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• Compatibility and adsorption of IL/IRMOF-1 was predicted using simulation. • IL/IRMOF-1 shows an improved resistance to water compared to pristine IRMOF-1. • Adsorption of H 2 S and CO 2 was highly dependent on the IL loadings. • The hybrid composite was more selective in capturing H 2 S than CO 2. The compatibility and performance of an Isoreticular Metal-Organic Frameworks (IRMOF-1) impregnated with choline-based ionic liquids (ILs) for selective adsorption of H 2 S/CO 2 , were studied by molecular dynamics (MD) simulation. Cholinium alanate ([Chl][Ala]) was nominated as the suitable IL for impregnation into IRMOF-1, consistent with the low RMSD values (0.546 nm, 0.670 nm, 0.776 nm) at three IL/IRMOF-1 w/w ratios (W IL/IRMOF-1 = 0.4, 0.8, and 1.2). The [Chl]+ and [Ala]− ion pair was located preferentially around the carboxylate group within the IRMOF-1 framework, with the latter interacting strongly with the host than the [Chl]+. Results of radius of gyration (Rg) and root mean square displacement (RMSD) revealed that a ratio of 0.4 w/w of IL/IRMOF-1 (Rg = 1.405 nm; RMSD = 0.546 nm) gave the best conformation to afford an exceptionally stable IL/IRMOF-1 composite. It was discovered that the IL/IRMOF-1 composite was more effective in capturing H 2 S and CO 2 compared to pristine IRMOF-1. The gases adsorbed in higher quantities in the IL/IRMOF-1 composite phase compared to the bulk phase, with a preferential adsorption for H 2 S, as shown by the uppermost values of adsorption (A H 2 S = 17.954 mol L−1 bar-1) and an adsorption selectivity (A S H 2 S / C O 2 = 43.159) at 35 IL loading. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about a modified prefilled syringe to prevent plunger/piston misassembly.

Flexibility has been pursued enthusiastically in the field of porous crystals for enhancing their adsorption and separation performances. However, flexibility has never been observed among porous crystals sustained thoroughly by van der Waals interactions since flexible motions readily lead to the collapse of the porous architecture. Here we report a van der Waals crystal featuring conformational flexibility as well as permanent microporosity. The single-crystal structure and its structural transition in response to the adsorption of water molecules were unambiguously disclosed by means of electron and X-ray crystal structure analyses. The peripheral aromatic rings of the constituent molecule rotated as increasing the ambient humidity, while the connectivity of the pores was maintained throughout the structural transition. The transformative pores allowed the guest water molecules to move exceedingly quickly through the pores with a time constant of 490 μs. We demonstrated that the quick release of water induced by photothermal heating induced a significant upward bending of a film set above the crystalline powder compared to conventional porous materials. This finding contributes to the future crystal engineering based on van der Waals interactions rather than cohesive bonds., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Coacervation, the phase separation of liquid induced by polymeric solutes, sometimes results in the formation of oligomeric clusters of droplets. The morphology of the clusters is non-uniform because the clustering is a consequence of the random collisions of the drifting droplets. Here we report distinctively organized coacervation, yielding colloidal molecules with monodisperse size, morphological symmetry, and compositional heterogeneity. We investigate the coacervation of a mixture of two types of synthetic polymers and find that one of the polymers coacervates first and serves as a core droplet, on which the other polymer coacervates subsequently to form satellite droplets. The satellite droplets arrange themselves symmetrically around the core and solidify without losing the morphology. The number of satellites and their symmetry are modulable depending on the chemical affinity and the diameter of the droplets. This finding highlights the capability of coacervation as a non-templated and non-covalent pathway to form aspherical colloidal materials with structural and functional complexity., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

Key Message: A new restorer of fertility gene, Rfs, of Ogura cytoplasmic male sterility (CMS) in radish encodes a pentatricopeptide repeat protein that binds to 15 nucleotides in mRNA of the CMS gene, orf138. Nucleotide substitutions in both Rfs and orf138 determine effectiveness and specificity of restoration. Cytoplasmic male sterility (CMS) in plants caused by the expression of abnormal mitochondrial genes results from impaired pollen production. The manifestation of CMS is suppressed by the restorer of fertility (Rf) genes in the nuclear genome. Thus, the CMS-Rf system is a suitable model for studying the direct interactions of mitochondrial and nuclear genes. At least nine haplotypes, of which Type B is ancestry, have been reported for the Ogura CMS gene, orf138, in radish (Raphanus sativus). We previously observed that Rfo encoding a pentatricopeptide repeat (PPR) protein, ORF687, which inhibits the translation of orf138 is ineffective in one haplotype (i.e., Type H). Here, we carried out map-based cloning of another Rf gene (Rfs) that cleaves the orf138 mRNA of Type H. Rfs produces a PPR protein consisting of 15 PPR motifs that binds to the mRNA, cleaving the mRNA at about 50nt downstream of the binding site. However, Rfs was ineffective for Type A because of a single nucleotide substitution in the binding site. Both Rfo and Rfs suppress orf138 expression in ancestral Type B, but they are rendered ineffective in Type H and Type A, respectively, by a single nucleotide substitution in orf138., (© 2024. The Author(s).)

