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This article describes the use of cytogenomic and molecular approaches to explore the origin and evolution of Cardamine schulzii, a textbook example of a recent allopolyploid, in its ;110-year history of human-induced hybridization and allopolyploidy in the Swiss Alps. Triploids are typically viewed as bridges between diploids and tetraploids but rarely as parental genomes of high-level hybrids and polyploids. The genome of the triploid semifertile hybrid Cardamine 3 insueta (2n = 24, RRA) was shown to combine the parental genomes of two diploid (2n =2 x = 16) species, Cardamine amara (AA) and Cardamine rivularis (RR). These parental genomes have remained structurally stable within the triploid genome over the >100 years since its origin. Furthermore, we provide compelling evidence that the alleged recent polyploid C. schulzii is not an autohexaploid derivative of C. 3 insueta. Instead, at least two hybridization events involving C. 3 insueta and the hypotetraploid Cardamine pratensis (PPPP, 2n =4 x22 = 30) have resulted in the origin of the trigenomic hypopentaploid (2n =5 x22 = 38, PPRRA) and hypohexaploid (2n =6 x22 = 46, PPPPRA). These data show that the semifertile triploid hybrid can promote a merger of three different genomes and demonstrate how important it is to reexamine the routinely repeated textbook examples using modern techniques.

Ralstonia eutropha is a facultative chemolithoautotrophic bacterium that uses the Calvin-Benson-Bassham (CBB) cycle for CO2 fixation. This study showed that R. eutropha strain H16G incorporated (13)CO2, emitted by the oxidative decarboxylation of [1-(13)C1]-glucose, into key metabolites of the CBB cycle and finally into poly(3-hydroxybutyrate) [P(3HB)] with up to 5.6% (13)C abundance. The carbon yield of P(3HB) produced from glucose by the strain H16G was 1.2 times higher than that by the CBB cycle-inactivated mutants, in agreement with the possible fixation of CO2 estimated from the balance of energy and reducing equivalents through sugar degradation integrated with the CBB cycle. The results proved that the 'gratuitously' functional CBB cycle in R. eutropha under aerobic heterotrophic conditions participated in the reutilization of CO2 emitted during sugar degradation, leading to an advantage expressed as increased carbon yield of the storage compound. This is a new insight into the role of the CBB cycle, and may be applicable for more efficient utilization of biomass resources.

Allopolyploidization combines parental genomes and often confers broader species distribution. However, little is known about parentally transmitted gene expression underlying quantitative traits following allopolyploidization because of the complexity of polyploid genomes. The allopolyploid species Arabidopsis kamchatica is a natural hybrid of the zinc hyperaccumulator Arabidopsis halleri and of the nonaccumulator Arabidopsis lyrata. We found that A. kamchatica retained the ability to hyperaccumulate zinc from A. halleri and grows in soils with both low and high metal content. Hyperaccumulation of zinc by A. kamchatica was reduced to about half of A. halleri, but is 10-fold greater than A. lyrata. Homeologs derived from A. halleri had significantly higher levels of expression of genes such as HEAVY METAL ATPASE4 (HMA4), METAL TRANSPORTER PROTEIN1 and other metal ion transporters than those derived from A. lyrata, which suggests cis-regulatory differences. A. kamchatica has on average about half the expression of these genes compared with A. halleri due to fixed heterozygosity inherent in allopolyploids. Zinc treatment significantly changed the ratios of expression of 1% of homeologous pairs, including genes putatively involved in metal homeostasis. Resequencing data showed a significant reduction in genetic diversity over a large genomic region (290 kb) surrounding the HMA4 locus derived from the A. halleri parent compared with the syntenic A. lyrata-derived region, which suggests different evolutionary histories. We also estimated that three A. halleri-derived HMA4 copies are present in A. kamchatica. Our findings support a transcriptomic model in which environment-related transcriptional patterns of both parents are conserved but attenuated in the allopolyploids., Molecular Biology and Evolution, 33 (11), ISSN:0737-4038, ISSN:1537-1719

We determined the environmental requirements for Lepus brachyurus lyoni on Sado Island, Japan, during the winter when food resources are low. Hare track survey sites were classified by vegetation type. The movement distances of hares, which indicated habitat preference, were evaluated as the relative length of tracks in a 1-ha area. In addition, we examined browse marks on plants and the protein content of plants to determine the preferred plant species. Movement distances of hares decreased significantly with increasing tree stand height, mean tree diameter, basal area of the tree stand, and forest canopy closure, but increased with branch-and-stem density. The percentage of browse marks on the branches of tree/shrub species decreased significantly with increasing branch-and-stem diameter. The rate of feeding increased significantly with increased protein content in the branches. These findings suggest that hares prefer shrub stands with high branch-and-stem density to mature forests, which hav...

