lactobacillus</Emphasis><Emphasis Type="Italic">fermentum</Emphasis> F1

In this study, Lactobacillus fermentum (L. fermentum) F1 reduced cholesterol 48.87%. The strain was screened from cattle feces using an API 50 CHL system and the 16S rRNA sequence contrasting method. L. fermentum F1 showed acid and bile tolerance, and antimicrobial activity against pathogenic Escherichia coli and Staphylococcus aureus. L. fermentum F1 deconjugated 0.186 mM of free cholalic acid after it was incubated at 37°C in 0.20% sodium taurocholate (TCA) broth for 24 h. Heat-killed and resting cells of L. fermentum F1 showed small amounts of cholesterol removal (6.85 and 25.19 mg/g, respectively, of dry weight) compared with growing cells (33.21 mg/g of dry weight). The supernatant fluid of the broth contained 50.85% of the total cholesterol, while the washing buffer and cell extracts had 13.53 and 35.39%, respectively. These findings suggest that L. fermentum F1 may remove cholesterol by co-precipitating with deconjugated bile salt, assimilating with cells and by incorporation into cellular membranes. Cholesterol assimilated by cells held 72.0% of the reduced cholesterol, while 21.65% of the reduced cholesterol was coprecipitated with deconjugated bile salt and 5.89% was adsorbed into the surface of the cells.     

In planta transformation of <Emphasis Type="Italic">Notocactus scopa</Emphasis> cv. <Emphasis Type="Italic">Soonjung</Emphasis> by <Emphasis Type="Italic">Agrobacterium </Emphasis><Emphasis Type="Italic">tumefaciens</Emphasis>

Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.     

<Emphasis Type="Italic">IGHV1</Emphasis>,<Emphasis Type="Italic"> IGHV5</Emphasis> and<Emphasis Type="Italic"> IGHV7</Emphasis> subgroup genes in the Rhesus macaque

The diversity of the antibody response is achieved, in part, by rearrangement of different immunoglobulin (Ig) genes. The Ig heavy chain is made up of a variable region (IGHV), a diversity region (IGHD) and a joining region (IGHJ). Human germline IGHV genes have been grouped into seven multigene subgroups. Size and usage of these subgroups is not equal, the IGHV3 subgroup is the most commonly used (36%), followed by IGHV1/7 (26%), then IGHV4, IGHV5, IGHV2, IGHV6 (15%, 12%, 4%, 3% respectively). The rhesus macaque (Macaca mulatta) is a useful non-human primate model for studies of infection and the database of germline Ig genes for the macaque is gradually growing to become a useful tool in the study of B-cell responses. The proportions of IGHV subgroup usage in the macaque are similar to those in man. Representatives from IGHV3 and IGHV4 subgroups for the macaque have been published, as have germline sequences of the IGHD and IGHJ genes. However, to date there have been no sequences published from the second largest IGHV subgroup, IGHV1. We report the isolation and sequencing of a genomic fragment containing an IGHV1 gene from the macaque. Polymerase chain reaction (PCR) primers designed from this sequence enabled us to amplify and sequence 25 new IGHV1 germline genes. We also isolated two IGHV7 genes, using the same primers, and two IGHV5 genes, using human IGHV5 primers.     

<Emphasis Type="Italic">MlAG12</Emphasis>: a <Emphasis Type="Italic">Triticum timopheevii</Emphasis>-derived powdery mildew resistance gene in common wheat on chromosome 7AL

Wheat powdery mildew is an economically important disease in cool and humid environments. Powdery mildew causes yield losses as high as 48% through a reduction in tiller survival, kernels per head, and kernel size. Race-specific host resistance is the most consistent, environmentally friendly and, economical method of control. The wheat (Triticum aestivum L.) germplasm line NC06BGTAG12 possesses genetic resistance to powdery mildew introgressed from the AAGG tetraploid genome Triticum timopheevii subsp. armeniacum. Phenotypic evaluation of F₃ families derived from the cross NC06BGTAG12/‘Jagger’ and phenotypic evaluation of an F₂ population from the cross NC06BGTAG12/‘Saluda’ indicated that resistance to the ‘Yuma’ isolate of powdery mildew was controlled by a single dominant gene in NC06BGTAG12. Bulk segregant analysis (BSA) revealed simple sequence repeat (SSR) markers specific for chromosome 7AL segregating with the resistance gene. The SSR markers Xwmc273 and Xwmc346 mapped 8.3 cM distal and 6.6 cM proximal, respectively, in NC06BGTAG12/Jagger. The multiallelic Pm1 locus maps to this region of chromosome 7AL. No susceptible phenotypes were observed in an evaluation of 967 F₂ individuals in the cross NC06BGTAG12/‘Axminster’ (Pm1a) which indicated that the NC06BGTAG12 resistance gene was allelic or in close linkage with the Pm1 locus. A detached leaf test with ten differential powdery mildew isolates indicated the resistance in NC06BGTAG12 was different from all designated alleles at the Pm1 locus. Further linkage and allelism tests with five other temporarily designated genes in this very complex region will be required before giving a permanent designation to this gene. At this time the gene is given the temporary gene designation MlAG12.     