A microsphere, assembled from a chiral π-conjugated polymer with narrow polydispersity, features a well-organized twisted-bipolar structure and exhibits highly biased circularly polarized luminescence (CPL). The CPL emitted toward the equatorial direction is 61-fold greater than that emitted along the zenith direction, which is the highest anisotropy among existing microscopic CPL emitters.

Skin is the body barrier that constrains the infiltration of particles and exogenous aggression, in which the hair follicle plays an important role. Recent studies have shown that small particles can penetrate the skin barrier and reach the hair follicle, making them a potential avenue for delivering hair growth-related substances. Interestingly, keratin-based microspheres are widely used as drug delivery carriers in various fields. In this current study, we pursue the effect of newly synthesized 3D spherical keratin particles on inducing hair growth in C57BL/6 male mice and in human hair follicle dermal papilla cells. The microspheres were created from partially sulfonated, water-soluble keratin. The keratin microspheres swelled in water to form spherical gels, which were used for further experiments. Following topical application for a period of 20 days, we observed a regrowth of hair in the previously depleted area on the dorsal part of the mice in the keratin microsphere group. This observation was accompanied by the regulation of hair-growth-related pathways as well as changes in markers associated with epidermal cells, keratin, and collagen. Interestingly, microsphere keratin treatment enhanced the cell proliferation and the expression of hair growth markers in dermal papilla cells. Based on our data, we propose that 3D spherical keratin has the potential to specifically target hair follicle growth and can be employed as a carrier for promoting hair growth-related agents.

Thermally tolerant polymer optical resonators are fabricated from a stereocomplex of poly(L-lactic acid) and poly(D-lactic acid) through the oil-in-water miniemulsion method. The thermal stability of the microspheres of the stereocomplex poly(lactic acid) (SC-PLA) is superior to that of the homochiral poly(lactic acid) (HC-PLA). As a result of the high thermal stability, the optical resonator properties of the SC-PLA microspheres are preserved at an elevated temperature of up to 230 °C, which is 70 °C higher than that of microspheres formed from HC-PLA.

Here, we report an anomalous pathway complexity in the supramolecular polymerization of a chiral monomer, which displays an unusual chiroptical feature that does not follow any of the known stereochemical rules such as "chiral self-sorting" and "majority rule". We newly developed a planar-chiral ferrocene-cored tetratopic pyridyl monomer FcL , which underwent AgBF 4 -mediated supramolecular polymerization to give nanotubes FcNT s composed of metal-organic nanorings FcNR s. Although FcNR s must be homochiral because of a strong geometrical constraint, FcNR s were formed even efficiently from racemic FcL and AgBF 4 . Detailed studies revealed the presence of two competing pathways for producing homochiral FcNR s as the constituents of FcNT s: (i) spontaneous cyclization of initially formed acyclic polymers -[ FcL -Ag + ] n - and (ii) template ( FcNR )-assisted cyclization via a Ag + ···Ag + metallophilic interaction. The dominance of the two pathways changes depending on the % ee of chiral FcL . Namely, when the % ee of FcL is high, -[ FcL -Ag + ] n - must contain sufficiently long homochiral sequences that can be readily cyclized into FcNR s. Meanwhile, when the % ee of FcL is low, the homochiral sequences in -[ FcL -Ag + ] n - must be short and therefore are hardly eligible for spontaneous cyclization. Why were FcNR s formed? Even though the probability is very low, homochiral -[ FcL -Ag + ] n - can be statistically generated and undergo spontaneous cyclization to give FcNR s minutely. We found that FcNR s can be amplified by heterochirally templating their own synthesis using metallophilic interaction. Because of this stereochemical preference, the growth of FcNR s into FcNT s via the template-assisted mechanism occurs only when both ( R,R ) FcL and ( S,S ) FcL are present in the polymerization system.

ConspectusFor optical and electronic applications of supramolecular assemblies, control of the hierarchical structure from nano- to micro- and millimeter scale is crucial. Supramolecular chemistry controls intermolecular interactions to build up molecular components with sizes ranging from several to several hundreds of nanometers using bottom-up self-assembly process. However, extending the supramolecular approach up to a scale of several tens of micrometers to construct objects with precisely controlled size, morphology, and orientation is challenging. Especially for microphotonics applications such as optical resonators and lasers, integrated optical devices, and sensors, a precise design of a micrometer-scale object is required. In this Account, we review the recent progress on precise control of microstructures from π-conjugated organic molecules and polymers, which work as micro-photoemitters and are suitable for optical applications.After the introduction on the importance of the control of the hierarchical structures from molecular assembly, we review supramolecular methodology for assembling molecules and supramolecules to form microstructures such as spheres and polygons with precisely controlled morphology and molecular orientations. The resultant microstructures act as anisotropic emitters of circularly polarized luminescence. We report that synchronous crystallization of π-conjugated chiral cyclophanes forms concave hexagonal pyramidal microcrystals with homogeneous size, morphology, and orientation, which clearly paves the way for the precise control of skeletal crystallization under kinetic control. Furthermore, we show microcavity functions of the self-assembled micro-objects. The self-assembled π-conjugated polymer microspheres work as whispering gallery mode (WGM) optical resonators, where the photoluminescence exhibits sharp and periodic emission lines. The spherical resonators with molecular functions act as long-distance photon energy transporters, convertors, and full-color microlasers. Fabrication of microarrays with photoswitchable WGM microresonators by the surface self-assembly technique realizes optical memory with physically unclonable functions of WGM fingerprints. All-optical logic operations are demonstrated by arranging the WGM microresonators on synthetic and natural optical fibers, where the photoswitchable WGM microresonators act as a gate for light propagation via a cavity-mediated energy transfer cascade. Meanwhile, the sharp WGM emission line is appropriate for utilization as optical sensors for monitoring the mode shift and mode splitting. The resonant peaks sensitively respond to humidity change, absorption of volatile organic compounds, microairflow, and polymer decomposition by utilizing structurally flexible polymers, microporous polymers, nonvolatile liquid droplets, and natural biopolymers as media of the resonators. We further construct microcrystals from π-conjugated molecules with rods and rhombic plates, which act as WGM laser resonators with light-harvesting function. Our developments, precise design and control of organic/polymeric microstructures, form a bridge between nanometer-scale supramolecular chemistry and bulk materials and pave the way toward flexible micro-optics applications.

