bluuebunny/crossref_metadata_2025 huggingface dataset:
A comparison between non‐destructive and destructive testing of Atlantic salmon, Salmo salar L., broodfish for IPNV – destructive testing is still the best at time of maturation
Authors: Munro E S , Ellis A E
Published: February 2008

Two populations of Atlantic salmon broodstock, previously identified as infectious pancreatic necrosis virus (IPNV) carriers, were screened for IPNV at the time of stripping. Four hundred and ten broodfish were individually sampled of which 91 were detected as IPNV positive by virus culture of sonicated kidney homogenates combined with gonadal fluid, but none tested positive by the blood leucocyte assay. Thirty fish identified as IPNV carriers prior to maturation by the blood leucocyte assay were used in a separate study to compare non‐destructive vs. destructive testing methods at stripping. IPNV was not detected using the blood leucocyte method at the time of stripping. RT‐PCR and real‐time PCR assays failed to detect IPNV from 13 blood samples, the virus was not isolated from milt (0/14) or sonicated ovarian fluid cell pellets (0/16) and only three fish tested positive by the standard culture of kidney homogenates. A third study of Atlantic salmon broodfish compared the IPNV isolation rates prior to maturation with the isolation rates at spawning during 1999–2001. In each year the percentage of IPNV‐positive broodfish was significantly lower than in the pre‐broodstock sample. While in pre‐broodfish samples IPNV was detected by the blood leucocyte assay, no culture isolations or PCR positives were detected from non‐destructive samples of the same individual broodfish at stripping. A consistent finding was that even for the kidney assay, the percentage of IPNV‐positive fish in carrier populations was higher in pre‐broodstock than in broodfish at stripping. These results indicate that destructive kidney sampling is still the most sensitive method for detecting IPNV carrier Atlantic salmon broodfish and that a change in IPNV carrier‐status occurs during the maturation period.
Characterization of swim bladder non‐inflation (SBN) in angelfish, Pterophyllum scalare (Schultz), and the effect of exposure to methylene blue
Authors: Perlberg S T , Diamant A , Ofir R , Zilberg D
Published: February 2008

Failure to inflate the swim bladder is regarded a major obstacle in the rearing of many fish species. We present a study of swim bladder non‐inflation (SBN) in angelfish, Pterophyllum scalare. A normal developing primordial swim bladder was first discernable at the end of the first day post‐hatch (p.h.) as a cluster of epithelial cells with a central lumen, surrounded by presumably mesenchymal cells. Initial inflation occurred on the fourth day p.h. Prior to inflation the swim bladder epithelium consisted of an outer squamous and inner columnar layer. Cells of the inner layer were filled at their basal region with an amorphous material, which disappeared upon inflation. A pneumatic duct was absent, and larvae presented no need to reach the water surface for inflation, suggesting that angelfish are pure physoclists. A model for the role of the amorphous material in normal initial inflation is proposed. Abnormal swim bladders were apparent from the fourth day p.h., and methylene blue (MB) at a concentration of 5 ppm significantly increased the prevalence of SBN. Histologically, abnormal swim bladders in larvae hatched in 5 ppm MB could not be distinguished from those in fish raised under routine conditions (0.5 ppm MB). We suggest that MB may have a teratogenic effect in angelfish.
Melatonin treatment in individuals with intellectual disability and chronic insomnia: a randomized placebo‐controlled study
Authors: Braam W. , Didden R. , Smits M. , Curfs L.
Published: February 2008

Background While several small‐number or open‐label studies suggest that melatonin improves sleep in individuals with intellectual disabilities (ID) with chronic sleep disturbance, a larger randomized control trial is necessary to validate these promising results.

Methods The effectiveness of melatonin for the treatment of chronic sleep disturbance was assessed in a randomized double‐blind placebo‐controlled trial with 51 individuals with ID. All of these individuals presented with chronic ideopatic sleep disturbance for more than 1 year. The study consisted of a 1‐week baseline, followed by 4 weeks of treatment. Parents or other caregivers recorded lights off time, sleep onset time, night waking, wake up time and epileptic seizures. Endogenous melatonin cycle was measured in saliva before and after treatment.

Results Compared with placebo, melatonin significantly advanced mean sleep onset time by 34 min, decreased mean sleep latency by 29 min, increased mean total sleep time by 48 min, reduced the mean number of times the person awoke during the night by 0.4, decreased the mean duration of these night waking periods by 17 min and advanced endogenous melatonin onset at night by an average of 2.01 h. Lights off time, sleep offset time and the number of nights per week with night waking did not change. Only few minor or temporary adverse reactions and no changes in seizure frequency were reported.

Conclusions Melatonin treatment improves some aspects of chronic sleep disturbance in individuals with ID.
Effects of a stress management program on vital exhaustion and depression in women with coronary heart disease: a randomized controlled intervention study
Authors: Koertge J. , Janszky I. , Sundin Ö. , Blom M. , Georgiades A. , László K. D. , Alinaghizadeh H. , Ahnve S.
Published: February 2008

Objectives.  Psychosocial factors, including depression and vital exhaustion (VE) are associated with adverse outcome in coronary heart disease (CHD). Women with CHD are poor responders to psychosocial treatment and knowledge regarding which treatment modality works in them is limited. This randomized controlled clinical study evaluated the effect of a 1‐year stress management program, aimed at reducing symptoms of depression and VE in CHD women.

Design.  Patients were 247 women, ≤75 years, recruited consecutively after a cardiac event and randomly assigned to either stress management (20 2‐h sessions) and medical care by a cardiologist, or to obtaining usual health care as controls. Measurements at; baseline (6–8 weeks after randomization), 10 weeks (after 10 intervention sessions), 1 year (end of intervention) and 1–2 years follow‐up.

