bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimating the cost of protecting groundcover on privately managed properties in the Australian rangelands: the case of the West 2000 Plus Enterprise-Based Conservation scheme
Authors: Moss Jonathan , Sinden Jack , Stayner Richard
Published: February 2012

A significant quantity of native vegetation and biodiversity remains on privately managed rangeland properties. Due to a lack of appropriate incentives, landholders do not always conserve these resources at a level that society desires. Regulations to conserve native vegetation can impose substantial costs on landholders. Market-Based Instruments have therefore been developed to provide market incentives aimed at achieving conservation at lower costs. We review the application of a Market-Based Instrument scheme, the West 2000 Plus Enterprise-Based Conservation program, which was designed for the Western Division of New South Wales. We estimate the private and social costs of increasing groundcover on privately managed properties, with and without the scheme. The costs are estimated under actual market and climatic conditions, and simulated under a wider range of conditions. The results indicate that costs vary widely across different conservation areas, depending on the location and previous management strategies of the property. The Enterprise-Based Conservation scheme has increased conservation in the region, and the implications from its application are reviewed to assist the further development of Market-Based Instruments.
Disruption of ATP-binding cassette B8 in mice leads to cardiomyopathy through a decrease in mitochondrial iron export
Authors: Ichikawa Yoshihiko , Bayeva Marina , Ghanefar Mohsen , Potini Vishnu , Sun Lin , Mutharasan R. Kannan , Wu Rongxue , Khechaduri Arineh , Jairaj Naik Tejaswitha , Ardehali Hossein
Published: February 2012

Mitochondrial iron levels are tightly regulated, as iron is essential for the synthesis of Fe/S clusters and heme in the mitochondria, but high levels can cause oxidative stress. The ATP-binding cassette (ABC) transporter ABCB8 is a mitochondrial inner membrane protein with an unknown function. Here, we show that ABCB8 is involved in mitochondrial iron export and is essential for baseline cardiac function. Induced genetic deletion of ABCB8 in mouse hearts resulted in mitochondrial iron accumulation and cardiomyopathy, as assessed by echocardiography and invasive hemodynamics. Mice with ABCB8 deletion in the heart also displayed mitochondrial damage, and higher levels of reactive oxygen species and cell death. Down-regulation of ABCB8 in vitro resulted in decreased iron export from isolated mitochondria, whereas its overexpression had the opposite effect. Furthermore, ABCB8 is needed for the maturation of the cytosolic Fe/S proteins, as its deletion in vitro and in vivo led to decreased activity of cytosolic, but not mitochondrial, iron–sulfur-containing enzymes. These results indicate that ABCB8 is essential for normal cardiac function, maintenance of mitochondrial iron homeostasis and maturation of cytosolic Fe/S proteins. In summary, this report provides characterization of a protein involved in mitochondrial iron export.
First Report of Bipolaris peregianensis Causing Leaf Spot of Cynodon dactylon in China
Authors: Wang Z. Y. , Xie S. N. , Wang Y. , Wu H. Y. , Zhang M.
Published: February 2012

Cynodon dactylon is widely cultivated as a sod crop in warm climates worldwide. In early September 2009, heavy leaf spot infection was observed on C. dactylon from Zhengzhou, Henan, China. Early symptoms appeared as small, elliptical, pale brown lesions on the leaves. Lesions later expanded to 5 to 10 mm long and 1 to 2 mm wide, becoming brown to dark brown. A fungus was consistently isolated from leaf spots on potato dextrose agar (PDA), but with poor sporulation. Morphological characteristics were observed from single-conidium cultures on tap water agar + wheat straw (TWA+W) after 5 to 7 days. Conidiophores were light to medium brown, cylindrical, solitary or clustered, unbranched, usually with basal cells enlarged, and 94.5 to 147.0 × 4.0 to 9.0 μm. Conidia were fusoid, strongly curved, end cells broadly hemiellipsoidal, brown, 58.5 to 84.5 × 13.5 to 18.5 μm, with 6 to 10 septa. These morphological characteristics are similar to those of Bipolaris peregianensis (2). The identity of our fungus was confirmed to be B. peregianensis by DNA sequencing of the internal transcribed spacer (ITS) region (GenBank Accession No. JQ316121), which was 99% homologous to those of other B. peregianensis isolates (= Cochliobolus peregianensis; Accession Nos AF071328 and AF158111) (1). Koch's postulates were performed with the leaves of three pots of C. dactylon. Leaves were sprayed with 1 × 105 conidia/ml of B. peregianensis; an equal number of leaves in the pots of the same plant sprayed with sterile distilled water served as the control. All test plants were covered with plastic bags for 24 h to maintain high relative humidity at 23 to 25°C. After 7 days, more than 50% of inoculated leaves showed symptoms identical to those observed in natural condition, whereas controls remained symptom free. Reisolation of the fungus from lesions on inoculated leaves confirmed that the causal agent was B. peregianensis. To our knowledge, this is the first report of leaf spots caused by B. peregianensis on C. dactylon in China. The disease cycle and the control strategies in the regions are being further studied.