Optical resonators work as precise physical and chemical sensors. Here, we assemble a whispering gallery mode resonator from a natural polymer, fibroin protein, and successfully observe its catalytic degradation reaction as a spectral shift. This methodology will contribute to the precise in situ observation of biological reactions by optical microscopy.

Organic molecules favour dense packing so that they can maximise the enthalpic gain upon solidification. Multidentate organic molecules that can form reticular bonding networks have been considered essential to overcome this tendency and assemble the molecules in a porous manner. Meanwhile, contrary to this understanding, a few organic molecules have been found to form porous molecular crystals by simply stacking with each other via van der Waals forces or analogous very weak noncovalent interactions. Although the porous molecular crystals were relatively rare in the 2000s due to the difficulty in the synthesis, their number has increased in the last decade, and their functional uniqueness has been unveiled eventually. This article reviews the recent advances in such functional porous molecular crystals. Particularly, thermal stability, processability, structural dynamicity, reactivity, and self-healing ability are highlighted. In addition, fundamental principles behind their functionalities, including the history, energetics, and the effect of crystallization solvent, are also reviewed.

Skeletal or concave polyhedral crystals appear in a variety of synthetic processes and natural environments. However, their morphology, size, and orientation are difficult to control because of their highly kinetic growth character. We report a methodology to achieve synchronous, uniaxial, and stepwise growth of micrometer-scale skeletal single crystals from planar-chiral double-decker molecules. Upon drop-casting of a heated ethanol solution onto a quartz substrate, the molecules spontaneously assemble into standing vessel-shaped single crystals uniaxially and synchronously over the wide area of the substrate, with small size polydispersity. The crystal edge is active even after consumption of the molecules and resumes stereoselective growth with successive feeding. The resultant morphology can be packed into polycyclic aromatic hydrocarbon-like microarchitectures and behaves as a microscopic container.

The mitochondrial gene orf108 , which is co-transcribed with atp1 and causes cytoplasmic male sterility in Brassica crops, is widely distributed across wild species and genera of Brassicaceae. However, to date, intraspecific variations in the presence of orf108 have not yet been studied, and the mechanisms underlying the wide distribution of the gene remain unclear. We analyzed the presence and sequence variations of orf108 in two wild species, Brassica maurorum and Moricandia arvensis . After polymerase chain reaction amplification of the 5' region of atp1 and the coding sequence of orf108 , we determined the DNA sequences. Brassica maurorum and M. arvensis showed variations in the presence of orf108 or orf117 ( orf108 V117 ) both between and within accessions and were not fixed to the mitochondrial type with the male sterile genes. Sequencing of the amplicons showed that B. maurorum had orf108 V117 instead of orf108 . Sequencing also indicated mitochondrial heteroplasmy in the two species; in particular, in B. maurorum , one plant possessed both orf108 and orf108 V117 sequences. These results suggest that substoichiometric shifting of mitochondrial genomes leads to the acquisition or loss of orf108 . Furthermore, fertility restorer genes of the two species were involved in the processing of the mRNA of male sterility genes at different sites.

Dense packing is a universal tendency of organic molecules in the solid state. Typical porous crystals utilize reticular strong intermolecular bonding networks to overcome this principle. Here, we report a solvophobicity-based methodology for assembling discrete molecules into a porous form and succeed in synthesizing isostructural porous polymorphs of an amphiphilic aromatic molecule Py 6 Mes. A computational analysis of the crystal structure reveals the major contribution of dispersion interaction as the driving force for assembling Py 6 Mes into a columnar stacking while the columns are sterically salient and form nanopores between them. The porous packing is facilitated particularly in solvents with weak dispersion interaction due to the solvophobic effect. Conversely, solvents with strong dispersion interaction intercalate between Py 6 Mes due to the solvophilic effect and provide non-porous inclusion crystals. The solvophobicity-directed polymorphism is further corroborated by the polymorphs of Py 6 Mes-analogues, m-Py 6 Mes and Ph 6 Mes., (© 2021. The Author(s).)