Results.  For VE, intention to treat analysis showed effects for time (P < 0.001) and time × treatment interaction (P = 0.005), reflecting that both groups improved over time, and that the decrease of VE was more pronounced in the intervention group. However, the level of VE was higher in the intervention group than amongst controls at baseline, 22.7 vs. 19.4 (P = 0.036) but it did not differ later. The change in depressive symptoms did not differ between the groups.

Conclusions.  CHD women attending our program experienced a more pronounced decrease in VE than controls. However, as they had higher baseline levels, due to regression towards the mean we cannot attribute the decrease in VE to the intervention. Whether the program has long‐term beneficial effects needs to be evaluated.
Do troponin and B‐natriuretic peptide detect cardiomyopathy in transthyretin amyloidosis?
Authors: Suhr O. B. , Anan I. , Backman C. , Karlsson A. , Lindqvist P. , Mörner S. , Waldenström A.
Published: February 2008

Objectives.  Cardiomyopathy is a well known complication in familial amyloidotic polyneuropathy (FAP). Troponin T and B‐natriuretic peptide (BNP) have been shown to be excellent markers for heart complications in AL‐amyloidosis. The aim of the study was to investigate troponin T, troponin I and BNP as markers for myocardial damage and failure in FAP.

Design.  Retrospective investigation of patients with FAP.

Setting.  Tertiary referral centre.

Subjects.  Twenty‐nine patients who had been submitted for evaluation of FAP.

Interventions.  Two‐dimensional M‐mode and Doppler echocardiography and strain echocardiographic examination. Measurement of Troponin T, troponin I and BNP.

Results.  Troponin T was detectable in only three patients who all had abnormal interventricular septal (IVS) thickness. Troponin I was abnormal in six patients (21%), of which only two had an increased IVS thickness. The heart function was generally well preserved in the patients in spite of hypertrophy of the IVS in 14 patients. BNP was elevated in 22 patients (76%), and it correlated significantly with IVS thickness and basal septal strain.

Conclusions.  Transthyretin amyloid seems to be less harmful to myocytes than that of AL amyloid as evaluated by serum troponin T and I as well as by echocardiography. BNP appears to be a sensitive marker for cardiomyopathy in FAP, and could prove valuable for follow‐up purposes as has been shown for AL‐amyloidosis patients.
Telomere attrition is associated with inflammation, low fetuin‐A levels and high mortality in prevalent haemodialysis patients
Authors: Carrero J. J. , Stenvinkel P. , Fellström B. , Qureshi A. R. , Lamb K. , Heimbürger O. , Bárány P. , Radhakrishnan K. , Lindholm B. , Soveri I. , Nordfors L. , Shiels P. G.
Published: February 2008

Introduction.  Chronic kidney disease (CKD) predisposes to a 10‐ to 20‐fold increased cardiovascular risk. Patients undergo accelerated atherogenesis and vascular ageing. We investigated whether telomere attrition, a marker of cell senescence, contributes to this increased mortality risk.

Methods.  This is a cross‐sectional study in prevalent haemodialysis patients [n = 175; 98 Males; median (range) age: 66 (23–86) years]. Biochemical markers of oxidative stress and inflammatory status were measured in relation to the patient’s leucocyte telomere length. Overall mortality was assessed after a median of 31 (range 2–42) months.

Results.  Telomere length was shorter in CKD men, despite women being older (average ± SD 6.41 ± 1.23 vs. 6.96 ± 1.48 kb, P = 0.002). Telomere length was associated with age (rho = −0.18, P = 0.01), fetuin‐A (rho = 0.26, P = 0.0004), high‐sensitivity C‐reactive protein (rho = −0.21, P = 0.005) and IL‐6 (rho = −0.17, P = 0.02). In a multivariate logistic regression (pseudo r2 = 0.14), telomere length was associated with age >65 years (odds ratio: 2.11; 95% CI: 1.10, 4.06), sex (2.01; 1.05, 3.86), fetuin‐A (1.85; 0.97, 3.50) and white blood cell count (2.04; 1.02, 4.09). Receiver operating characteristic curves identified a telomere length < 6.28 kb as a fair predictor of mortality. Finally, reduced telomere length was associated with increased mortality, independently of age, gender and inflammation (likelihood ratio 41.6, P < 0.0001), but dependently on fetuin‐A levels.

Conclusion.  Age and male gender seem to be important contributors to reduced telomere length in CKD patients, possibly via persistent inflammation. Reduced telomere length also contributes to the mortality risk of these patients through pathways that could involve circulating levels of fetuin‐A.
Acceptability of blood and blood substitutes
Authors: Ferguson E. , Prowse C. , Townsend E. , Spence A. , Hilten J. A. van , Lowe K.
Published: February 2008

Alternatives to donor blood have been developed in part to meet increasing demand. However, new biotechnologies are often associated with increased perceptions of risk and low acceptance. This paper reviews developments of alternatives and presents data, from a field‐based experiment in the UK and Holland, on the risks and acceptance of donor blood and alternatives (chemical, genetically modified and bovine). UK groups perceived all substitutes as riskier than the Dutch. There is a negative association between perceived risk and acceptability. Solutions to increasing acceptance are discussed in terms of implicit attitudes, product naming and emotional responses.
Characterization of novel mutations in the catalytic domain of the PCSK9 gene
Authors: Cameron J. , Holla Ø. L. , Laerdahl J. K. , Kulseth M. A. , Ranheim T. , Rognes T. , Berge K. E. , Leren T. P.
Published: February 2008

Objectives.  To expand our understanding of the structure and function of proprotein convertase subtilisin/kexin type 9 (PCSK9) by studying how naturally occurring mutations in PCSK9 disrupt the function of PCSK9.