Polyploidization, or genome duplication, has played a critical role in the diversification of animals, fungi and plants. Little is known about the population structure and multiple origins of polyploid species because of the difficulty in identifying multiple homeologous nuclear genes. The allotetraploid species Arabidopsis kamchatica is closely related to the model species Arabidopsis thaliana and is distributed in a broader climatic niche than its parental species. Here, we performed direct sequencing of homeologous pairs of the low-copy nuclear genes WER and CHS by designing homeolog-specific primers, and obtained also chloroplast and ribosomal internal transcribed spacer sequences. Phylogenetic analysis showed that 50 individuals covering the distribution range including North America are allopolyploids derived from Arabidopsis lyrata and Arabidopsis halleri. Three major clusters within A. kamchatica were detected using Bayesian clustering. One cluster has widespread distribution. The other two are restricted to the southern part of the distribution range including Japan, where the parent A. lyrata is not currently distributed. This suggests that the mountains in Central Honshu and surrounding areas in Japan served as refugia during glacial-interglacial cycles and retained this diversity. We also found that multiple haplotypes of nuclear and chloroplast sequences of A. kamchatica are identical to those of their parental species. This indicates that multiple diploid individuals contributed to the origin of A. kamchatica. The haplotypes of low-copy nuclear genes in Japan suggest independent polyploidization events rather than introgression. Our findings suggest that self-compatibility and gene silencing occurred independently in different origins.

We investigated the substrate specificity of farnesyl diphosphate (FPP) synthase derived from Bacillus stearothermophilus and porcine liver by examining the reactivities of two cyclic substrate homologs, cyclohexylideneethyl diphosphate and cyclohexenylethyl diphosphate. Reaction of geranyl diphosphate with 2-cyclohexenylethyl diphosphate using bacterial or porcine liver FPP synthase produced (S)-geranylcyclohexylideneethyl diphosphate, with relative yields of 13.6% for the bacterial enzyme and 42.2% for the porcine liver enzyme. Reaction of cyclohexylideneethyl diphosphate with isopentenyl diphosphate produced 10-cyclohexyliden-3,7-dimethyldeca-2,6-dien-1-ol as a double condensation product, with relative yields of 23.1% (bacterial enzyme) and 3.0% (porcine liver enzyme). Reaction of cyclohexylideneethyl diphosphate with 2-cyclohexenylethyl diphosphate using bacterial enzyme produced (cyclohexylideneethyl)-cyclohexylideneethyl diphosphate (0.8% yield).

We present the technique of instrumental delay calibration for the dual-beam system of VLBI Exploration of Radio Astrometry (VERA), namely, the horn-on-dish method, in which artificial noise sources are mounted on the antenna feedome base and a wide-band radio noise is injected into the dual-beam receivers after reflection by a subreflector. We introduce the basic concept of calibration with the horn-on-dish method, and also present results of the experiments to evaluate its calibration accuracy. Detailed comparisons between model path calculations and measured paths from the noise sources show that the horn-on-dish method can calibrate the dual-beam delay difference in the antenna structure and receiver within an � 0.1 mm level. We estimated that the systematic error in

We observed the SiO (v = 1 and v = 2, J = 1–0) maser emissions toward the Mira variable IK Tauri (IK Tau, NML Tau, IRC +10050) over nine epochs from 2003 November to 2005 April using the VLBI Exploration of Radio Astrometry (VERA) telescope array. We found that the SiO maser distributions around IK Tau are highly variable, depending on the stellar pulsation phase. The velocity structures were complex and also time-variable, and are inconsistent with a simply rotating shell that was suggested by previous observations. Based on fittings of the SiO maser distributions to elliptical ring models, we found that the ring size seems to vary in correlation with the pulsation phase, as previously found for TX Cam. Comparisons of the v = 1 and v = 2 maser distributions reveal that 42–50% of the maser pairs have a positional offset less than 0.5 mas, suggesting that the maser pumping in these spots is likely to be dominated by line overlapping or collisional pumping, rather than pure radiative pumping. In order to model the velocity structure of the spoke-like features observed in IK Tau, we propose a ballistic-orbit model, in which a gas clump ejected from the stellar surface moves radially outward with a gravitational deceleration, and argue that the stellar mass can be deduced from that model.