A whispering-gallery mode (WGM) optical resonance sensor for volatile organic compounds (VOCs) is developed from polystyrene (PS) microspheres doped with fluorescent β-cyano-appended oligo( p -phenylenevinylene) (β-COPV). The β-COPV-doped PS microspheres (MS COPV ) are formed by the miniemulsion method in a binary solvent. MS COPV expand upon permeation of VOCs into the PS matrix and exhibit a spectral shift of the WGM resonance peak. The permeation efficiency is highly dependent on the chemical affinity between the analyte and the polymer matrix, with exceptionally high selectivity toward aromatic hydrocarbons such as benzene, toluene, and xylenes (BTXs). The high selectivity and sensitivity of MS COPV are in clear contrast to those of conventional WGM sensors that just detect VOCs nonpreferentially through adsorption onto the surface., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

It has long been surmised that the circular polarization of luminescence (CPL) emitted by a chiral molecule or a molecular assembly should vary with the direction in which the photon is emitted. Despite its potential utility, this anisotropic CPL has not yet been demonstrated at the level of single molecules or supramolecular assemblies. Here we show that conjugated polymers bearing chiral side chains self-assemble into solid microspheres with a twisted bipolar interior, which are formed via liquid-liquid phase separation and subsequent condensation into a cholesteric lyotropic liquid crystalline mesophase. The resultant microspheres, when dispersed in methanol, exhibit CPL with a g lum value as high as 0.23. The microspheres are mechanically robust enough to be handled with a microneedle under ambient conditions, allowing comprehensive examination of the angular anisotropy of CPL. The single microsphere is found to exhibit distinct angularly anisotropic birefringence and CPL with g lum up to ∼0.5 in the equatorial plane, which is 2.5-fold greater than that along the polar axis. Such optically anisotropic solid materials are important for the application to next-generation microlight-emitting and visualizing devices as well as for fundamental optics studies of chiral light-matter interaction.

Cytoplasmic male sterility (CMS) observed in many plants leads defect in the production of functional pollen, while the expression of CMS is suppressed by a fertility restorer gene in the nuclear genome. Ogura CMS of radish is induced by a mitochondrial orf138, and a fertility restorer gene, Rfo, encodes a P-type PPR protein, ORF687, acting at the translational level. But, the exact function of ORF687 is still unclear. We found a Japanese variety showing male sterility even in the presence of Rfo. We examined the pollen fertility, Rfo expression, and orf138 mRNA in progenies of this variety. The progeny with Type H orf138 and Rfo showed male sterility when their orf138 mRNA was unprocessed within the coding region. By contrast, all progeny with Type A orf138 were fertile though orf138 mRNA remained unprocessed in the coding region, demonstrating that ORF687 functions on Type A but not on Type H. In silico analysis suggested a specific binding site of ORF687 in the coding region, not the 5' untranslated region estimated previously, of Type A. A single nucleotide substitution in the putative binding site diminishes affinity of ORF687 in Type H and is most likely the cause of the ineffectiveness of ORF687. Furthermore, fertility restoration by RNA processing at a novel site in some progeny plants indicated a new and the third fertility restorer gene, Rfs, for orf138. This study clarified that direct ORF687 binding to the coding region of orf138 is essential for fertility restoration by Rfo.

Donor-acceptor-donor conjugates composed of electron-donating carbon-bridged styrylstilbene (COPV2) and electron-accepting thiadiazole derivatives equipped with carbazolyl (Cz) terminators, Cz-COPV2-A-COPV2-Cz (A = benzothiadiazole (BTz), naphthobis(thiadiazole) (NTz), or benzobis(thiadiazole) (BBTz)), were newly synthesized and found to serve as efficient and stable long-wavelength photoluminescent dyes in organic and aqueous media. In particular, Cz-COPV2-BBTz-COPV2-Cz showed photoluminescence in the near infrared region (895-927 nm) with a photoluminescence quantum yield (PLQY) of up to 0.19 in cyclohexane and of 0.02-0.03 in THF/water mixtures. Its analogues with weaker acceptors, Cz-COPV2-BTz-COPV2-Cz and Cz-COPV2-NTz-COPV2-Cz, showed yellow to deep-red emission in organic solvents, with PLQYs of up to 0.71 in organic solvents and 0.45 in THF/water mixtures., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Depositing minute light emitters into a regular array is a basic but essential technique in display technology. However, conventional lithographic methodologies involve multistep and energy-consuming processes. Here, we develop a facile method in which organic and polymeric fluorescent dyes spontaneously aggregate to form a patterned microarray. We find that a thin film of fluorescent π-conjugated polymer transforms into micrometer-sized aggregates when exposed to binary organic vapor at ambient temperature. The arrayed microaggregates can be formed over the whole substrate surface when using a quartz substrate that is prepatterned with regular hydrophilic boxes and hydrophobic grids. The resultant microarray is applicable to optical memories and displays when photoswitchable fluorophores are doped into the polymer matrix.