Design.  Mutations in PCSK9 were identified by sequencing of DNA from subjects with hypo‐ or hypercholesterolemia. The effect of the identified mutations on the autocatalytic cleavage and secretion of PCSK9, as well as the effect on PCSK9‐mediated degradation of the low density lipoprotein receptors, were determined in HepG2 or HEK293 cells transiently transfected with mutant PCSK9‐containing plasmids. The findings were collated to the clinical characteristics of the subjects possessing these mutations, and the phenotypic effects were analysed in terms of available structural data for PCSK9.

Results.  Five novel mutations in PCSK9 were identified. Mutation R215H was a gain‐of‐function mutation which causes hypercholesterolemia. Mutation G236S and N354I were loss‐of‐function mutations due to failure to exit the endoplasmic reticulum or failure to undergo autocatalytic cleavage, respectively. Mutations A245T and R272Q were most likely normal genetic variants. By comparing the number of patients with gain‐of‐function mutations in PCSK9 with the number of familial hypercholesterolemia heterozygotes among subjects with hypercholesterolemia, the prevalence of subjects with gain‐of‐function mutations in PCSK9 in Norway can be estimated to one in 15 000.

Conclusion.  This study has provided novel information about the structural requirements for the normal function of PCSK9. However, more studies are needed to determine the mechanisms by which gain‐of‐function mutations in PCSK9 cause hypercholesterolemia.
Bird hosts, blood parasites and their vectors — associations uncovered by molecular analyses of blackfly blood meals
Authors: HELLGREN O. , BENSCH S. , MALMQVIST B.
Published: February 2008

The level of host specificity of blood‐sucking invertebrates may have both ecological and evolutionary implications for the parasites they are transmitting. We used blood meals from wild‐caught blackflies for molecular identification of parasites and hosts to examine patterns of host specificity and how these may affect the transmission of avian blood parasites of the genus Leucocytozoon. We found that five different species of ornithophilic blackflies preferred different species of birds when taking their blood meals. Of the blackflies that contained avian blood meals, 62% were infected with Leucocytozoon parasites, consisting of 15 different parasite lineages. For the blackfly species, there was a significant association between the host width (measured as the genetic differentiation between the used hosts) and the genetic similarity of the parasites in their blood meals. The absence of similar parasite in blood meals from blackflies with different host preferences is interpreted as a result of the vector–host associations. The observed associations between blackfly species and host species are therefore likely to hinder parasites to be transmitted between different host‐groups, resulting in ecologically driven associations between certain parasite lineages and hosts species.
Lactococcus lactis produces short‐chain quinones that cross‐feed Group B Streptococcus to activate respiration growth
Authors: Rezaïki Lahcen , Lamberet Gilles , Derré Aurélie , Gruss Alexandra , Gaudu Philippe
Published: February 2008

Quinones are essential components of the respiration chain that shuttle electrons between oxidoreductases. We characterized the quinones synthesized by Lactococcus lactis, a fermenting bacterium that activates aerobic respiration when a haem source is provided. Two distinct subgroups were characterized: Menaquinones (MK) MK‐8 to MK‐10, considered as hallmarks of L. lactis, are produced throughout growth. MK‐3 and demethylMK‐3 [(D)MK‐3] are newly identified and are present only late in growth. Production of (D)MK‐3 was conditional on the carbon sugar and on the presence of carbon catabolite regulator gene ccpA. Electron flux driven by both (D)MK fractions was shared between the quinol oxidase and extracellular acceptors O2, iron and, with remarkable efficiency, copper. Purified (D)MK‐3, but not MK‐8–10, complemented a menB defect in L. lactis. We previously showed that a respiratory metabolism is activated in Group B Streptococcus (GBS) by exogenous haem and MK, and that this activity is implicated in virulence. Here we show that growing lactococci donate (D)MK to GBS to activate respiration and stimulate growth of this opportunist pathogen. We propose that conditions favouring (D)MK production in dense microbial ecosystems, as present in the intestinal tract, could favour implantation of (D)MK‐scavengers like GBS within the complex.
Biosynthesis and IroC‐dependent export of the siderophore salmochelin are essential for virulence of Salmonella enterica serovar Typhimurium
Authors: Crouch Marie‐Laure V. , Castor Margaret , Karlinsey Joyce E. , Kalhorn Thomas , Fang Ferric C.
Published: February 2008

In response to iron deprivation, Salmonella enterica serovar Typhimurium secretes two catecholate‐type siderophores, enterobactin and its glucosylated derivative salmochelin. Although the systems responsible for enterobactin synthesis and acquisition are well characterized, the mechanisms of salmochelin secretion and acquisition, as well as its role in Salmonella virulence, are incompletely understood. Herein we show by liquid chromatography‐mass spectrometry analysis of culture supernatants from wild type and isogenic mutant bacterial strains that the Major Facilitator Superfamily pump EntS is the major exporter of enterobactin and the ABC transporter IroC exports both salmochelin and enterobactin. Growth promotion experiments demonstrate that IroC is not required for utilization of Fe‐enterobactin or Fe‐salmochelin, as had been previously suggested, but the ABC transporter protein FepD is required for utilization of both siderophores. Salmonella mutants deficient in salmochelin synthesis or secretion exhibit reduced virulence during systemic infection of mice.
Ypt32p and Mlc1p bind within the vesicle binding region of the class V myosin Myo2p globular tail domain
Authors: Casavola Elena Caroli , Catucci Alessandro , Bielli Pamela , Di Pentima Alessio , Porcu Giampiero , Pennestri Matteo , Cicero Daniel O. , Ragnini‐Wilson Antonella
Published: February 2008