We report on results of five-epoch VLBI observations of H2O maser emission in the M-type star IRC � 10414, carried out with the VLBI Exploration of Radio Astrometry (VERA). The maser distribution extends over an area of 70 mas � 260 mas and exhibits a bipolar structure. The relative proper motions of 17 maser features were measured during the monitoring observations spanning nine months. The distance to IRC � 10414 was re-estimated on the basis of the statistical treatment of parallax and the model-fitting method, yielding D = 3.1 ˙ 0.4 kpc and D = 2.0 ˙ 0.2 kpc, respectively. The estimated distance, D = 2–3 kpc, is much larger than that previously adopted. The stellar luminosity of IRC � 10414 is also re-estimated to be L� � 9 � 10 4 (D=2 kpc) 2 Lˇ, much brighter by a factor of 10–20 than previously adopted (L� � 10000 Lˇ). The maser motions exhibit not only a spherically expanding flow with a velocity of � 10 (D=2 kpc) km s � 1 , but also a faster bipolar outflow with a major axis in the north–south direction and at a small inclination angle with respect to the celestial sphere. These characteristics of the star and the

The evolution from outcrossing based on self-incompatibility (SI) to a selfing system is one of the most prevalent transitions in flowering plants. It has been suggested that the loss of SI in Arabidopsis thaliana is associated with pseudogene formation at the SCR male component of the S locus. Recent work, however, suggests that alternative alleles with large deletions at the S locus are also present and may be responsible for the evolution of self-compatibility in this species. We demonstrate that most of these deletion alleles are evolutionarily derived from an S haplotype (haplogroups A) that already possessed the SCR pseudogene. This haplotype and its deletion variants are nearly fixed in Europe. Together with previous transgenic data, these results suggest that the pseudogenization of PsiSCR1 gene changed the SI phenotype in the majority of A. thaliana accessions, and was a critical step in the evolution of selfing in this species. Two other haplogroups (B and C) were also identified, the former of which contains a novel and possibly functional SCR allele. In contrast to haplogroups A, these two haplogroups are found primarily in Africa and Asia. These results suggest that self-compatibility, which appears to be fixed in this species, arose multiple times with different genetic bases, and indicates that a species-specific trait is associated with parallel evolution at the molecular level.

We report on results of multi-epoch VLBI observations of H2O masers associated with a low-mass young stellar object, IRAS 16293 2422 in Oph East, and a fringe-phase and position reference source, ICRF J162546.8 252738, using the VLBI Exploration of Radio Astrometry (VERA) for high-precision astrometry. We obtained an annual parallax of a maser feature to be = 5.6 0:5 mas, corresponding to a distance of D= 178 +18 37 pc. We also found 10 relative proper motions of maser features with respect to the maser feature mentioned above. The motion of the accompanying young stellar object (YSO) has already been found in thermal continuum emission previously observed with the Very Large Array. The intrinsic motions of masers have been estimated from the relative proper motions after the YSO’s motion is subtracted from, and a systemic secular motion of the position reference feature is added to the proper motions originally measured. The intrinsic maser kinematical structure may trace a bipolar outflow.

53歳，男性。初診の約3週間前より両手指から手背にかけて，疼痛・しびれを伴う浮腫が出現し，左第1指から第3指にかけては紫紅色調の紅斑も伴っていた。これらの症状は消炎鎮痛薬内服，ステロイド外用では改善しなかった。当科初診時，末梢血好酸球増多(1748/μl)があり，皮膚所見と合わせ，episodic angioedema with eosinophiliaを疑った。ところが加療中も，足背浮腫や，右示指に冷感を伴ったチアノーゼ，網状皮斑が出現し，さらには血痰も伴うようになった。再検したところ，好酸球増多は進行し(7951/μl)，血管内播種性凝固症候群(DIC)を伴っていることが判明した。好酸球増多について骨髄検査を含めて精査を行ったが明らかな異常はなく，最終的にhypereosinophilic syndrome(HES)と診断した。治療はHESに対してpredonisolone 60mg，DICに対してgabexate mesilateで治療を開始し，軽快した。初診時でのHES の診断は困難であるが，本症例のように非典型的な手の浮腫を認めた場合にはHESも含めた鑑別を挙げる必要があると考えられた。