References: (1) M. L. Berbee et al. Mycologia 91:964, 1999. (2) A. Sivanesan. Mycol. Pap. 158:1, 1987.
Habitat stability affects dispersal and the ability to track climate change
Authors: Hof Christian , Brändle Martin , Dehling D. Matthias , Munguía Mariana , Brandl Roland , Araújo Miguel B. , Rahbek Carsten
Published: February 2012

Habitat persistence should influence dispersal ability, selecting for stronger dispersal in habitats of lower temporal stability. As standing (lentic) freshwater habitats are on average less persistent over time than running (lotic) habitats, lentic species should show higher dispersal abilities than lotic species. Assuming that climate is an important determinant of species distributions, we hypothesize that lentic species should have distributions that are closer to equilibrium with current climate, and should more rapidly track climatic changes. We tested these hypotheses using datasets from 1988 and 2006 containing all European dragon- and damselfly species. Bioclimatic envelope models showed that lentic species were closer to climatic equilibrium than lotic species. Furthermore, the models over-predicted lotic species ranges more strongly than lentic species ranges, indicating that lentic species track climatic changes more rapidly than lotic species. These results are consistent with the proposed hypothesis that habitat persistence affects the evolution of dispersal.
Laguerre population processes
Authors: Jakeman E. , Hopcraft K. I.
Published: February 2012

We analyse a number of stochastic processes that give rise to first-order number statistics governed by Laguerre distributions with properties that lie between Poisson and geometric random variables. These distributions have hitherto been used to characterize the photon statistics of a coherent mixture of thermal and laser light. Here, we explore a number of discrete population processes that can lead to the same first-order statistics and correlation functions and highlight the distinguishing features that may be used to identify the relevant model from data.
Tin-containing silicates: structure–activity relations
Authors: Osmundsen Christian M. , Holm Martin Spangsberg , Dahl Søren , Taarning Esben
Published: February 2012

The selective conversion of biomass-derived substrates is one of the major challenges facing the chemical industry. Recently, stannosilicates have been employed as highly active and selective Lewis acid catalysts for a number of industrially relevant reactions. In the present work, four different stannosilicates have been investigated: Sn-BEA, Sn-MFI, Sn-MCM-41 and Sn-SBA-15. When comparing the properties of tin sites in the structures, substantial differences are observed. Sn-beta displays the highest Lewis acid strength, as measured by probe molecule studies using infrared spectroscopy, which gives it a significantly higher activity at low temperatures than the other structures investigated. Furthermore, the increased acid strength translates into large differences in selectivity between the catalysts, thus demonstrating the influence of the structure on the active site, and pointing the way forward for tailoring the active site to the desired reaction.
Chemokine C‐C motif receptor 5 and C‐C motif ligand 5 promote cancer cell migration under hypoxia
Authors: Lin Sensen , Wan Shuying , Sun Li , Hu Jialiang , Fang Dongdong , Zhao Renping , Yuan Shengtao , Zhang Luyong
Published: March 2012

The chemokine CC motif receptor 5 (CCR5) and its ligands have been reported to be associated with cancer progression and metastasis. Although recent researches have demonstrated a fundamental role of hypoxia in cancer, the effect of hypoxia on the expression and function of CCR5 and its ligands in cancer cells is unknown. Here, we investigated the status of CCR5 and its ligands in cancer cells under hypoxic conditions. Quantitative polymerase chain reaction, western blotting and immunofluorescence staining showed that hypoxia induced a strong increase of CCR5 expression. Dual luciferase assay and mRNA stability analysis indicated that hypoxia‐induced CCR5 mRNA expression relied on both transcriptional and posttranscriptional mechanisms. We detected the expression of CCR5 ligands and found that chemokine CC motif ligand 5 (CCL5) was induced under hypoxia. Recombinant human CCL5 stimulated cell migration rather than cell proliferation under hypoxia, and neutralization of CCL5 inhibited hypoxia‐induced migration of cancer cells. Similarly, overexpression of CCR5 increased cell migration, and knockdown of CCR5 attenuated hypoxia‐mediated cell migration. We further showed that hypoxia‐inducible factor‐1α (HIF‐1α) was involved in CCR5 and CCL5 regulation under hypoxia. HIF‐1α mRNA levels were highly correlated with CCR5 mRNA and CCL5 mRNA levels in clinical samples. CCR5 and CCL5 were highly expressed in breast cancer lymph nodes metastases. Taken together, our data suggest that CCR5‐CCL5 interaction promotes cancer cell migration under hypoxia. (Cancer Sci 2012; 103: 904–912)
Prostacyclin receptor in tumor endothelial cells promotes angiogenesis in an autocrine manner
Authors: Osawa Takahiro , Ohga Noritaka , Hida Yasuhiro , Kitayama Kazuko , Akiyama Kosuke , Onodera Yuichiro , Fujie Manabu , Shinohara Nobuo , Shindoh Masanobu , Nonomura Katsuya , Hida Kyoko
Published: March 2012

Molecules highly expressed in tumor endothelial cells (TEC) are important for specific targeting of these cells. Previously, using DNA microarray analysis, we found that the prostacyclin receptor (IP receptor) gene was upregulated in TEC compared with normal endothelial cells (NEC). Although prostacyclin is implicated in re‐endothelialization and angiogenesis, its role remains largely unknown in TEC. Moreover, the effect of the IP receptor on TEC has not been reported. In the present study we investigated the function of the IP receptor in TEC. The TEC were isolated from two types of human tumor xenografts in nude mice, while NEC were isolated from normal counterparts. Prostacyclin secretion levels in TEC were significantly higher than those in NEC, as shown using ELISA. Real‐time RT‐PCR showed that the IP receptor was upregulated in TEC compared with NEC. Furthermore, migration and tube formation of TEC were suppressed by the IP receptor antagonist RO1138452. Immunohistostaining showed that the IP receptor was specifically expressed in blood vessels of renal cell carcinoma specimens, but not in glomerular vessels of normal renal tissue. These findings suggest that the IP receptor is a TEC‐specific marker and might be a useful therapeutic target. (Cancer Sci 2012; 103: 1038–1044)
Regulation of the metabolite profile by an APC gene mutation in colorectal cancer
Authors: Yoshie Tomoo , Nishiumi Shin , Izumi Yoshihiro , Sakai Aya , Inoue Jun , Azuma Takeshi , Yoshida Masaru
Published: March 2012