Myosin V is an actin‐based motor essential for a variety of cellular processes including skin pigmentation, cell separation and synaptic transmission. Myosin V transports organelles, vesicles and mRNA by binding, directly or indirectly, to cargo‐bound receptors via its C‐terminal globular tail domain (GTD). We have used the budding yeast myosin V Myo2p to shed light on the mechanism of how Myo2p interacts with post‐Golgi carriers. We show that the Rab/Ypt protein Ypt32p, which associates with membranes of the trans‐Golgi network, secretory vesicles and endosomes and is related to the mammalian Rab11, interacts with the Myo2p GTD within a region previously identified as the ‘vesicle binding region’. Furthermore, we show that the essential myosin light chain 1 (Mlc1p), required for vesicle delivery at the mother‐bud neck during cytokinesis, binds to the Myo2p GTD in a region overlapping that of Ypt32p. Our data are consistent with a role of Ypt32p and Mlc1p in regulating the interaction of post‐Golgi carriers with Myo2p subdomain II.
Dissecting the components of quinine accumulation in Plasmodium falciparum
Authors: Sanchez Cecilia P. , Stein Wilfred D. , Lanzer Michael
Published: February 2008

Although quinine, the active ingredient of chinchona bark, has been used in the treatment of malaria for several centuries, there is little information regarding the interactions of this drug with the human malaria parasite Plasmodium falciparum. To better understand quinine's mode of action and the mechanism underpinning reduced responsiveness, we have investigated the factors that contribute to quinine accumulation by parasites that differ in their susceptibility to quinine. Interestingly, passive distribution, in accordance with the intracellular pH gradients, and intracellular binding could account for only a small fraction of the high amount of quinine accumulated by the parasites investigated. The results of trans‐stimulation kinetics suggest that high accumulation of quinine is brought about by a carrier‐mediated import system. This import system seems to be weakened in parasites with reduced quinine susceptibility. Other data show that polymorphisms within PfCRT are causatively linked with an increased verapamil‐sensitive quinine efflux that, depending on the genetic background, resulted in reduced quinine accumulation. The polymorphisms within PfMDR1 investigated did not affect quinine accumulation. Our data are consistent with the model that several factors, including acidotropic trapping, binding to intracellular sites and carrier‐mediated import and export transport systems, contribute to steady‐state intracellular quinine accumulation.
Regulation of quinone detoxification by the thiol stress sensing DUF24/MarR‐like repressor, YodB in Bacillus subtilis
Authors: Leelakriangsak Montira , Huyen Nguyen Thi Thu , Töwe Stefanie , Van Duy Nguyen , Becher Dörte , Hecker Michael , Antelmann Haike , Zuber Peter
Published: February 2008

Recently, we showed that the MarR‐type repressor YkvE (MhqR) regulates multiple dioxygenases/glyoxalases, oxidoreductases and the azoreductase encoding yvaB (azoR2) gene in response to thiol‐specific stress conditions, such as diamide, catechol and 2‐methylhydroquinone (MHQ). Here we report on the regulation of the yocJ (azoR1) gene encoding another azoreductase by the novel DUF24/MarR‐type repressor, YodB after exposure to thiol‐reactive compounds. DNA binding activity of YodB is directly inhibited by thiol‐reactive compounds in vitro. Mass spectrometry identified YodB‐Cys‐S‐adducts that are formed upon exposure of YodB to MHQ and catechol in vitro. This confirms that catechol and MHQ are auto‐oxidized to toxic ortho‐ and para‐benzoquinones which act like diamide as thiol‐reactive electrophiles. Mutational analyses further showed that the conserved Cys6 residue of YodB is required for optimal repression in vivo and in vitro while substitution of all three Cys residues of YodB affects induction of azoR1 transcription. Finally, phenotype analyses revealed that both azoreductases, AzoR1 and AzoR2 confer resistance to catechol, MHQ, 1,4‐benzoquinone and diamide. Thus, both azoreductases that are controlled by different regulatory mechanisms have common functions in quinone and azo‐compound reduction to protect cells against the thiol reactivity of electrophiles.
The divisomal protein DivIB contains multiple epitopes that mediate its recruitment to incipient division sites
Authors: Wadsworth Kimberly D. , Rowland Susan L. , Harry Elizabeth J. , King Glenn F.
Published: February 2008

Bacterial cytokinesis is orchestrated by an assembly of essential cell division proteins that form a supramolecular structure known as the divisome. DivIB and its orthologue FtsQ are essential members of the divisome in Gram‐positive and Gram‐negative bacteria respectively. DivIB is a bitopic membrane protein composed of an N‐terminal cytoplasmic domain, a single‐pass transmembrane domain, and a C‐terminal extracytoplasmic region comprised of three separate protein domains. A molecular dissection approach was used to determine which of these domains are essential for recruitment of DivIB to incipient division sites and for its cell division functions. We show that DivIB has three molecular epitopes that mediate its localization to division septa; two epitopes are encoded within the extracytoplasmic region while the third is located in the transmembrane domain. It is proposed that these epitopes represent sites of interaction with other divisomal proteins, and we have used this information to develop a model of the way in which DivIB and FtsQ are integrated into the divisome. Remarkably, two of the three DivIB localization epitopes are dispensable for vegetative cell division; this suggests that the divisome is assembled using a complex network of protein–protein interactions, many of which are redundant and likely to be individually non‐essential.
The Monitor project: rotation of low-mass stars in NGC 2362 – testing the disc regulation paradigm at 5 Myr
Authors: Irwin Jonathan , Hodgkin Simon , Aigrain Suzanne , Bouvier Jerome , Hebb Leslie , Irwin Mike , Moraux Estelle
Published: February 2008