Genomewide markers enable us to study genetic differentiation within a species and the factors underlying it at a much higher resolution than before, which advances our understanding of adaptation in organisms. We investigated genomic divergence in Metrosideros polymorpha, a woody species that occupies a wide range of ecological habitats across the Hawaiian Islands and shows remarkable phenotypic variation. Using 1659 single nucleotide polymorphism (SNP) markers annotated with the genome assembly, we examined the population genetic structure and demographic history of nine populations across five elevations and two ages of substrates on Mauna Loa, the island of Hawaii. The nine populations were differentiated into two genetic clusters distributed on the lower and higher elevations and were largely admixed on the middle elevation. Demographic modelling revealed that the two genetic clusters have been maintained in the face of gene flow, and the effective population size of the high-altitude cluster was much smaller. A FST -based outlier search among the 1659 SNPs revealed that 34 SNPs (2.05%) were likely to be under divergent selection and the allele frequencies of 21 of them were associated with environmental changes along elevations, such as temperature and precipitation. This study shows a genomic mosaic of M. polymorpha, in which contrasting divergence patterns were found. While most genomic polymorphisms were shared among populations, a small fraction of the genome was significantly differentiated between populations in diverse environments and could be responsible for the dramatic adaptation to a wide range of environments.

Ralstonia eutropha is a facultative chemolithoautotrophic bacterium that uses the Calvin–Benson–Bassham (CBB) cycle for CO2 fixation. This study showed that R. eutropha strain H16G incorporated 13CO2, emitted by the oxidative decarboxylation of [1-13C1]-glucose, into key metabolites of the CBB cycle and finally into poly(3-hydroxybutyrate) [P(3HB)] with up to 5.6% 13C abundance. The carbon yield of P(3HB) produced from glucose by the strain H16G was 1.2 times higher than that by the CBB cycle-inactivated mutants, in agreement with the possible fixation of CO2 estimated from the balance of energy and reducing equivalents through sugar degradation integrated with the CBB cycle. The results proved that the ‘gratuitously’ functional CBB cycle in R. eutropha under aerobic heterotrophic conditions participated in the reutilization of CO2 emitted during sugar degradation, leading to an advantage expressed as increased carbon yield of the storage compound. This is a new insight into the role of the CBB cycle and may be applicable for more efficient utilization of biomass resources.

Self-incompatibility (SI) systems in flowering plants distinguish self- and non-self pollen to prevent inbreeding. While other SI systems rely on the self-recognition between specific male- and female-determinants, the Solanaceae family has a non-self recognition system resulting in the detoxification of female-determinants of S-ribonucleases (S-RNases), expressed in pistils, by multiple male-determinants of S-locus F-box proteins (SLFs), expressed in pollen. It is not known how many SLF components of this non-self recognition system there are in Solanaceae species, or how they evolved. We identified 16?20 SLFs in each S-haplotype in SI Petunia, from a total of 168 SLF sequences using large-scale next-generation sequencing and genomic polymerase chain reaction (PCR) techniques. We predicted the target S-RNases of SLFs by assuming that a particular S-allele must not have a conserved SLF that recognizes its own S-RNase, and validated these predictions by transformation experiments. A simple mathematical model confirmed that 16?20 SLF sequences would be adequate to recognize the vast majority of target S-RNases. We found evidence of gene conversion events, which we suggest are essential to the constitution of a non-self recognition system and also contribute to self-compatible mutations., [プレスリリース]植物が自分以外の花粉を選ぶための遺伝子セットを特定！ ～生物の非自己認識システムの進化の謎解明へ～, [Author's version title]Gene duplication and genetic exchange drive the evolution of S-RNase based self-incompatibility

To evaluate the effect of low-molecular-weight glutenin subunit (LMW-GS) genes on dough strength, locus-specific primers of LMW-GS genes and gliadin bands tightly linked to LMW-GS genes were analyzed in common wheat. Segregation analysis of the F2 progeny from a cross between ‘Haruhikari’, a good bread-making quality cultivar, and ‘Asakaze-komugi’, a poor bread-making quality cultivar, showed that dough strength significantly correlated with one amplified LMW-GS gene located at the Glu-B3 locus from ‘Haruhikari’. There was no specific reference to the gliadin bands identified as promising markers in the cross under study. The LMW-GS gene of ‘Haruhikari’ had a seven amino-acid deletion in the repetitive domain relative to ‘Asakaze-komugi’, as well as six amino-acid substitutions, three of which would be expected to cause changes in hydrophilicity. The presence of the LMW-GS gene and other LMW-GS genes tightly linked to it may affect the dough strength of wheat.