Mutation of the APC gene occurs during the early stages of colorectal cancer development. To obtain new insights into the mechanisms underlying the aberrant activation of the Wnt pathway that accompanies APC mutation, we carried out a gas chromatography–mass spectrometry‐based semiquantitative metabolome analysis. In vitro experiments comparing SW480 cells expressing normal APC and truncated APC indicated that the levels of metabolites involved in the latter stages of the intracellular tricarboxylic acid cycle, including succinic acid, fumaric acid, and malic acid, were significantly higher in the SW480 cells expressing the truncated APC. In an in vivo study, we found that the levels of most amino acids were higher in the non‐polyp tissues of APCmin/+ mice than in the normal tissues of the control mice and the polyp tissues of APCmin/+ mice. Ribitol, the levels of which were decreased in the polyp lesions of the APCmin/+ mice and the SW480 cells expressing the truncated APC, reduced the growth of SW480 cells with the APC mutation, but did not affect the growth of SW480 transfectants expressing full‐length APC. The level of sarcosine was found to be significantly higher in the polyp tissues of APCmin/+ mice than in their non‐polyp tissues and the normal tissues of the control mice, and the treatment of SW480 cells with 50 μM sarcosine resulted in a significant increase in their growth rate. These findings suggest that APC mutation causes changes in energetic metabolite pathways and that these alterations might be involved in the development of colorectal cancer. (Cancer Sci 2012; 103: 1010–1021)
Area and the rapid radiation of HawaiianBidens(Asteraceae)
Authors: Knope Matthew L. , Morden Clifford W. , Funk Vicki A. , Fukami Tadashi
Published: March 2012

Aim To estimate the rate of adaptive radiation of endemic HawaiianBidensand to compare their diversification rates with those of other plants in Hawaii and elsewhere with rapid rates of radiation.

Location Hawaii.

Methods Fifty‐nine samples representing all 19 Hawaiian species, six Hawaiian subspecies, two Hawaiian hybrids and an additional two Central American and two AfricanBidensspecies had their DNA extracted, amplified by polymerase chain reaction and sequenced for four chloroplast and two nuclear loci, resulting in a total of approximately 5400 base pairs per individual. Internal transcribed spacer sequences for additional outgroup taxa, including 13 non‐HawaiianBidens, were obtained from GenBank. Phylogenetic relationships were assessed by maximum likelihood and Bayesian inference. The age of the most recent common ancestor and diversification rates of HawaiianBidenswere estimated using the methods of previously published studies to allow for direct comparison with other studies. Calculations were made on a per‐unit‐area basis.

Results We estimate the age of the Hawaiian clade to be 1.3–3.1 million years old, with an estimated diversification rate of 0.3–2.3 species/million years and 4.8 × 10−5to 1.3 × 10−4 species Myr−1 km−2.Bidensspecies are found in Europe, Africa, Asia and North and South America, but the Hawaiian species have greater diversity of growth form, floral morphology, dispersal mode and habitat type than observed in the rest of the genus world‐wide. Despite this diversity, we found little genetic differentiation among the Hawaiian species. This is similar to the results from other molecular studies on Hawaiian plant taxa, including others with great morphological variability (e.g. silverswords, lobeliads and mints).

Main conclusions On a per‐unit‐area basis, HawaiianBidenshave among the highest rates of speciation for plant radiations documented to date. The rapid diversification within such a small area was probably facilitated by the habitat diversity of the Hawaiian Islands and the adaptive loss of dispersal potential. Our findings point to the need to consider the spatial context of diversification – specifically, the relative scale of habitable area, environmental heterogeneity and dispersal ability – to understand the rate and extent of adaptive radiation.
Evidence for a Role of Endogenous Nesfatin‐1 in the Control of Water Drinking
Authors: Yosten G. L. C. , Redlinger L. , Samson W. K.
Published: February 2012

Nesfatin‐1, a post‐translational product of the nucleobindin‐2 (NucB2) gene, is produced in several brain areas known to be important in neuroendocrine, autonomic and metabolic function, including the hypothalamus and medulla. The hallmark action of the peptide is its ability at picomole doses to inhibit food and water intake in rodents and, indeed, the effect on water intake is more pronounced than that on food intake. In preliminary studies, we observed a decrease in hypothalamic NucB2 expression in response to overnight water deprivation even when food was present, which reversed when water was returned to the animals. We therefore hypothesised that the effect of nesfatin‐1 on water drinking was independent of its anorexigenic action. Indeed, rats administered nesfatin‐1 i.c.v. consumed significantly less water than controls in response to a subsequent, dipsogenic dose of angiotensin II, or upon return of water bottles after 18 h of fluid restriction (food present), or in response to a hypertonic challenge. Pretreatment with an antisense oligonucleotide against nesfatin‐1 significantly reduced levels of immunoreactive nesfatin‐1 in the hypothalamic paraventricular nucleus and resulted in exaggerated drinking responses to angiotensin II. The results obtained in the present study suggest that locally produced nesfatin‐1 may be an important component of the hypothalamic mechanisms controlling fluid and electrolyte homeostasis.
Maternal Deprivation in Rats is Associated with Corticotrophin‐Releasing Hormone (CRH) Promoter Hypomethylation and Enhances CRH Transcriptional Responses to Stress in Adulthood
Authors: Chen J. , Evans A. N. , Liu Y. , Honda M. , Saavedra J. M. , Aguilera G.
Published: February 2012