We report on the results of a time-series photometric survey of NGC 2362, carried out using the CTIO 4-m Blanco telescope and Mosaic-II detector as part of the Monitor project. Rotation periods were derived for 271 candidate cluster members over the mass range 0.1 ≲M/M⊙≲ 1.2. The rotation period distributions show a clear mass-dependent morphology, qualitatively similar to that in NGC 2264, as would be expected from the age of this cluster. Using models of angular momentum evolution, we show that angular momentum losses over the ∼1–5 Myr age range appear to be needed in order to reproduce the evolution of the slowest rotators in the sample from the ONC to NGC 2362, as found by many previous studies. By incorporating Spitzer IRAC mid-infrared (mid-IR) measurements, we found that three to four objects showing mid-IR excesses indicative of the presence of circumstellar discs were all slow rotators, as would be expected in the disc regulation paradigm for early pre-main-sequence angular momentum evolution, but this result is not statistically significant at present, given the extremely limited sample size.
A comparison of ammonium, nitrate and proton net fluxes along seedling roots of Douglas‐fir and lodgepole pine grown and measured with different inorganic nitrogen sources
Authors: HAWKINS B. J. , BOUKCIM H. , PLASSARD C.
Published: February 2008

Significant spatial variability in NH4+, NO3− and H+ net fluxes was measured in roots of young seedlings of Douglas‐fir (Pseudotsuga menziesii) and lodgepole pine (Pinus contorta) with ion‐selective microelectrodes. Seedlings were grown with NH4+, NO3−, NH4NO3 or no nitrogen (N), and were measured in solutions containing one or both N ions, or no N in a full factorial design. Net NO3− and NH4+ uptake and H+ efflux were greater in Douglas‐fir than lodgepole pine and in roots not exposed to N in pretreatment. In general, the rates of net NH4+ uptake were the same in the presence or absence of NO3−, and vice versa. The highest NO3− influx occurred 0–30 mm from the root apex in Douglas‐fir and 0–10 mm from the apex in lodgepole pine. Net NH4+ flux was zero or negative (efflux) at Douglas‐fir root tips, and the highest NH4+ influx occurred 5–20 mm from the root tip. Lodgepole pine had some NH4+ influx at the root tips, and the maximum net uptake 5 mm from the root tip. Net H+ efflux was greatest in the first 10 mm of roots of both species. This study demonstrates that nutrient uptake by conifer roots can vary significantly across different regions of the root, and indicates that ion flux profiles along the roots may be influenced by rates of root growth and maturation.
Expression differences for genes involved in lignin, glutathione and sulphate metabolism in response to cadmium in Arabidopsis thaliana and the related Zn/Cd‐hyperaccumulator Thlaspi caerulescens
Authors: VAN DE MORTEL JUDITH E. , SCHAT HENK , MOERLAND PERRY D. , VAN THEMAAT EMIEL VER LOREN , VAN DER ENT SJOERD , BLANKESTIJN HETTY , GHANDILYAN ARTAK , TSIATSIANI STYLIANI , AARTS MARK G.M.
Published: February 2008

Cadmium (Cd) is a widespread, naturally occurring element present in soil, rock, water, plants and animals. Cd is a non‐essential element for plants and is toxic at higher concentrations. Transcript profiles of roots of Arabidopsis thaliana (Arabidopsis) and Thlaspi caerulescens plants exposed to Cd and zinc (Zn) are examined, with the main aim to determine the differences in gene expression between the Cd‐tolerant Zn‐hyperaccumulator T. caerulescens and the Cd‐sensitive non‐accumulator Arabidopsis. This comparative transcriptional analysis emphasized the role of genes involved in lignin, glutathione and sulphate metabolism. Furthermore the transcription factors MYB72 and bHLH100 were studied for their involvement in metal homeostasis, as they showed an altered expression after exposure to Cd. The Arabidopsis myb72 knockout mutant was more sensitive to excess Zn or iron (Fe) deficiency than wild type, while Arabidopsis transformants overexpressing bHLH100 showed increased tolerance to high Zn and nickel (Ni) compared to wild‐type plants, confirming their role in metal homeostasis in Arabidopsis.
Phosphatidylinositol 3‐ and 4‐phosphate modulate actin filament reorganization in guard cells of day flower
Authors: CHOI YUNJUNG , LEE YUREE , JEON BYEONG WOOK , STAIGER CHRISTOPHER J. , LEE YOUNGSOOK
Published: February 2008