In magnesia cement, phase 3, a broad and strong infrared band was observed with the maximum at ∼1300 and 1050 cm −1 in the H and D systems, respectively. To clarify the origin of the 1300 cm −1 band the temperature dependency of the infrared spectra of the H system was observed and the spectra analyzed on the basis of a strong vibrational coupling of the OH stretching with lattice modes. The fitting was quite well, giving rise to the origin of the 1300 cm −1 band of the OH stretching.

The theoretical study on the mechanism of butane oxidation using model complexes of vanadyl pyrophosphate has been investigated using density functional theory (DFT) method. The monomeric complex VO(OH) 2 (OH 2 ) 2 was selected as a fundamental structure. The complexes bearing one phosphoric residue were selected for clarifying the effect of pyrophosphoric moieties on the catalyst. The complexes having two vanadium units were selected as two-layer models of the catalyst for clarifying the influence of the presence or absence of lattice oxygen and the effect of the oxidation states of the inner vanadium atom. The introduction of a phosphoric moiety on one of the hydroxy groups strongly stabilizes the lower oxidation states of the complexes. This result suggests that the surface vanadium species having the higher 5+ oxidation state should possess stronger oxidation ability. The presence of the vanadium (4+) atom at the lower layer relatively destabilizes the V 3+ state of the upper vanadium complexes, and stabilizes the peroxo-vanadium (4+) complexes, which suggests that the lattice oxo-oxygen in vanadyl pyrophosphate may play an important role in the activation of molecular oxygen.

Introduction of fluorine atom(s) at the γ- and δ-positions of alkyl iodides increased the selectivities toward palladium-catalyzed cross-coupling reaction with organostannanes. A similar effect of fluorine substituents on the selectivities was also observed in the palladium-catalyzed carbonylative coupling reaction of alkyl iodides with phenyltributyltin under CO pressure.

Branchio-oto (BO) syndrome is complicated with congenital preauricular fistulae, branchial fistulae (cysts), and hearing loss (sensorineural, conductive or mixed). As well as branchio-oto-renal (BOR) syndrome, it is known to be an autosomal dominant hereditary disorder. Since mutations in the EYA1 gene have been identified in both BO and BOR syndromes, mutation screening of this gene has been drawing attention as a genetic test to diagnose BOR/BO syndromes. In this study, we genetically investigated the presence of EYA1 mutations in a BO syndrome family in which we observed congenital preauricular fistulae, branchial fistulae (cysts) and hearing loss in four generations. Whereas there was a variety of phenotype expressions in this family, all subjects tested had a nonsense mutation (R264X) in exon 8 of the EYA1 gene. The present report adds further examples to support the usefulness of molecular genetic testing for the diagnosis of patients with BO syndrome.

β-Perfluoroalkyl-substituted alkyl halides reacted with organostamnanes such as allylphenylethynyl-, β-phenylethenyl-, and phenyl-tributyltin in the presence of palladium-phosphine complexes to give the corresponding cross-coupling products in good yields. When the reaction was carried out under CO pressure, carbonylative coupling of the halides took place affording the corresponding fluorine-contaming ketones in good yields.

Coupling reaction of β-perfluoroalkyl-substituted alkyl halides with Grignard reagents such as phenyl-, vinyl-, allyl-, benzyl-, and alkyl-magnesium halides was catalyzed by copper salts or complexes to give the corresponding cross-coupling products in good yields. α,ω-Diiodoalkane bearing a polyfluoroalkylene moiety also reacted with 2 equiv. of Grignard reagent in the presence of copper catalyst to give α,ω-bi-functionalized product.