Exposure to stress during early development causes long‐lasting alterations in behaviour and hypothalamic pituitary adrenal (HPA) axis activity, including increased expression of corticotrophin‐releasing hormone (CRH). To determine whether early‐life stress causes epigenetic changes in the CRH promoter leading to increased CRH transcription, 8‐week old female and male rats, subjected to maternal deprivation (MD) between days 2 and 13 post‐birth, were studied for HPA axis responses to stress and CRH promoter methylation in the hypothalamic paraventricular nucleus (PVN) and central nucleus of the amygdala (CeA). Plasma corticosterone and PVN CRH heteronuclear (hn)RNA responses to acute restraint stress were higher in MD rats of both sexes. DNA methylation analysis of the CRH promoter revealed a significantly lower percentage of methylation in two CpGs preceding (CpG1) and inside (CpG2) the cyclic AMP‐response element (CRE) at −230 bp in the CRH promoter in the PVN but not the CeA of MD rats. Gel‐shift assays, using nuclear proteins from forskolin‐treated hypothalamic 4B cells and CRH promoter CRE oligonucleotides, unmethylated or methylated at CpG1, revealed a strong band that was supershifted by phospho‐cAMP response element‐binding antibody. This band was 50% weaker using oligonucleotides methylated at CpG2 (intra‐CRE), or methylated at both CpG1 and CpG2. These findings demonstrate that HPA axis hypersensitivity caused by neonatal stress causes long‐lasting enhanced CRH transcriptional activity in the PVN of both sexes. Hypomethylation of the CRH promoter CRE, a region critical for CRH transcriptional activation, could serve as a mechanism for the increased transcriptional responses to stress observed in MD rats.
Sucrose induces rapid activation of CfSAPK, a mitogen‐activated protein kinase, in Cephalostachyum fuchsianum Gamble cells
Authors: LI LUBIN , LI YUAN , ZHANG LU , XU CHUNHUI , SU TONGBING , REN DONGTAO , YANG HAILIAN
Published: February 2012

Sucrose was recently demonstrated to function as a molecular signal. However, sucrose‐specific sensing and signalling pathways remain largely undefined. Here, we show that Cephalostachyum fuchsianum sucrose‐activated protein kinase (CfSAPK) is transiently and specifically activated by sucrose in C. fuchsianum Gamble suspension cells. The result suggested that CfSAPK participates in a sucrose‐signalling pathway. CfSAPK was partially purified from sucrose‐treated cells and further analysed. Kinase activity assays revealed that CfSAPK preferentially used myelin basic protein (MBP) as substrate in vitro and strongly phosphorylate MBP threonine residue(s) and weakly phosphorylated MBP serine residue(s). Of the divalent cations tested, Mg2+ was required for CfSAPK activation. Phosphatase treatment of CfSAPK abolished its kinase activity, indicating that phosphorylation is required for CfSAPK activation. Seven internal tryptic peptides identified from CfSAPK matched mitogen‐activated protein kinases (MAPKs) in plants. CfSAPK cDNA was cloned using RT‐PCR and rapid amplification of cDNA ends (RACE). CfSAPK cDNA encodes a 382‐amino acid protein with a calculated molecular mass of 43 466.9 Da. The CfSAPK protein contains all 11 conserved kinase subdomains found in other Ser/Thr kinases. The amino acids sequence of CfSAPK is highly homologous to group A MAPKs in monocotyledon plants.
Facies architecture of individual basin‐plain turbidites: Comparison with existing models and implications for flow processes
Authors: SUMNER ESTHER J. , TALLING PETER J. , AMY LAWRENCE A. , WYNN RUSSELL B. , STEVENSON CHRISTOPHER J. , FRENZ MICHAEL
Published: March 2012

Current understanding of submarine sediment density flows is based heavily on their deposits, because such flows are notoriously difficult to monitor directly. However, it is rarely possible to trace the facies architecture of individual deposits over significant distances. Instead, bed‐scale facies models that infer the architecture of ‘typical’ deposits encapsulate current understanding of depositional processes and flow evolution. In this study, the distribution of facies in 12 individual beds has been documented along downstream transects over distances in excess of 100 km. These deposits were emplaced in relatively flat basin‐plain settings in the Miocene Marnoso Arenacea Formation, north‐east Italy and the late Quaternary Agadir Basin, offshore Morocco. Statistical analysis shows that the most common series of vertical facies transitions broadly resembles established facies models. However, mapping of individual beds shows that they commonly deviate from generalized models in several important ways that include: (i) the abundance of parallel laminated sand, suggesting deposition of this facies from both high‐density and low‐density turbidity current; (ii) three distinctly different types of grain‐size break, suggesting waxing flow, erosional hiatuses and bypass of silty sediment; (iii) the presence of mud‐rich debrites demonstrating hybrid flow deposition; and (iv) dune‐scale cross‐lamination in fine‐medium grained sandstones. Submarine sediment density flows in basin‐plain settings flow over relatively simple topography. Yet, their deposits record complex flow events, involving transformation between different flow types, rather than the simple waning surges often associated with the distal parts of turbidite systems.
TCP transcription factors interact with AS2 in the repression of class‐I KNOX genes in Arabidopsis thaliana
Authors: Li Ziyu , Li Bin , Shen Wen‐Hui , Huang Hai , Dong Aiwu
Published: March 2012

