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The cDNA library prepared from Lentinula edodes, Hokken 600 (H600), primordia was screened using cDNA expressed specifically in Dictyostelium discoideum prestalk as a probe. Twenty-one clones, Le-Dd1 ~ 21, were isolated from the L. edodes primordia cDNA library. Functional analysis of each gene was carried out by transformation into protoplast cells from L. edodes Mori 252 (M252) mycelia with the overexpression vector pLG-RasF1 of each gene because M252 protoplast cells were transformed with an 11-fold higher efficiency than H600 cells. Transformants with the overexpression vector of Le-Dd10 formed a fruiting body at almost the same time as H600, a positive control, although M252, a negative control, did not form a fruiting body under culture conditions. This suggested that Le-Dd10 is involved in the formation of fruiting bodies. Single-strand conformation polymorphism analysis revealed that Le-Dd10 is located on No. 4 linkage group of L. edodes. The properties of Le-Dd10 products were investigated by Western blotting analysis using polyclonal antibodies against GST:Le-Dd10 fusion proteins. As a result, 56-kDa, 27-kDa, and 14-kDa protein bands appeared in primordial and fruiting body stages, although the expected molecular weight of the Le-Dd10 product was 50 kDa.

The Higo and Manotani high- T metamorphic rocks belong to the Higo terrane, central Kyushu, Japan. This terrane has been suggested as the eastern extension of the North China–South China collision zone based mainly on the similar petrological and geochronological data to the north Dabie high-grade rocks. In this study, detrital zircon U–Pb dating for the Higo metamorphic rocks yielded a maximum depositional age of 197 Ma with a prominent component at 193–284 Ma (62–95%) and a subsidiary peak at 1847–1875 Ma (19–28%); whereas for the Manotani metamorphic rocks, the maximum depositional age is 263 Ma with a prominent component at 263–304 Ma (98%). These results suggest that the protoliths of the Higo and Manotani metamorphic rocks might be equivalent to those of the early–middle Jurassic Chizu and late Triassic Suo high- P metamorphic rocks, southwest Japan, respectively. The absence of middle Neoproterozoic detrital zircon ( c . 700–825 Ma) is incompatible with a proposition that the proto-Japan might have been located close to the South China craton, where Permian–Jurassic sedimentary rocks contain a significant amount of middle Neoproterozoic detrital zircon. The zircon provenance of the Higo terrane, as well as of the Chizu and Suo belts, could therefore be the North China craton, suggesting that the Suo metamorphic rocks, including the Manotani metamorphic rocks, have formed at the subduction plate boundary in the east, which changed into the contemporaneous North China–South China collision plate boundary in the west, likely passing through the Korean Peninsula. The transformation of the Chizu and Suo metamorphic rocks to the Higo and Manotani metamorphic rocks can be accounted for by the oceanward advance of the volcanic arc during trench retreating. The Cretaceous high- T metamorphism and related igneous intrusions of the Higo terrane would be regarded as the initial phase of the Ryoke event.

We applied interface-controlled kinetics, including interface-controlled Ostwald ripening and non-hydrostatic dissolution–precipitation, to metamorphic zircon and phengite growth in a high-pressure (high-P) metamorphic complex. This kinetic modeling yields the growth duration of metamorphic zircon, based on the assumption that dissolution and precipitation of zircon is much slower than that of phengite. The model was applied to zircon and phengite growth in the Nishisonogi unit of the high-P Nagasaki metamorphic complex, western Kyushu, Japan. Given that detrital zircons that are tens of microns in size remain after metamorphism, our model assumption is justified. Our results show that the duration of metamorphic zircon growth in an individual rock ranges from 10 to 20 Myr. In general, the duration of metamorphic zircon growth in the whole Nishisonogi unit is ca. 30 Myr. This prolonged duration implies that high-P metamorphism is sustained by continuous subduction of hydrated oceanic crust and overlying trench-fill sediments. The continuous subduction and accretion of these materials may supply the metamorphic fluid into the high-P metamorphic domain in the deeper part of the accretionary prism, thereby contributing to interface-controlled kinetics in the metamorphic complex.