Finding causal relationships between genotypic and phenotypic variation is a key focus of evolutionary biology, human genetics and plant breeding. To identify genome-wide patterns underlying trait diversity, we assembled a high-quality reference genome of Cardamine hirsuta, a close relative of the model plant Arabidopsis thaliana. We combined comparative genome and transcriptome analyses with the experimental tools available in C. hirsuta to investigate gene function and phenotypic diversification. Our findings highlight the prevalent role of transcription factors and tandem gene duplications in morphological evolution. We identified a specific role for the transcriptional regulators PLETHORA5/7 in shaping leaf diversity and link tandem gene duplication with differential gene expression in the explosive seed pod of C. hirsuta. Our work highlights the value of comparative approaches in genetically tractable species to understand the genetic basis for evolutionary change.

The genus Nepenthes, a carnivorous plant, has a pitcher to trap insects and digest them in the contained fluid to gain nutrient. A distinctive character of the pitcher fluid is the digestive enzyme activity that may be derived from plants and dwelling microbes. However, little is known about in situ digestive enzymes in the fluid. Here we examined the pitcher fluid from four species of Nepenthes. High bacterial density was observed within the fluids, ranging from 7×10(6) to 2.2×10(8) cells ml(-1). We measured the activity of three common enzymes in the fluid: acid phosphatases, β-D-glucosidases, and β-D-glucosaminidases. All the tested enzymes detected in the liquid of all the pitcher species showed activity that considerably exceeded that observed in aquatic environments such as freshwater, seawater, and sediment. Our results indicate that high enzyme activity within a pitcher could assist in the rapid decomposition of prey to maximize efficient nutrient use. In addition, we filtered the fluid to distinguish between dissolved enzyme activity and particle-bound activity. As a result, filtration treatment significantly decreased the activity in all enzymes, while pH value and Nepenthes species did not affect the enzyme activity. It suggested that enzymes bound to bacteria and other organic particles also would significantly contribute to the total enzyme activity of the fluid. Since organic particles are themselves usually colonized by attached and highly active bacteria, it is possible that microbe-derived enzymes also play an important role in nutrient recycling within the fluid and affect the metabolism of the Nepenthes pitcher plant.

Coupling reaction of β-perfluoroalkyl-substituted alkyl halides with Grignard reagents such as phenyl-, vinyl-, allyl-, benzyl-, and alkyl-magnesium halides was catalyzed by copper salts or complexes to give the corresponding cross-coupling products in good yields. α,ω-Diiodoalkane bearing a polyfluoroalkylene moiety also reacted with 2 equiv. of Grignard reagent in the presence of copper catalyst to give α,ω-bi-functionalized product.

β-Perfluoroalkyl-substituted alkyl halides reacted with organostamnanes such as allylphenylethynyl-, β-phenylethenyl-, and phenyl-tributyltin in the presence of palladium-phosphine complexes to give the corresponding cross-coupling products in good yields. When the reaction was carried out under CO pressure, carbonylative coupling of the halides took place affording the corresponding fluorine-contaming ketones in good yields.

Dehydrogenative silylation of terminal alkynes with hydrosilanes proceeds in the presence of iridium catalyst to afford the corresponding silylacetylenes. When phenylacetylene and triethylsilane were heated in dry DME in the presence of Ir4(CO)12–PPh3, (2-phenylethynyl)triethylsilane was obtained in 96% yield with little of hydrosilylated products. The present method is applicable for a variety of terminal alkynes and hydrosilanes to give the corresponding silylacetylenes in good yields with high selectivities.

Introduction of fluorine atom(s) at the γ- and δ-positions of alkyl iodides increased the selectivities toward palladium-catalyzed cross-coupling reaction with organostannanes. A similar effect of fluorine substituents on the selectivities was also observed in the palladium-catalyzed carbonylative coupling reaction of alkyl iodides with phenyltributyltin under CO pressure.