In addition to Ogura cytoplasmic male sterility (CMS), which is used extensively for F 1 hybrid seed production in Brassicaceae crops, two other CMS systems, NWB CMS and DCGMS, have also been identified. The causal gene for the latter two CMS systems has been identified as a novel chimeric gene, orf463 . We previously reported that orf463 is specific to black radish cultivars and that it is present in line 'RS-5' of Raphanus raphanistrum ; however, the orf463 sequence in 'RS-5' differed from that of black radish cultivars. Though, R. raphanistrum with an orf463 sequence identical to that found in black radish cultivars was recently identified. We therefore sought to determine whether the orf463 gene in line 'RS-5' induces CMS in radishes. We crossed 'RS-5' as a female parent with a cultivated radish, 'Uchiki-Gensuke', as a male parent, and examined the gross plant morphology and pollen fertility of the resulting progeny. The F 2 population contained both male sterile plants and plants with black roots. The findings showed that R. raphanistrum contains two types of orf463 genes that induce CMS, and that the origin of black radishes could be attributed to R. raphanistrum having orf463 gene., (Copyright © 2020 by JAPANESE SOCIETY OF BREEDING.)

Vapochromic behaviour of porous crystals is beneficial for facile and rapid detection of gaseous molecules without electricity. Toward this end, tailored molecular designs have been established for metal-organic, covalent-bonded and hydrogen-bonded frameworks. Here, we explore the hydrochromic chemistry of a van der Waals (VDW) porous crystal. The VDW porous crystal VPC-1 is formed from a novel aromatic dendrimer having a dibenzophenazine core and multibranched carbazole dendrons. Although the constituent molecules are connected via VDW forces, VPC-1 maintains its structural integrity even after desolvation. VPC-1 exhibits reversible colour changes upon uptake/release of water molecules due to the charge transfer character of the constituent dendrimer. Detailed structural analyses reveal that the outermost carbazole units alone are mobile in the crystal and twist simultaneously in response to water vapour. Thermodynamic analysis suggests that the sigmoidal water sorption is induced by the affinity alternation of the pore surface from hydrophobic to hydrophilic., (© 2020. The Author(s).)

Microcrystallites are promising minute mirrorless laser sources. A variety of luminescent organic compounds have been exploited along this line, but dendrimers have been inapplicable owing to their fragility and extremely poor crystallinity. Now, a dendrimer family that overcomes these difficulties is presented. First-, second-, and third-generation carbazole (Cz) dendrimers with a carbon-bridged oligo(phenylenevinylene) (COPV2) core (GnCOPV2, n=1-3) assemble to form microcrystals. The COPV2 cores align uni/bidirectionally in the crystals while the Cz units in G2- and G3COPV2 align omnidirectionally. The dendrons work as light-harvesting antennas that absorb non-polarized light and transfer it to the COPV2 core, from which a polarized luminescence radiates. Furthermore, these crystals act as laser resonators, where the lasing thresholds are strongly coupled with the crystal morphology and the orientation of COPV2, which is in contrast with the conventional amorphous dendrimers., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Here we report an anomalous porous molecular crystal built of C-H···N-bonded double-layered roof-floor components and wall components of a segregatively interdigitated architecture. This complicated porous structure consists of only one type of fully aromatic multijoint molecule carrying three identical dipyridylphenyl wedges. Despite its high symmetry, this molecule accomplishes difficult tasks by using two of its three wedges for roof-floor formation and using its other wedge for wall formation. Although a C-H···N bond is extremely labile, the porous crystal maintains its porosity until thermal breakdown of the C-H···N bonds at 202°C occurs, affording a nonporous polymorph. Though this nonporous crystal survives even at 325°C, it can retrieve the parent porosity under acetonitrile vapor. These findings show how one can translate simplicity into ultrahigh complexity., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

The complete sequence of the mitochondrial genome was determined for two cultivars of Brassica rapa . After determining the sequence of a Chinese cabbage variety, 'Oushou hakusai', the sequence of a mizuna variety, 'Chusei shiroguki sensuji kyomizuna', was mapped against the sequence of Chinese cabbage. The precise sequences where the two varieties demonstrated variation were ascertained by direct sequencing. It was found that the mitochondrial genomes of the two varieties are identical over 219,775 bp, with a single nucleotide polymorphism (SNP) between the genomes. Because B. rapa is the maternal species of an amphidiploid crop species, Brassica juncea , the distribution of the SNP was observed both in B. rapa and B. juncea . While the mizuna type SNP was restricted mainly to cultivars of mizuna (japonica group) in B. rapa , the mizuna type was widely distributed in B. juncea . The finding that the two Brassica species have these SNP types in common suggests that the nucleotide substitution occurred in wild B. rapa before both mitotypes were domesticated. It was further inferred that the interspecific hybridization between B. rapa and B. nigra took place twice and resulted in the two mitotypes of cultivated B. juncea .

Crop species of Brassica (Brassicaceae) consist of three monogenomic species and three amphidiploid species resulting from interspecific hybridizations among them. Until now, mitochondrial genome sequences were available for only five of these species. We sequenced the mitochondrial genome of the sixth species, Brassica nigra (nuclear genome constitution BB), and compared it with those of Brassica oleracea (CC) and Brassica carinata (BBCC). The genome was assembled into a 232 145 bp circular sequence that is slightly larger than that of B. oleracea (219 952 bp). The genome of B. nigra contained 33 protein-coding genes, 3 rRNA genes, and 17 tRNA genes. The cox2-2 gene present in B. oleracea was absent in B. nigra. Although the nucleotide sequences of 52 genes were identical between B. nigra and B. carinata, the second exon of rps3 showed differences including an insertion/deletion (indel) and nucleotide substitutions. A PCR test to detect the indel revealed intraspecific variation in rps3, and in one line of B. nigra it amplified a DNA fragment of the size expected for B. carinata. In addition, the B. carinata lines tested here produced DNA fragments of the size expected for B. nigra. The results indicate that at least two mitotypes of B. nigra were present in the maternal parents of B. carinata.