Leaf organogenesis occurs within the peripheral zone of the shoot apical meristem (SAM). The initiation and subsequent development of a leaf requires the stable repression of a highly conserved class of plant genes, namely class‐I KNOTTED 1‐like homeobox (KNOX) genes. In Arabidopsis, this class comprises four members: SHOOT MERISTEMLESS (STM); BREVIPEDICELLUS (BP); KNAT2 and KNAT6. Two transcription factors, ASYMMETRIC LEAVES 1 (AS1) and AS2, are known to form a protein complex to repress BP, KNAT2 and KNAT6. Here, we show that AS2 physically interacts with the microRNA319 (miR319)‐regulated CINCINNATA‐like TEOSINTE BRANCHED 1‐CYCLOIDEA‐PCF (TCP) transcription factors in vitro and in vivo. By chromatin immunoprecipitation, we demonstrated that AS2 and TCPs bind to similar regions of the BP and KNAT2 promoters. In addition, DNA‐binding activities of the TCP proteins rely on the presence of AS2, as the activities were dramatically reduced in the as2 mutant. The jaw‐D mutant, which overexpresses MIR319a to downregulate several target TCP genes, strongly enhanced the as2 phenotypes and caused more severe ectopic expression of BP, KNAT2 and KNAT6. Our results reveal that KNOX repression requires different types of transcription factors that function together to ensure normal leaf development.
Targeted disruption of an orthologue of DOMAINS REARRANGED METHYLASE 2, OsDRM2, impairs the growth of rice plants by abnormal DNA methylation
Authors: Moritoh Satoru , Eun Chang‐Ho , Ono Akemi , Asao Hisayo , Okano Yosuke , Yamaguchi Katsushi , Shimatani Zenpei , Koizumi Amane , Terada Rie
Published: March 2012

Recent methylome analyses of the entire Arabidopsis thaliana genome using various mutants have provided detailed information about the DNA methylation pattern and its function. However, information about DNA methylation in other plants is limited, partly because of the lack of mutants. To study DNA methylation in rice (Oryza sativa) we applied homologous recombination‐mediated gene targeting to generate targeted disruptants of OsDRM2, a rice orthologue of DOMAINS REARRANGED METHYLASE 1 and 2 (DRM1/2), which encode DNA methyltransferases responsible for de novo and non‐CG methylation in Arabidopsis. Whereas Arabidopsis drm1 drm2 double mutants showed no morphological alterations, targeted disruptants of rice OsDRM2 displayed pleiotropic developmental phenotypes in both vegetative and reproductive stages, including growth defects, semi‐dwarfed stature, reductions in tiller number, delayed heading or no heading, abnormal panicle and spikelet morphology, and complete sterility. In these osdrm2 disruptants, a 13.9% decrease in 5‐methylcytosine was observed by HPLC analysis. The CG and non‐CG methylation levels were reduced in RIRE7/CRR1 retrotransposons, and in 5S rDNA repeats. Associated transcriptional activation was detected in RIRE7/CRR1. Furthermore, de novo methylation by an RNA‐directed DNA methylation (RdDM) process involving transgene‐derived exogenous small interfering RNA (siRNA) was deficient in osdrm2‐disrupted cells. Impaired growth and abnormal DNA methylation of osdrm2 disruptants were restored by the complementation of wild‐type OsDRM2 cDNA. Our results suggest that OsDRM2 is responsible for de novo, CG and non‐CG methylation in rice genomic sequences, and that DNA methylation regulated by OsDRM2 is essential for proper rice development in both vegetative and reproductive stages.
Functional characterization of ObgC in ribosome biogenesis during chloroplast development
Authors: Bang Woo Young , Chen Ji , Jeong In Sil , Kim Sam Woong , Kim Chul Wook , Jung Hyun Suk , Lee Kyoung Hwan , Kweon Hee‐Seok , Yoko Ishizaki , Shiina Takashi , Bahk Jeong Dong
Published: March 2012

The Spo0B‐associated GTP‐binding protein (Obg) GTPase, essential for bacterial viability, is also conserved in eukaryotes, but its primary role in eukaryotes remains unknown. Here, our functional characterization of Arabidopsis and rice obgc mutants strongly underlines the evolutionarily conserved role of eukaryotic Obgs in organellar ribosome biogenesis. The mutants exhibited a chlorotic phenotype, caused by retarded chloroplast development. A plastid DNA macroarray revealed a plastid‐encoded RNA polymerase (PEP) deficiency in an obgc mutant, caused by incompleteness of the PEP complex, as its western blot exhibited reduced levels of RpoA protein, a component of PEP. Plastid rRNA profiling indicated that plastid rRNA processing is defective in obgc mutants, probably resulting in impaired ribosome biogenesis and, in turn, in reduced levels of RpoA protein. RNA co‐immunoprecipitation revealed that ObgC specifically co‐precipitates with 23S rRNA in vivo. These findings indicate that ObgC functions primarily in plastid ribosome biogenesis during chloroplast development. Furthermore, complementation analysis can provide new insights into the functional modes of three ObgC domains, including the Obg fold, G domain and OCT.
HDA19 is required for the repression of salicylic acid biosynthesis and salicylic acid‐mediated defense responses in Arabidopsis
Authors: Choi Sun‐Mee , Song Hae‐Ryong , Han Soon‐Ki , Han Muho , Kim Chi‐Yeol , Park Jaejin , Lee Yong‐Hwan , Jeon Jong‐Seong , Noh Yoo‐Sun , Noh Bosl
Published: March 2012