Ever since Darwin's pioneering research, the evolution of self-fertilisation (selfing) has been regarded as one of the most prevalent evolutionary transitions in flowering plants. A major mechanism to prevent selfing is the self-incompatibility (SI) recognition system, which consists of male and female specificity genes at the S-locus and SI modifier genes. Under conditions that favour selfing, mutations disabling the male recognition component are predicted to enjoy a relative advantage over those disabling the female component, because male mutations would increase through both pollen and seeds whereas female mutations would increase only through seeds. Despite many studies on the genetic basis of loss of SI in the predominantly selfing plant Arabidopsis thaliana, it remains unknown whether selfing arose through mutations in the female specificity gene (S-receptor kinase, SRK), male specificity gene (S-locus cysteine-rich protein, SCR; also known as S-locus protein 11, SP11) or modifier genes, and whether any of them rose to high frequency across large geographic regions. Here we report that a disruptive 213-base-pair (bp) inversion in the SCR gene (or its derivative haplotypes with deletions encompassing the entire SCR-A and a large portion of SRK-A) is found in 95% of European accessions, which contrasts with the genome-wide pattern of polymorphism in European A. thaliana. Importantly, interspecific crossings using Arabidopsis halleri as a pollen donor reveal that some A. thaliana accessions, including Wei-1, retain the female SI reaction, suggesting that all female components including SRK are still functional. Moreover, when the 213-bp inversion in SCR was inverted and expressed in transgenic Wei-1 plants, the functional SCR restored the SI reaction. The inversion within SCR is the first mutation disrupting SI shown to be nearly fixed in geographically wide samples, and its prevalence is consistent with theoretical predictions regarding the evolutionary advantage of mutations in male components.

The evolution from outcrossing based on self-incompatibility (SI) to a selfing system is one of the most prevalent transitions in flowering plants. It has been suggested that the loss of SI in Arabidopsis thaliana is associated with pseudogene formation at the SCR male component of the S locus. Recent work, however, suggests that alternative alleles with large deletions at the S locus are also present and may be responsible for the evolution of self-compatibility in this species. We demonstrate that most of these deletion alleles are evolutionarily derived from an S haplotype (haplogroups A) that already possessed the SCR pseudogene. This haplotype and its deletion variants are nearly fixed in Europe. Together with previous transgenic data, these results suggest that the pseudogenization of PsiSCR1 gene changed the SI phenotype in the majority of A. thaliana accessions, and was a critical step in the evolution of selfing in this species. Two other haplogroups (B and C) were also identified, the former of which contains a novel and possibly functional SCR allele. In contrast to haplogroups A, these two haplogroups are found primarily in Africa and Asia. These results suggest that self-compatibility, which appears to be fixed in this species, arose multiple times with different genetic bases, and indicates that a species-specific trait is associated with parallel evolution at the molecular level.

L'oxydation des derives du tosylamide en presence d'ions halogenures est etudiee dans des solutions de methanol et de methanolate de sodium

In magnesia cement, phase 3, a broad and strong infrared band was observed with the maximum at approximately 1300 and 1050 cm(-1) in the H and D systems, respectively. To clarify the origin of the 1300 cm(-1) band the temperature dependency of the infrared spectra of the H system was observed and the spectra analyzed on the basis of a strong vibrational coupling of the OH stretching with lattice modes. The fitting was quite well, giving rise to the origin of the 1300 cm(-1) band of the OH stretching.

In this paper, we propose FD-MC/CDMA system in which one information symbol is transmitted using minimum K frequency carriers to obtain the full diversity effect where K can be less than the full signal space dimension N. Moreover, we demonstrate the proposed cancellation scheme based on MMSE algorithm in FD-MC/CDMA system with low computational complexity achieves performances very close to that of the optimum ML detector.

Genome duplication with hybridization, or allopolyploidization, occurs commonly in plants, and is considered to be a strong force for generating new species. However, genome-wide quantification of homeolog expression ratios was technically hindered because of the high homology between homeologous gene pairs. To quantify the homeolog expression ratio using RNA-seq obtained from polyploids, a new method named HomeoRoq was developed, in which the genomic origin of sequencing reads was estimated using mismatches between the read and each parental genome. To verify this method, we first assembled the two diploid parental genomes of Arabidopsis halleri subsp. gemmifera and Arabidopsis lyrata subsp. petraea (Arabidopsis petraea subsp. umbrosa), then generated a synthetic allotetraploid, mimicking the natural allopolyploid Arabidopsis kamchatica. The quantified ratios corresponded well to those obtained by Pyrosequencing. We found that the ratios of homeologs before and after cold stress treatment were highly correlated (r = 0.870). This highlights the presence of nonstochastic polyploid gene regulation despite previous research identifying stochastic variation in expression. Moreover, our new statistical test incorporating overdispersion identified 226 homeologs (1.11% of 20 369 expressed homeologs) with significant ratio changes, many of which were related to stress responses. HomeoRoq would contribute to the study of the genes responsible for polyploid-specific environmental responses.