Phosphatidylinositol 3‐kinases (PtdIns 3‐kinases) that produce phosphatidylinositol (3,4,5) triphosphate (PtdIns(3,4,5)P3) are considered to be important regulators of actin dynamics in animal cells. In plants, neither PtdIns(3,4,5)P3 nor the enzyme that produces this lipid has been reported. However, a PtdIns 3‐kinase that produces phosphatidylinositol 3‐phosphate (PtdIns3P) has been identified, suggesting that PtdIns3P, instead of PtdIns(3,4,5)P3, regulates actin dynamics in plant cells. Phosphatidylinositol 4‐kinase (PtdIns 4‐kinase) is closely associated with the actin cytoskeleton in plant cells, suggesting a role for this lipid kinase and its product phosphatidylinositol 4‐phosphate (PtdIns4P) in actin‐related processes. Here, we investigated whether or not PtdIns3P or PtdIns4P plays a role in actin reorganization induced by a plant hormone abscisic acid (ABA) in guard cells of day flower (Commelina communis). ABA‐induced changes in actin filaments were inhibited by LY294002 (LY) and wortmannin (WM), inhibitors of PtdIns3P and PtdIns4P synthesis. Expression of PtdIns3P‐ and PtdIns4P‐binding domains also inhibited ABA‐induced actin reorganization in a manner similar to LY and WM. These results suggest that PtdIns3P and PtdIns4P regulate actin dynamics in guard cells. Furthermore, we demonstrate that PtdIns3P exerts its effect on actin dynamics, at least in part, via generation of reactive oxygen species (ROS) in response to ABA.
Expression of an oxalate oxidase gene in tomato and severity of disease caused by Botrytis cinerea and Sclerotinia sclerotiorum
Authors: Walz A. , Zingen‐Sell I. , Loeffler M. , Sauer M.
Published: February 2008

A cDNA clone of wheat oxalate oxidase (OxO) under the control of the constitutive CAMV 35S promotor was expressed in tomato plants by Agrobacterium‐mediated transformation. Twenty‐six transgenic tomato lines were obtained and analysed. PCR experiments confirmed the incorporation of the OxO gene in all tested tomato lines. The transgenic tomato plants expressed a 124‐kDa protein showing OxO activity, and were able to convert different oxalic acid (OA) concentrations in vitro. In a detached leaf assay, most of the transgenic lines showed reduced disease symptoms compared with controls, following inoculation with Botrytis cinerea. In addition, leaves of the line T15 showed a marked reduction in symptoms compared with the control following inoculation with Sclerotinia sclerotiorum.
Suppression of clubroot disease under neutral pH caused by inhibition of spore germination of Plasmodiophora brassicae in the rhizosphere
Authors: Niwa R. , Nomura Y. , Osaki M. , Ezawa T.
Published: February 2008

To elucidate the mechanism of clubroot suppression under neutral soil pH, a highly reproducible germination assay system under soil culture conditions was designed based on the hypothesis that germinated spores of Plasmodiophora brassicae could be identified by the absence of a nucleus (i.e. having released a zoospore to infect a root hair of the host plant). Brassica rapa var. perviridis seedlings were inoculated with a spore suspension of P. brassicae at a rate of 2·0 × 106 spores g−1 soil and grown in a growth chamber for 7 days. The spores were recovered from rhizosphere and non‐rhizosphere soils and stained with both Fluorescent Brightener 28 (cell‐wall‐specific) and SYTO 82 orange fluorescent nucleic‐acid stain (nucleus‐specific stain). Total numbers of spores were counted under UV‐excitation, and spores with a nucleus that fluoresced orange under G‐excitation were counted. The significant increase in the percentage of spores without a nucleus (germinated spores) in the rhizosphere after 7 days’ cultivation and the correlation with root‐hair infections validated the assay system. Applications of calcium‐rich compost or calcium carbonate to neutralize the soil significantly reduced the percentage of germinated spores in the rhizosphere, as well as the number of root‐hair infections. The present study provides direct evidence that the inhibition of spore germination is the primary cause of disease suppression under neutral soil pH.
Proteasome Antibodies in Patients with Cancer or Multiple Sclerosis
Authors: Thuy‐Tien H. , Haugen M. , Aarseth J. , Storstein A. , Vedeler C. A.
Published: February 2008

Proteasome antibodies were detected by enzyme‐linked immunosorbent assay in two of the 45 (4.4%) patients with lung cancer, 0 of the 39 patients with breast cancer and six of the 51 (11.8%) patients with ovarian cancer. Six of the 47 (12.8%) patients with relapsing remitting multiple sclerosis had proteasome antibodies, as well as two of the 100 (2%) blood donors. Significant higher odds ratios compared to the blood donors were found for the patients with ovarian cancer (OR: 6.4; 95% CI: 1.1–68) and multiple sclerosis (OR: 7.1; 95% CI: 1.2–74). There was no association between proteasome antibodies and metastases or onconeural antibodies. The antibodies showed reactivity to 23, 25 and 27 kD proteins of the 20S proteasome using Western blot. The increased prevalence of proteasome antibodies in patients with ovarian cancer or multiple sclerosis may reflect cellular damage and release of intracellular antigens. Whether the antibodies take part in the clearance of released proteasomes and thus participate in the pathogenesis of cancer or autoimmune disease is not known.
Revision of the ‘nudidrosophila’ and ‘ateledrosophila’ species groups of Hawaiian Drosophila (Diptera: Drosophilidae), with descriptions of twenty‐two new species
Authors: MAGNACCA KARL N. , O’GRADY PATRICK M.
Published: February 2008

Abstract The ‘nudidrosophila’ and ‘ateledrosophila’ species groups, formerly described as genera, are a relatively small and understudied part of the enormous Hawaiian Drosophila radiation. Only nine species were described previously. Here we revise the two groups, provide a key to males and females, and describe fully all species. The ‘ateledrosophila’ group now contains three species, D. diamphidia Hardy, D. papala sp.n., and D. preapicula Hardy. The 28 species of the ‘nudidrosophila’ group are separated into five subgroups: ‘hirtitibia’ (D. hirtitibia Hardy, D. konaensis sp.n., D. mawaena sp.n., and D. papaalai sp.n.); ‘kahania’ (D. kahania sp.n. and D. longipalpus sp.n.); ‘nudidrosophila’ (D. aenicta Hardy, D. amita Hardy, D. canavalia sp.n., D. eximia Hardy, D. gemmula Hardy, D. kualapa sp.n., D. lepidobregma Hardy, D. mahui sp.n., D. malele sp.n., D. panoanoa sp.n., and D. poonia sp.n.); ‘okala’ (D. akoko sp.n., D. kuhao sp.n., D. makawao sp.n., D. okala sp.n., and D. panina sp.n.); and ‘velata’ (D. halapepe sp.n., D. kauaiensis sp.n., D. lauoho sp.n., D. milolii sp.n., D. pohaka sp.n., and D. velata Hardy).
Systematics and biogeography of the genusActenodia(Coleoptera: Meloidae: Mylabrini)
Authors: BOLOGNA MARCO A. , DI GIULIO ANDREA , PITZALIS MONICA
Published: February 2008