Covalent organic synthesis commonly uses the strategy of selective bond cleavage and formation. If a similar approach can be applied stepwisely to noncovalent synthesis, more exotic or challenging nanostructures might become achievable. Here, we report that ferrocene-based tetratopic pyridyl ligands, which can dynamically change their geometry by means of thermal rotation of their cyclopentadienyl rings in solution, assemble with AgBF4 into discrete metal-organic nanotubes with large and uniform diameters. The nanotubes can be cut into metal-organic nanorings through selective attenuation of the inter-nanoring interaction via ferrocene oxidation. The resultant nanorings can be transferred onto inorganic substrates electrostatically or allowed to reassemble to form the original nanotube by the reductive neutralization of their oxidized ferrocene units.

In wheat (Triticum) and Aegilops, chloroplast and mitochondrial genomes have been studied for over three decades to clarify the phylogenetic relationships among species, and most of the maternal lineages of polyploid species have been clarified. Mitochondrial genomes of Emmer (tetraploid with nuclear genome AABB) and Dinkel (hexaploid with AABBDD) wheat are classified into two different types, VIIa and VIIb, by the presence-absence of the third largest HindIII fragment (named H3) in the mitochondrial DNA. Although the mitochondrial genome in the genera often provides useful information to clarify the phylogenetic relationship among closely related species, the phylogenetic significance of this dimorphism has yet not been clarified. In this study, to facilitate analysis using a large number of accessions, a sequence characterized amplified region (SCAR) marker that distinguishes the type VIIb mitochondrial genome from type VIIa was first developed. Mitochondrial genome type was determined for each of 30 accessions of wild and cultivated Emmer wheat and 25 accessions of Dinkel wheat. The mitochondrial genome type for each accession was compared with the plastogroup that had been determined using chloroplast microsatellite markers. Unexpectedly, the distribution of mitochondrial genome type was not in accordance with that of the plastogroups, suggesting occasional paternal leakage of either the mitochondrial or chloroplast genome during speciation and differentiation of Emmer and Dinkel wheat. An alternative possibility that substoichiometric shifting is involved in the observed dimorphism of the mitochondrial genome is also discussed.

Background: Plant mitochondrial genome has unique features such as large size, frequent recombination and incorporation of foreign DNA. Cytoplasmic male sterility (CMS) is caused by rearrangement of the mitochondrial genome, and a novel chimeric open reading frame (ORF) created by shuffling of endogenous sequences is often responsible for CMS. The Ogura-type male-sterile cytoplasm is one of the most extensively studied cytoplasms in Brassicaceae. Although the gene orf138 has been isolated as a determinant of Ogura-type CMS, no homologous sequence to orf138 has been found in public databases. Therefore, how orf138 sequence was created is a mystery. In this study, we determined the complete nucleotide sequence of two radish mitochondrial genomes, namely, Ogura- and normal-type genomes, and analyzed them to reveal the origin of the gene orf138., Results: Ogura- and normal-type mitochondrial genomes were assembled to 258,426-bp and 244,036-bp circular sequences, respectively. Normal-type mitochondrial genome contained 33 protein-coding and three rRNA genes, which are well conserved with the reported mitochondrial genome of rapeseed. Ogura-type genomes contained same genes and additional atp9. As for tRNA, normal-type contained 17 tRNAs, while Ogura-type contained 17 tRNAs and one additional trnfM. The gene orf138 was specific to Ogura-type mitochondrial genome, and no sequence homologous to it was found in normal-type genome. Comparative analysis of the two genomes revealed that radish mitochondrial genome consists of 11 syntenic regions (length >3 kb, similarity >99.9%). It was shown that short repeats and overlapped repeats present in the edge of syntenic regions were involved in recombination events during evolution to interconvert two types of mitochondrial genome. Ogura-type mitochondrial genome has four unique regions (2,803 bp, 1,601 bp, 451 bp and 15,255 bp in size) that are non-syntenic to normal-type genome, and the gene orf138 was found to be located at the edge of the largest unique region. Blast analysis performed to assign the unique regions showed that about 80% of the region was covered by short homologous sequences to the mitochondrial sequences of normal-type radish or other reported Brassicaceae species, although no homology was found for the remaining 20% of sequences., Conclusions: Ogura-type mitochondrial genome was highly rearranged compared with the normal-type genome by recombination through one large repeat and multiple short repeats. The rearrangement has produced four unique regions in Ogura-type mitochondrial genome, and most of the unique regions are composed of known Brassicaceae mitochondrial sequences. This suggests that the regions unique to the Ogura-type genome were generated by integration and shuffling of pre-existing mitochondrial sequences during the evolution of Brassicaceae, and novel genes such as orf138 could have been created by the shuffling process of mitochondrial genome.