To cope with a lifetime of exposure to a variety of pathogens, plants have developed exquisite and refined defense mechanisms that vary depending on the type of attacking pathogen. Defense‐associated transcriptional reprogramming is a central part of plant defense mechanisms. Chromatin modification has recently been shown to be another layer of regulation for plant defense mechanisms. Here, we show that the RPD3/HDA1‐class histone deacetylase HDA19 is involved in the repression of salicylic acid (SA)‐mediated defense responses in Arabidopsis. Loss of HDA19 activity increased SA content and increased the expression of a group of genes required for accumulation of SA as well as pathogenesis related (PR) genes, resulting in enhanced resistance to Pseudomonas syringae. We found that HDA19 directly associates with and deacetylates histones at the PR1 and PR2 promoters. Thus, our study shows that HDA19, by modifying chromatin to a repressive state, ensures low basal expression of defense genes, such as PR1, under unchallenged conditions, as well as their proper induction without overstimulation during defense responses to pathogen attacks. Thus, the role of HDA19 might be critical in preventing unnecessary activation and self‐destructive overstimulation of defense responses, allowing successful growth and development.
The Arabidopsis SYN3 cohesin protein is important for early meiotic events
Authors: Yuan Li , Yang Xiaohui , Ellis Jessie L. , Fisher Nicole M. , Makaroff Christopher A.
Published: March 2012

α‐Kleisins are core components of meiotic and mitotic cohesin complexes. Arabidopsis contains four genes that encode α‐kleisin proteins: SYN1, SYN2, SYN3 and SYN4. SYN1, a REC8 ortholog, is essential for meiosis, while SYN2 and SYN4 appear to be SCC1 orthologs and function in mitosis. SYN3 is essential for megagametogenesis and is enriched in the nucleolus of meiotic and mitotic cells. In this study the role of SYN3 during meiosis was investigated by characterization of plants that express SYN3‐RNAi constructs from either meiotic DMC1, native SYN3, or inducible PX7 promoters. Reduction of SYN3 caused defects in homologous chromosome synapsis and synaptonemal complex (SC) formation during male and female meiosis. Consistent with this observation, relatively little signal for the SC component ZYP1 was detected on the chromosomes of SYN3‐RNAi plants. ZYP1 transcript levels were relatively normal, but several transcripts for genes that encode proteins involved in meiotic recombination were altered, which suggested that a reduction in SYN3 may inhibit meiotic progression by alteration of meiotic gene expression.
An improved method and data analysis for ultrasound acoustic emissions and xylem vulnerability in conifer wood
Authors: Wolkerstorfer Silviya V. , Rosner Sabine , Hietz Peter
Published: March 2012

The vulnerability of the xylem to cavitation is an important trait in plant drought resistance and has been quantified by several methods. We present a modified method for the simultaneous measurement of cavitations, recorded as ultrasound acoustic emissions (UAEs), and the water potential, measured with a thermocouple psychrometer, in small samples of conifer wood. Analyzing the amplitude of the individual signals showed that a first phase, during which the mean amplitude increased, was followed by a second phase with distinctly lower signal amplitudes. We provide a method to separate the two groups of signals and show that for many samples plausible vulnerability curves require rejecting late low‐energy UAEs. These very likely do not result from cavitations. This method was used to analyze the differences between juvenile wood, and early and late mature wood in Picea abies (L.) Karst. Juvenile earlywood was more resistant to cavitation than mature earlywood or latewood, which we relate to the tracheid anatomy of the samples.
DNA methylation and genome rearrangement characteristics of phase change in cultured shoots of Sequoia sempervirens
Authors: Huang Li‐Chun , Hsiao Lin‐June , Pu Szu‐Yuan , Kuo Ching‐I , Huang Bau‐Lian , Tseng Tsung‐Che , Huang Hao‐Jen , Chen Yu‐Ting
Published: March 2012

Epigenetic machinery regulates the expression of individual genes and plays a crucial role in globally shaping and maintaining developmental patterning. We studied the extent of DNA methylation in the nucleus, mitochondrion and chloroplast in cultured Sequoia sempervirens (coast redwood) adult, juvenile and rejuvenated shoots by measuring the ratio of methylcytosine to total cytosine using high‐performance liquid chromatography (HPLC). We also analyzed nuclear DNA (nuDNA) polymorphisms of different shoot types by methylation‐sensitive amplified fragment length polymorphism (MSAP) and Southern blot analysis. The extent of nuDNA methylation was greater in the adult vegetative than juvenile and rejuvenated shoots (8% vs 6.5–7.5%). In contrast, the proportion of methylcytosine was higher in mitochondrial DNA (mDNA) of juvenile and rejuvenated shoots than adult shoots (6.6% vs 7.8–8.2%). MSAP and Southern blot analyses identified three MSAP fragments which could be applied as phase‐specific molecular markers. We also found nuclear genome and mtDNA rearrangement may be as important as DNA methylation status during the phase change. Our findings strongly suggest that DNA methylation and genome rearrangement may affect the dynamic tissue‐ and cell type‐specific changes that determine the developmental phase of S. sempervirens shoots.
Phototropism and gravitropism in transgenic lines of Arabidopsis altered in the phytochrome pathway
Authors: Hopkins Jane A. , Kiss John Z.
Published: March 2012