AbstractThe genusActenodiaLaporte de Castelnau (Meloidae: Mylabrini) is revised. It includes 18 species distributed in the Mediterranean and Saharo‐Arabian regions, and in eastern and southern Africa;A. carpanetoisp.n.from Mozambique is described. The bionomics of the genus is summarized, according to a collection of records on phenology, elevation, habitat preference and host plants. A classification of the genus is proposed after a morphological cladistic analysis: one Afrotropical lineage clearly emerged with three distinct groups of species, whereas other taxa, all Palaearctic exceptA. mirabilis, remained unresolved. The analysis of the nuclear internal transcribed spacer 2 rDNA sequences of some Palaearctic and Afrotropical species supports the distinction of the Afrotropical lineage. The first instar larvae of two species,A. chrysomelinafrom southern Africa andA. denticulatafrom Arabia, are described for the first time and compared with two other Palaearctic species described previously; inferences from larval morphology are discussed. The adult morphology of all species is described briefly and illustrated, and a key to the species is provided, as well as locality data. Three new synonymies are proposed:A. exteraDvořák, 1993syn.n.=A. septempunctataBaudi di Selve, 1878;A. sexpunctataPic, 1948syn.n. =A. curtulaFähraeus, 1870;A. unimaculata lanzaiKaszab, 1973syn.n. =A. unimaculataPic, 1908. The biogeography of the genus is discussed within the framework of a more general analysis of the disjunct distribution models.
Phylogenetic relationships of wild silkmoths (Lepidoptera: Saturniidae) inferred from four protein‐coding nuclear genes
Authors: REGIER JEROME C. , GRANT MICHAEL C. , MITTER CHARLES , COOK CHRISTOPHER P. , PEIGLER RICHARD S. , ROUGERIE RODOLPHE
Published: February 2008

Abstract The Saturniidae, or wild silkmoths, number approximately 1861 species in 162 genera and nine subfamilies including Cercophaninae and Oxyteninae. They include some of the largest and most spectacular of all Lepidoptera, such as the moon or luna moths, atlas moths, emperor moths, and many others. Saturniids have been important as sources of wild silk and/or human food in a number of cultures, and as models for comparative studies of genetics, development, physiology, and ecology. Seeking to improve the phylogenetic framework for such studies, we estimated relationships across Saturniidae, sampling all nine subfamilies plus all five tribes of Saturniinae. Seventy‐five exemplars (45 Saturniidae plus 30 bombycoid outgroups) were sequenced for four protein‐coding nuclear gene regions (5625 bp total), namely CAD (the fusion protein carbamoylphosphate synthetase/aspartate transcarbamylase/dihydroorotase), DDC (dopa decarboxylase), period, and wingless. The data, analyzed by parsimony and likelihood, gave a strongly resolved phylogeny at all levels. Relationships among subfamilies largely mirrored the pre‐cladistic hypothesis of Michener, albeit with significant exceptions, and there was definitive support for the morphology‐based proposal that Ludiinae form a tribe (Micragonini) within Saturniinae. In the latter subfamily, the African tribe Urotini was shown to be paraphyletic with respect to Bunaeini and Micragonini, also in accord with recent morphological findings. Relationships within the New World subfamilies Arsenurinae, Ceratocampinae and Hemileucinae nearly always accord with previous morphology‐based phylogenies when both are clearly resolved. Within Hemileucinae, Hemileucini are paraphyletic with respect to the monotypic Polythysanini. A preliminary biogeographical analysis supports ancestral restriction to the New World, followed by dispersal and/or vicariance splitting most of the family into a largely New World versus a largely Old World clade.
Cladistic analysis of Reduviidae (Heteroptera: Cimicomorpha) based on morphological characters
Authors: WEIRAUCH CHRISTIANE
Published: February 2008

AbstractWith more than 6600 species worldwide, Reduviidae (Insecta: Heteroptera), or assassin bugs, form the second largest and one of the most diverse groups of true bugs. The poor condition of the higher‐level classification of Reduviidae is reflected by the facts that different authors recognize between 21 and 32 subfamily‐level names and that Reduviidae were never subjected to a rigorous cladistic analysis using an exemplar approach. In the present study, a cladistic analysis of higher‐level taxa of Reduviidae based on 162 morphological characters and 75 ingroup and outgroup species is presented. Twenty‐one subfamily‐level taxa of Reduviidae were examined, accounting for 28 tribes. In addition to characters previously used for diagnosis in Reduviidae, information on recently published character complexes is used in the present analysis, supplemented with new character information gathered specifically for this project. Reduviidae are supported as a monophyletic group with Pachynomidae as their sister taxon. The major results of this study are the support of a sistergroup relationship of Hammacerinae with the remaining Reduviidae, the monophyly of the Phymatine Complex, the relatively basal position of Harpactorinae within Reduviidae as well as a novel hypothesis on the relationships within this group, and the sistergroup relationship of Ectrichodiinae + Tribelocephalinae and their placement in a clade that also contains Emesinae, Saicinae, and Visayanocorinae. The analysis further supports a clade formed by paraphyletic Salyavatinae + Sphaeridopinae, renders Vesciinae non‐monophyletic, and demonstrates the polyphyly of Reduviinae. Pseudocetherinae are shown to group with some Reduviinae. Triatominae are supported as a monophyletic group and are nested among additional Reduviinae and Stenopodainae.
Biochemical approaches for discovering protein–protein interactions
Authors: Miernyk Jan A. , Thelen Jay J.
Published: February 2008