New combinations and typifications in <Emphasis Type="Italic">Bistorta</Emphasis>, <Emphasis Type="Italic">Persicaria</Emphasis>, <Emphasis Type="Italic">Polygonum,</Emphasis> and <Emphasis Type="Italic">Rumex</Emphasis> (Polygonaceae)

New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.     

Association of <Emphasis Type="Italic">iceA</Emphasis> and <Emphasis Type="Italic">babA</Emphasis> genotypes in <Emphasis Type="Italic">Helicobacter pylori</Emphasis> strains with patient and strain characteristics

Data on the geographic prevalence of Helicobacter pylori iceA and babA alleles in Eastern Europe are still relatively scant. The aim of this study was to evaluate the prevalence of iceA and babA genotypes in Bulgarian symptomatic patients. The iceA and babA genotypes were evaluated by PCR with pure cultures in strains from 196 and 181 patients, respectively. Mixed infections were found in 10.2% of all 196 patients. Prevalence of H. pylori genotypes in patients with single-strain infections was 69.3% for iceA1, 30.7% for iceA2, 82.4% for cagA ⁺, 89.2% for vacA s1, 10.8% for vacA s2, 39.8% for vacA m1, 60.2% for vacA m2 and 48.8% for babA2. Within the iceA1 positive strains, 94.3% and 88.5% were also vacA s1a and cagA positive, respectively. Of the babA2 positive strains, 100.0%, 92.4% and 72.2% were also vacA s1a, cagA and iceA1 positive, respectively. Ulcer patients had more often strains with cagA positive status and vacA s1a allele. Although neither iceA1 nor babA2 were more common in ulcer patients, the combination of both alleles was more frequent (48.1%) in the ulcer patients than in the rest (28.7%). Clarithromycin susceptible strains had more often iceA1 allele (74.4%) than the resistant strains (55.3%). In conclusion, the results demonstrated a high prevalence of virulent H. pylori in Bulgaria. Both iceA1 and babA2 genotypes were associated with other virulence factors of H. pylori and, in addition, the iceA1 allele was associated with the strain susceptibility.     

Phenotypic Switching of <Emphasis Type="Italic">Cryptococcus neoformans</Emphasis> and <Emphasis Type="Italic">Cryptococcus</Emphasis><Emphasis Type="Italic">gattii</Emphasis>

Microorganisms that live in fluctuating environments must constantly adapt their behavior to survive. The host constitutes an important microenvironment in opportunistic and primary fungal pathogens like Cryptococcus neoformans (C. neoformans) and Cryptococcus gattii (C. gattii). In clonal populations, adaptation may be achieved through the generation of diversity. For fungi phenotype switching constitutes a mechanism that allows them to change rapidly. Both C. neoformans and C. gattii undergo phenotypic switching, which allows them to be successful pathogens and cause persistent disease. Similar to other encapsulated microbes that exhibit phenotypic variation, phenotypic switching in Cryptococcus changes the polysaccharide capsule. Most importantly, in animal models phenotypic switching affects virulence and can change the outcome of infection. Virulence changes because C. neoformans and C. gattii switch variants elicit different inflammatory responses in the host. This altered host response can also affect the response to antifungal therapy and in some cases may even promote the selection of switch variants. This review highlights the similarity and differences between phenotypic switching in C. neoformans and C. gattii, the two dominant species that cause cryptococcosis in humans.     

A new methanol assimilating yeast, <Emphasis Type="Italic">Ogataea</Emphasis><Emphasis Type="Italic">parapolymorpha</Emphasis>, the ascosporic state of <Emphasis Type="Italic">Candida</Emphasis><Emphasis Type="Italic">parapolymorpha</Emphasis>

Ogataea parapolymorpha sp. n. (NRRL YB-1982, CBS 12304, type strain), the ascosporic state of Candida parapolymorpha, is described. The species appears homothallic, assimilates methanol as is typical of most Ogataea species and forms hat-shaped ascospores in asci that become deliquescent. O. parapolymorpha is closely related to Ogataea angusta and Ogataea polymorpha. The three species can be resolved from gene sequence analyses but are unresolved from fermentation and growth reactions that are typically used for yeast identification. On the basis of multiple isolates, O. angusta is known only from California, USA, in association with Drosophila and Aulacigaster flies, O. parapolymorpha is predominantly associated with insect frass from trees in the eastern USA but O. polymorpha has been isolated from various substrates in the USA, Brazil, Spain and Costa Rica.     

<Emphasis Type="Italic">Diplazium</Emphasis> hybrids involving <Emphasis Type="Italic">D. plantaginifolium</Emphasis> and <Emphasis Type="Italic">D</Emphasis>. <Emphasis Type="Italic">ternatum</Emphasis> from Mexico and Central America

Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.