Phytochromes are a family of photoreceptor molecules, absorbing primarily in red and far‐red, that are important in many aspects of plant development. These studies investigated the role of phytochromes in phototropism and gravitropism of seedlings of Arabidopsis thaliana. We used two transgenic lines, one which lacked phytochromes specifically in the roots (M0062/UASBVR) and the other lacked phytochromes in the shoots (CAB3::pBVR). These transgenic plants are deficient in the phytochrome chromophore in specific tissues due the expression of biliverdin IXa reductase (BVR), which binds to precursors of the chromophore. Experiments were performed in both light and dark conditions to determine whether roots directly perceive light signals or if the signal is perceived in the shoot and then transmitted to the root during tropistic curvature. Kinetics of tropisms and growth were assayed by standard methods or with a computer‐based feedback system. We found that the perception of red light occurs directly in the root during phototropism in this organ and that signaling also may occur from root to shoot in gravitropism.
Prophylaxis for ribavirin‐related anemia using eicosapentaenoic acid in chronic hepatitis C patients
Authors: Suzuki Mitsuyoshi , Inage Eisuke , Minowa Kei , Saito Nobutomo , Naritaka Nakayuki , Tsubahara Mayuko , Ohtsuka Yoshikazu , Tokita Akifumi , Shimizu Toshiaki
Published: February 2012

Background:  Ribavirin‐related anemia is a serious side‐effect of the pegylated interferon and ribavirin therapy used for hepatitis C, and may be cause for a reduction in ribavirin dose or even cessation of treatment. The aim of this study was to evaluate the prophylactic effects of oral eicosapentaenoic acid (EPA) supplementation on ribavirin‐induced hemolytic anemia in pediatric and young adult patients.

Methods:  Twelve chronic hepatitis C patients ranging in age from 3 to 21 years (mean, 13.9 ± 5.1 years) who received pegylated interferon α‐2b and ribavirin combination therapy were randomized to either the control group (n= 6) or EPA group (n= 6). Blood samples were collected before, and at 4, 8, and 16 weeks after treatment to measure clinical laboratory parameters.

Results:  The reduction in hemoglobin levels of the EPA group was significantly ameliorated at 8 and 16 weeks when compared to the control group (P < 0.05). There was no significant difference in plasma ribavirin concentrations between the two groups during the treatment. However, one patient in the control group had a reduction in ribavirin dose.

Conclusion:  EPA supplementation prevented ribavirin‐induced hemolytic anemia during combination therapy with pegylated interferon α‐2b and ribavirin in pediatric and young adult patients.
Excitatory effect of propiverine hydrochloride on urethral activity in rats
Authors: Kadekawa Katsumi , Nishijima Saori , Ashitomi Katsuhiro , Yamamoto Hideyuki , Sugaya Kimio
Published: February 2012

Objectives:  To investigate the effects of the antimuscarinic agent, propiverine, on the bladder and urethra in rats.

Methods:  A total of 54 female rats were given propiverine, imidafenacin (an antimuscarinic agent), or distilled water by gavage once or twice daily. After 2 weeks, bladder and urethral activity were recorded under urethane anesthesia. In the propiverine group, the changes of bladder and urethral activity before and after intravenous injection of α1‐adrenergic antagonists (prazosin, silodosin and naftopidil) were also recorded. Furthermore, the leak point pressure after electrical stimulation of abdominal wall muscles was measured in rats with vaginal distension from the control and propiverine groups.

Results:  Intravesical baseline pressure was significantly lower in the propiverine and imidafenacin groups compared with the control group, whereas the urethral baseline pressure was significantly higher in the propiverine group compared with the control or imidafenacin groups. Intravenous injection of prazosin (an α1‐receptor antagonist) significantly decreased the urethral baseline pressure in both of the propiverine and control groups. Intravenous injection of silodosin and naftopidil (α1A‐ and α1D‐receptor antagonists, respectively) significantly decreased the maximum contraction pressure and the urethral baseline pressure in the propiverine group. The leak point pressure of the propiverine group was significantly higher than that of the control group.

Conclusions:  An increase of catecholamines after propiverine administration might activate smooth muscle of the proximal urethra via α1A‐ and α1D‐adrenergic receptors, as well as activating urethral and pelvic floor striated muscle via the spinal motoneurons.
Epigenetics: A way to understand the origin and biology of testicular germ cell tumors
Authors: Okamoto Keisei
Published: February 2012

Testicular germ cell tumors are neoplasms carrying two unique features. First, testicular germ cell tumors have a pluripotential nature and show protean histology ranging from that of germ cells to embryonal and differentiated somatic cells. Therefore, testicular germ cell tumors are interesting resources positioned at a crossroad in developmental and neoplastic processes. The second unique feature of testicular germ cell tumors is their exquisite sensitivity to cisplatin‐based chemotherapy. This review summarizes recent research progress in the epigenetics of testicular germ cell tumors in an attempt to explain the abovementioned biological and clinical characteristics of testicular germ cell tumors.
Current state of medical‐advice‐seeking behaviour for symptoms of colorectal cancer: determinants of failure and delay in medical consultation
Authors: Courtney R. J. , Paul C. L. , Sanson‐Fisher R. W. , Macrae F. , Attia J. , McEvoy M.
Published: March 2012

Aim  There are few data on the factors associated with healthcare‐seeking behaviour for symptoms of colorectal cancer. This study describes the determinants of failure and delay in seeking medical advice for rectal bleeding and change in bowel habit.

Method  In total, 1592 persons (56–88 years) were randomly selected from the Hunter Community Study and mailed a questionnaire.

Results  In all, 18% (60/332) of respondents experiencing rectal bleeding and 20% (39/195) reporting change in bowel habit had never consulted a doctor. The rate of delay (> 1 month) for each symptom was 18% and 37%. The reasons for delay included the assumption that the symptoms were not serious or that they were benign. Triggers for seeking medical advice varied. Healthcare‐seeking behaviour for rectal bleeding had not significantly improved compared with a previous community‐based study.