Protein–protein interactions or protein complexes are integral in nearly all cellular processes, ranging from metabolism to structure. Elucidating both individual protein associations and complex protein interaction networks, while challenging, is an essential goal of functional genomics. For example, discovering interacting partners for a ‘protein of unknown function’ can provide insight into actual function far beyond what is possible with sequence‐based predictions, and provide a platform for future research. Synthetic genetic approaches such as two‐hybrid screening often reveal a perplexing array of potential interacting partners for any given target protein. It is now known, however, that this type of anonymous screening approach can yield high levels of false‐positive results, and therefore putative interactors must be confirmed by independent methods. In vitro biochemical strategies for identifying interacting proteins are varied and time‐honored, some being as old as the field of protein chemistry itself. Herein we discuss five biochemical approaches for isolating and characterizing protein–protein interactions in vitro: co‐immunoprecipitation, blue native gel electrophoresis, in vitro binding assays, protein cross‐linking, and rate‐zonal centrifugation. A perspective is provided for each method, and where appropriate specific, trial‐tested methods are included.
Identification of metabolic and biomass QTL in Arabidopsis thaliana in a parallel analysis of RIL and IL populations
Authors: Lisec Jan , Meyer Rhonda C. , Steinfath Matthias , Redestig Henning , Becher Martina , Witucka‐Wall Hanna , Fiehn Oliver , Törjék Ottó , Selbig Joachim , Altmann Thomas , Willmitzer Lothar
Published: February 2008

Plant growth and development are tightly linked to primary metabolism and are subject to natural variation. In order to obtain an insight into the genetic factors controlling biomass and primary metabolism and to determine their relationships, two Arabidopsis thaliana populations [429 recombinant inbred lines (RIL) and 97 introgression lines (IL), derived from accessions Col‐0 and C24] were analyzed with respect to biomass and metabolic composition using a mass spectrometry‐based metabolic profiling approach. Six and 157 quantitative trait loci (QTL) were identified for biomass and metabolic content, respectively. Two biomass QTL coincide with significantly more metabolic QTL (mQTL) than statistically expected, supporting the notion that the metabolic profile and biomass accumulation of a plant are linked. On the same basis, three out the six biomass QTL can be simulated purely on the basis of metabolic composition. QTL based on analysis of the introgression lines were in substantial agreement with the RIL‐based results: five of six biomass QTL and 55% of the mQTL found in the RIL population were also found in the IL population at a significance level of P ≤ 0.05, with >80% agreement on the allele effects. Some of the differences could be attributed to epistatic interactions. Depending on the search conditions, metabolic pathway‐derived candidate genes were found for 24–67% of all tested mQTL in the database AraCyc 3.5. This dataset thus provides a comprehensive basis for the detection of functionally relevant variation in known genes with metabolic function and for identification of genes with hitherto unknown roles in the control of metabolism.
A cysteine‐rich receptor‐like kinase NCRK and a pathogen‐induced protein kinase RBK1 are Rop GTPase interactors
Authors: Molendijk Arthur J. , Ruperti Benedetto , Singh Manoj K. , Dovzhenko Alexander , Ditengou Franck A. , Milia Mattia , Westphal Lore , Rosahl Sabine , Soellick Tim‐Robert , Uhrig Joachim , Weingarten Lars , Huber Michael , Palme Klaus
Published: February 2008

In plants, Rop/Rac GTPases have emerged as central regulators of diverse signalling pathways in plant growth and pathogen defence. When active, they interact with a wide range of downstream effectors. Using yeast two‐hybrid screening we have found three previously uncharacterized receptor‐like protein kinases to be Rop GTPase‐interacting molecules: a cysteine‐rich receptor kinase, named NCRK, and two receptor‐like cytosolic kinases from the Arabidopsis RLCK‐VIb family, named RBK1 and RBK2. Uniquely for Rho‐family small GTPases, plant Rop GTPases were found to interact directly with the protein kinase domains. Rop4 bound NCRK preferentially in the GTP‐bound conformation as determined by flow cytometric fluorescence resonance energy transfer measurements in insect cells. The kinase RBK1 did not phosphorylate Rop4 in vitro, suggesting that the protein kinases are targets for Rop signalling. Bimolecular fluorescence complementation assays demonstrated that Rop4 interacted in vivo with NCRK and RBK1 at the plant plasma membrane. In Arabidopsis protoplasts, NCRK was hyperphosphorylated and partially co‐localized with the small GTPase RabF2a in endosomes. Gene expression analysis indicated that the single‐copy NCRK gene was relatively upregulated in vasculature, especially in developing tracheary elements. The seven Arabidopsis RLCK‐VIb genes are ubiquitously expressed in plant development, and highly so in pollen, as in case of RBK2. We show that the developmental context of RBK1 gene expression is predominantly associated with vasculature and is also locally upregulated in leaves exposed to Phytophthora infestans and Botrytis cinerea pathogens. Our data indicate the existence of cross‐talk between Rop GTPases and specific receptor‐like kinases through direct molecular interaction.