In order to search for new VLBI sources in the Galactic plane that can be used as phase reference sources in differential VLBI, we have conducted 22 GHz observations of radio sources in the Galactic plane using the Japanese VLBI Network (J-Net). We have observed 267 VLBI source candidates selected from existing radio surveys and have detected 93 sources at the signal-to-noise ratio larger than 5. While 42 of the 93 detected sources had already been detected with VLBI at relatively lower frequency (typically 2 to 8 GHz), the remaining 51 are found to be new VLBI sources detected for the first time. These VLBI sources are located within $|b|\le 5^\circ$, and have a large number of Galactic maser sources around them. Thus, they are potential candidates for phase reference sources for VLBI Exploration of Radio Astrometry (VERA), which is the first VLBI array dedicated to the phase referencing VLBI astrometry aiming at measuring the parallax and proper motion of maser sources in the whole Galaxy., Comment: to be published in PASJ (2000, Vol.52, No.5), 13 pages and 2 figures

Background Ralstonia eutropha H16 is well known to produce polyhydroxyalkanoates (PHAs), which are potential bio-based biodegradable plastics, in an efficient manner as an energy storage material under unbalanced growth conditions. To obtain further knowledge of PHA biosynthesis, this study performed a quantitative transcriptome analysis based on deep sequencing of the complementary DNA generated from the RNA (RNA-seq) of R. eutropha H16. Results Total RNAs were extracted from R. eutropha cells in growth, PHA production, and stationary phases on fructose. rRNAs in the preparation were removed by repeated treatments with magnetic beads specific to bacterial rRNAs, and then the 36 bp sequences were determined using an Illumina high-throughput sequencer. The RNA-seq results indicated the induction of gene expression for transcription, translation, cell division, peptidoglycan biosynthesis, pilus and flagella assembly, energy conservation, and fatty acid biosynthesis in the growth phase; and the repression trends of genes involved in central metabolisms in the PHA production phase. Interestingly, the transcription of genes for Calvin-Benson-Bassham (CBB) cycle and several genes for β-oxidation were significantly induced in the PHA production phase even when the cells were grown on fructose. Moreover, incorporation of 13C was observed in poly(3-hydroxybutyrate) synthesized by R. eutropha H16 from fructose in the presence of NaH13CO3, and further gene deletion analyses revealed that both of the two ribulose 1,5-bisphosphate carboxylase (Rubiscos) in CBB cycle were actually functional in CO2 fixation under the heterotrophic condition. Conclusions The results revealed the phase-dependent transcriptomic changes and a CO2 fixation capability under heterotrophic conditions by PHA-producing R. eutropha.

In this paper we discuss the potential use of VERA (VLBI exploration of radio astrometry) to study black holes based on phase-referencing VLBI astrometry. First we present a brief overview of the project, from system design to scientific targets, and then we discuss the possibilities to investigate black holes and other high energy phenomena that are possibly linked to black holes.

1,2,3,4-Tetra-t-butylnaphthalene (2), a highly crowded naphthalene derivative, has been synthesized. Upon irradiation, 2 underwent photovalence isomerization to afford 1,2,5,6-tetra-t-butyl-3,4-benzo-3-tricyclo[3.1.0.02,6]-hexene (3). The synthesis of 1,4,5,6-tetra-t-butyl-2,3-benzo-2,5-bicyclo[2.2.0]hexadiene (1), which was used for the synthesis of 2, is also described.

Two forms of erythropoietin, EPO-bi and EPO-tetra, with different biological activities were isolated from the culture medium of a recombinant Chinese hamster ovary cell line, B8-300, into which the human erythropoietin gene had been introduced. EPO-bi, an unusual form, showed only one-seventh the in vivo activity and 3 times higher in vitro activity of the previously described recombinant human EPO (standard EPO). In contrast, EPO-tetra showed both in vivo and in vitro activities comparable to those of the standard EPO. EPO-bi, EPO-tetra, and the standard EPO had the same amino acid composition and immunoreactivity. However, structural analyses of their N-linked sugar chains revealed that EPO-bi contains the biantennary complex type as the major sugar chain, while EPO-tetra and the standard EPO contain the tetraantennary complex type as the major sugar chain. From examination of various preparations of recombinant human EPO, we found a positive correlation between the in vivo activity of EPO and the ratio of tetraantennary to biantennary oligosaccharides. These results suggest that higher branching of the N-linked sugar chains is essential for effective expression of in vivo biological activity of EPO.