Plastid engineering technique has been established only in Nicotiana tabacum, and the widespread application is severely limited so far. In order to exploit a method to transfer the genetically transformed plastomes already obtained in tobacco into other plant species, somatic cell fusion was conducted between a plastome transformant of tobacco and a cultivar of petunia (Petunia hybrida). A tobacco strain whose plastids had been transformed with aadA (a streptomycin/spectinomycin adenylyltransferase gene) and mdar [a gene for monodehydroascorbate reductase (MDAR)] and a petunia variety, 'Telstar', were used as cell fusion partners. An efficient regeneration system from the protoplasts of both the parents, and effectiveness of selection for the aadA gene with spectinomycin were established before the cell fusion. In addition, the influence of UV irradiation on the callus development from the protoplasts and shoot regeneration of tobacco was investigated. Protoplasts were cultured after cell fusion treatment with polyethylene glycol, and asymmetric somatic cybrids were selected using the aadA gene as a marker. Although many shoots of tobacco that had escaped the UV irradiation regenerated, several shoots possessing the morphology of petunia and the resistance to spectinomycin were obtained. Molecular analyses of the petunia type regenerants demonstrated that they had the nuclear and mitochondrial genomes derived from petunia besides the chloroplasts of tobacco transformed with aadA and mdar. Furthermore, it was ascertained that mdar was transcribed in the somatic cybrids. The results indicate the success in intergeneric transfer of transformed plastids of tobacco into petunia.

Depression and anxiety are common psychiatric syndromes in the cancer population, but are not always managed very well due to the barriers to psychiatric consultation in Japan. We have tried to care for cancer patients with depression or anxiety through our psycho-oncology outpatient clinic. We have found that some anxiety in cancer patients derives from miscommunications between patients and physicians in charge because physicians do not tell the conditions of diseases clearly to patients. Needless to say, physicians should learn the communication skills regarding breaking bad news but we would like to emphasize the importance of smooth communication among health care professionals through this case report which makes us reconsider how we should have told the patient the truth (the time for stopping anti-cancer treatment, prognosis and so on) to a patient.

To reveal the molecular and genetic mechanism of fertility restoration in Ogura male sterility in Japanese wild radish (Raphanus sativus var. hortensis f. raphanistroides), we investigated fertility restoration of a plant that lacks the dominant type of orf687, a previously identified fertility restorer gene. A total of 100 F2 plants were made from the cross between a male-sterile strain with the Ogura cytoplasm, 'MS-Gensuke', and a Japanese wild radish plant. Segregation of pollen fertility in the F2 plants led us to assume that 2 dominant complementary genes controlled the fertility restoration of the plants. However, the fertility of 27 of 59 male-fertile plants was not completely restored, resulting in a group of plants with partial male fertility. Northern blot analysis of the CMS-associated gene orf138 indicated that one restorer allele (termed Rft) was involved in the processing of orf138 RNA. Rapid amplification of cDNA ends (RACE) and subsequent Northern blot analysis confirmed that the orf138 transcript lost a 5' part of the coding region of the orf138 gene in the restored plants. The accumulation of ORF138 protein was significantly reduced by Rft, but trace amounts of the protein were recognized in both partially male-fertile and male-sterile plants with Rft. The relationship of pollen fertility and segregation of co-dominant sequence tagged site (STS) markers in the F2 generation suggested that the penetrance of Rft was so low that Rft needs suitable conditions to function sufficiently for the complete restoration of fertility.

Background and Aims: Expression of the mitochondrial gene orf138 causes Ogura cytoplasmic male sterility (CMS) in Raphanus sativus, but little is known about the mechanism by which CMS takes place. A preliminary microarray experiment revealed that several nuclear genes concerned with flavonoid biosynthesis were inhibited in the male-sterile phenotype. In particular, a gene for one of the key enzymes for flavonoid biosynthesis, chalcone synthase (CHS), was strongly inhibited. A few reports have suggested that the inhibition of CHS causes nuclear-dependent male sterile expression; however, there do not appear to be any reports elucidating the effect of CHS on CMS expression. In this study, the expression patterns of the early genes in the flavonoid biosynthesis pathway, including CHS, were investigated in normal and male-sterile lines., Methods: In order to determine the aberrant stage for CMS expression, the characteristics of male-sterile anthers are observed using light and transmission electron microscopy for several stages of flower buds. The expression of CHS and the other flavonoid biosynthetic genes in the anthers were compared between normal and male-sterile types using real time RT-PCR., Key Results: Among the flavonoid biosynthetic genes analysed, the expression of CHS was strongly inhibited in the later stages of anther development in sterility cytoplasm; accumulation of putative naringenin derivatives was also inhibited., Conclusions: These results show that flavonoids play an important role in the development of functional pollen, not only in nuclear-dependent male sterility, but also in CMS.

The heart of animals is regulated through the central nervous system in response to external sensory stimuli. We found, however, that the adult neurogenic heart of the isopod crustacean Ligia exotica has photosensitivity. The beat frequency of the isolated heart decreased in response to a light stimulus. Magnitude of the response was stimulus intensity dependent and the heartbeat frequency decreased to less than 80% of the dark value during illumination of the white light with an intensity of 6.0 mW cm-2. The spectral sensitivity curve of the heart photoresponse peaked at a wavelength around 520 nm. In response to 530 nm monochromatic light, the relationship between light intensity and response magnitude was linear and the threshold intensity was 7.26 x 1012 quanta cm-2 s-1. Bursting activity of the cardiac ganglion, which is located in the heart and acts as the cardiac pacemaker deceased in frequency in response to illumination by white light. This fact suggests that the heart photoresponse of L. exotica results from the photosensitivity of the cardiac ganglion neurons. The photoresponse of the heart therefore contributes to regulation of cardiac output in addition to other regulatory systems.