Conclusion  The seriousness of symptoms, importance of early detection and prompt medical consultation must be articulated in health messages to at‐risk persons.
Openness to Experience as a Predictor of Job Performance Trajectories
Authors: Minbashian Amirali , Earl Joanne , Bright Jim E.H.
Published: February 2012

The present study used a longitudinal design to examine the relationship between openness to experience and 4‐year job performance trajectories for a sample of 129 newly employed professionals. For the typical person, performance increases decelerated over time, plateaued at 2.93 years, and then started to decline thereafter. Openness was not significantly related to initial performance differences or the initial linear rate of growth in performance; however, the performance of individuals high on openness decelerated at a slower rate and started to decline at a later point in time than that of individuals low on openness. We discuss the implications of our findings for theories of job performance and for the use of openness measures in selection contexts.
Immigration and School Choice in Australia
Authors: Mavisakalyan Astghik
Published: March 2012

This article examines the relationship between the share of immigrants in a locality and private versus public school choices of natives and immigrants in Australia. Using the 2001 Australian Census data, it finds that private school attendance among native‐born Australians is higher in localities with a higher share of immigrant populations. Immigrants’ private school attendance is lower where the share of their like‐type immigrants is higher. These effects vary with the presence of a common language and ethnic background between the natives and the immigrants. Overall, the results suggest the possibility of a ‘flight’ from unfamiliar cultures in the Australian school system.
Regulating Synthetic Securitisation Following the Global Financial Crisis
Authors: Podolski Edward J.
Published: March 2012

This article explores whether proposed changes to the regulation of synthetic securitisation in Australia are sufficient in light of the Global Financial Crisis. Synthetic securitisation is specifically chosen as an object of study, given the relative ease with which it can be over‐used. The article examines several theoretical problems with securitisation, which entice corporations into excessively risky behaviour. Contrary to popular belief, it is established that agency issues are not a serious problem with securitisation. Instead, managerial behavioural biases are shown to be most problematic. The article recommends stricter capital adequacy relief requirements, which would provide a disincentive for excessive risk‐taking by potentially over‐confident managers.
For the Student: Matching and Economic Design
Authors: Artemov Georgy , Feldmann Sven , Loertscher Simon
Published: March 2012

This article presents a brief survey of two‐sided matching. We introduce the reader to the problem of two‐sided matching in the context of the college admission model and explain two central requirements for a matching mechanism: stability and non‐manipulability. We show how the frequently used ‘Boston Mechanism’ fails these key requirements and describe how an alternative, the Deferred Acceptance Algorithm, leads to stable matchings but fails to be non‐manipulable in general. A third mechanism, the Top Trading Cycle, is efficient and non‐manipulable when only one side of the match acts strategically. We also discuss some applications of matching theory.
Policy Forum: Designing a Carbon Price Policy: Using Market‐Based Mechanisms for Emission Abatement: Are the Assumptions Plausible?
Authors: Ergas Henry
Published: March 2012

Support for using market‐based mechanisms (carbon taxes or emission‐trading systems) to deal with climate change is based on a number of premises. This article discusses those premises, focusing on the claim that the promise of ever‐rising implied carbon prices under such market‐based mechanisms will support induced innovation in low‐ or no‐carbon technologies. It notes that this claim assumes that promise to be credible and sufficient to induce the innovations required. It argues that the assumed credibility of such very long commitments is questionable, and hence, even in the best of worlds, the implied benefits are unlikely to arise. For a small country like Australia, the problems are then compounded by the absence of a credible, global agreement on emission reduction. Given that, the marginal benefits of investing in carbon abatement are likely to be very low or negative.
Designing a Carbon Price Policy: Introduction
Authors: Lloyd Peter
Published: March 2012

This introduction outlines the main choices that the Australian Government had in designing a carbon price policy. It concludes with an assessment of the findings of the articles in this Policy Forum.
Policy Forum: Designing a Carbon Price Policy: Reducing Greenhouse Gas Emissions at the Lowest Cost
Authors: Freebairn John
Published: March 2012

Arguments for using a tax or an emission‐trading scheme on a comprehensive base of greenhouse gas emissions as a lower‐cost way of reducing pollution than regulations or subsidies are explained. While the Australian Government's ‘Clean Energy Future’ scheme, with its proposal for a price on carbon, moves in the low‐cost direction, the base is less than comprehensive and the scheme persists with, and in important ways increases the roles of, cost‐ineffective regulations and subsidies.
Policy Forum: Designing a Carbon Price Policy: Is the Australian Climate Plan Fair to Australia's Energy‐Intensive, Trade‐Exposed Industries?
Authors: Clarke Harry , Waschik Robert
Published: March 2012

The implications of Australia's unilateral carbon‐pricing plan for its energy‐intensive, trade‐exposed industries are analysed. While a priori arguments for protecting such industries make good theoretical sense, empirically significant levels of support for such protection centre on the non‐ferrous metal industry alone.
Data Survey: Developing the Statistical Longitudinal Census Dataset and Identifying Its Potential Uses
Authors: Zhang Guangyu , Campbell Paul
Published: March 2012

A number of longitudinal surveys have been run in Australia since the 1990s. Recognising the increasing community demand for longitudinal data, the Australian Bureau of Statistics embarked on the creation of a longitudinal dataset, based on the Australian Census of Population and Housing. The key feature of this project is to link a 5 per cent sample of the 2006 Census to subsequent Censuses using a combination of variables available on the Census, thus forming a Statistical Longitudinal Census Dataset (SLCD). This article aims to provide the research community with an overview of the SLCD.