Hybrid lethality, a type of reproductive isolation, is a genetically controlled event appearing at the seedling stage in interspecific hybrids. We characterized the lethality of F(1) hybrid seedlings from Nicotiana gossei Domin and Nicotiana tabacum cv Bright-Yellow 4 using a number of traits including growth rate, microscopic features of tissues and cells, ion leakage, DNA degradation, reactive oxygen intermediates including superoxide radical (O(2)(-)) and hydrogen peroxide (H(2)O(2)), and expression of stress response marker genes. Lethal symptoms appeared at 4 d after germination in the basal hypocotyl and extended toward both the hypocotyl and root of the plants grown at 26 degrees C. Microscopic analysis revealed a prompt lysis of cell components during cell death. Membrane disruption and DNA degradation were found in the advanced stage of the lethality. The death of mesophyll cells in the cotyledon was initiated by the vascular bundle, suggesting that a putative factor inducing cell death diffused into surrounding cells from the vascular tissue. In contrast, these symptoms were not observed in the plants grown at 37 degrees C. Seedlings grown at 26 degrees C generated larger amounts of reactive oxygen intermediate in the hypocotyl than those grown at 37 degrees C. A number of stress response marker genes were expressed at 26 degrees C but not at 37 degrees C. We proposed that a putative death factor moving systemically through the vascular system induced a prompt and successive lysis of the cytoplasm of cells and that massive cell death eventually led to the loss of the hybrid plant.

Social relations among even-sized male individuals of Odontobutis obscurus, a carnivorous eleotrid goby, were observed in a small experimental population with measurements of individual body size and food intake. 1. Nipping, chasing, threatening, fighting and territorial defence were always observed. The dominance order of an incomplete peck-right type was recognized all the time. The dominant and the second-rank fish widely surpassed other subordinate individuals in the frequency of their attacking behaviour. 2. The dominant fish occupied and defended the whole bottom area of the aquarium (ca. 0.36 m 2 ) as his territory throughout the experimental period except only 1 day, though he was frequently challenged by the second-rank fish. Introducing nest-holes in the aquarium did not cause either increase of territory number or decrease of territory size. The holes were used by the dominant fish as the center of his territory. 3. All individuals increased their body weight in the initial period, but the growth of two subordinate fish became stagnant in the middle stage and later on, resulting in a wider difference between the growth rates of dominant and subordinate groups. 4. The second-rank fish showed the greatest food (live goldfish) intake and the highest gross efficiency of food/growth conversion, and his body weight surpassed that of the dominant fish in the later half of the experimental period. Thus the social ranking did not agree with the body-size ranking. 5. Both kinds of ranking did not change during the following periods of starvation and limited feeding. 6. O. obscurus showed predatory behaviour even at midnight in darkness whenever fed with gold fish, which was followed by a short period of aggressive behaviour.

Population dynamics of two large chironomids, Chironomus plumosus and Spaniotoma akamusi in Lake Suwa were studied through a four-year period from 1967 to 1970. 1. Based on the daily catches of midge by means of light trap, three emergence periods in a year were confirmed in C. plumosus (April-May, June-July and August-October) and only one in S. akamusi (October-November). 2. C. plumosus produces three generations yearly in the littoral region. In the profundal region, however, it usually lacks the second generation and some part of the larvae of the first generation emerges finally in the third emergence period. 3. Larvae of S. akamusi disappeared from the surface layer of mud bottom in May as the result of their burrowing. Pupation and emergence took place after their reppearance at the surface layer in September. 4. In the imagines of C. plumosus trapped through an emergence period, males as a rule predominated over females (males 50-83%). The predominance of males over females was even more striking expressed in S. akamusi (males 83-93%). 5. Population density of larvae of C. plumosus attained its maximum in June (ca. 1200-5400 individuals/m 2 in the profundal region) and in October (ca. 1500 to 2100/m 2 in the same region) with the appearance of newly hatched larvae in the lake bottom. The maximum of biomass appeared either in correspondence to that of population density or a little later, and reached 15-90 and 10-27 g fresh weight/m 2 in the above-mentioned periods respectively. 6. Population density of larvae of S. akamusi reached a maximum (ca. 700 to 4800 individuals/m 2 in the profundal region) in the period from December to March. The maximum biomass was found in March (ca. 10-96 g fresh wt./m 2 ) when the growth of the larvae had been almost completed. 7. Survival rate of wintered larvae of C. plumosus was very low (ca. 6-7%) in 1968 and 1969, whereas it amounted to about 70% in 1970, followed by an unusually intensive emergence. 8. The quantity of pupae produced in an emergence period was estimated based on the numbers of larvae before and after emergence. The total amount of pupae produced per year was estimated at ca. 268-354 tons in C. plumosus and at ca. 10-168 tons in S. akamusi for the whole lake. A certain quantitative relationship was found between the total number of trapped imagines and the estimated number of pupae produced in an emergence period in both species.