Metatexite and diatexite migmatites are widely distributed within the upper amphibolite and granulite facies zones of the Higo low-P/high-T metamorphic terrane. Here, we report data from an outcrop in the highest grade part of the granulite facies zone, in which diatexite occurs as a 3 m thick layer between 2 m thick layers of stromatic-structured metatexite within pelitic gneiss. The migmatites and gneiss contain the same peak mineral assemblage of biotite + plagioclase + quartz + garnet + K-feldspar with retrograde chlorite ± muscovite and some accessory minerals of ilmenite ± rutile ± titanite + apatite + zircon + monazite ± pyrite ± zinc sulphide ± calcite. Calculated metamorphic P–T conditions are 800–900 °C and 9–12 kbar. Zircon in the diatexite forms elongate euhedral crystals with oscillatory zoning, but no core–rim structure. Zircon from the gneiss and metatexite forms euhedral–subhedral grains comprising inherited cores overgrown by thin rims. The overgrowth rims in the metatexite have lower Th/U ratios than zircon in the diatexite and yield a 206Pb/238U age of 116.0 ± 1.6 Ma, which is older than the 110.1 ± 0.6 Ma 206Pb/238U age derived from zircon in the diatexite. Zircon from the diatexite has variable REE contents with convex upward patterns and flat normalized HREE, whereas the overgrowth rims in the metatexite and gneiss have steep HREE-enriched patterns; however, both types have similar positive Ce and negative Eu anomalies. 176Hf/177Hf ratios in the overgrowth rims from the metatexite are more variable and generally lower than values from zircon in the diatexite. Based on U–Pb ages, trace element and Hf isotope data, the zircon rims in the metatexite are interpreted to have crystallized from a locally derived melt, following partial dissolution of inherited protolith zircon during anatexis, whereas the zircon in the diatexite is interpreted to have crystallized from a melt that included an externally derived component. By integrating zircon and petrographic data for the migmatites and pelitic gneiss, the metatexite migmatite is interpreted to have formed by in situ partial melting in which the melt did not migrate from the source, whereas the diatexite migmatite included an externally derived juvenile component. The Cretaceous high-temperature metamorphism of the Higo metamorphic terrane is interpreted to reflect emplacement of mantle-derived basalts under a volcanic arc along the eastern margin of the Eurasian continent and advection of heat via hybrid silicic melts from the lower crust. Post-peak crystallization of anatectic melts in a high-T region at mid-crustal depths occurred in the interval c. 116–110 Ma, as indicated by the difference in zircon ages from the metatexite and diatexite migmatites.

High-grade mylonites occur in the Takahama metamorphic rocks, a member of the high-pressure low-temperature type Nagasaki Metamorphic Rocks, western Kyushu, Japan. Mafic layers within the mylonites retain reaction microstructures consisting of margarite aggregates armoring both corundum and kyanite. The following retrograde reaction well accounts for the microstructures in the CaO–Al2O3–SiO2–H2O system: 3Al2O3 + 2Al2SiO5 + 2Ca2Al3Si3O12(OH) + 3H2O = 2Ca2Al8Si4O20(OH)4 (corundum + kyanite + clinozoisite + fluid = margarite). Mass balance analyses and chemical potential modeling reveal that the chemical potential gradients present between kyanite and corundum have likely driven the transport of the CaO and SiO2 components. The mylonitization is considered to take place chronologically after peak metamorphism and before the above reaction, based on the following features: approximately constant thickness of the margarite aggregates, random orientation of margarite, and local modification of garnet composition at a boudin neck that formed during mylonitization. The estimated peak temperature of 640°C and the pressure–temperature conditions of the above reaction indicate that the mylonitization took place at temperature between 530 and 640°C at pressures higher than 1.2 GPa, approximately equivalent to the depth of the lower crust of island arcs.

The Ryoke Metamorphic Complex of the Mikawa Plateau, Central Japan, contains well-preserved geological and thermal structures formed during Cretaceous high-temperature (high- T ) metamorphism. These structures can be explained by a pervasive melt migration model. However, the estimated flux of melt is much higher than that expected for compaction flow of felsic melt. An additional tectonic force and/or melt segregation to network of veins or layers is therefore required. This paper presents the results of numerical modeling of the structural evolution of immiscible viscous fluids under simple-shear deformation, and discusses the role of viscous segregation in enabling pervasive melt flow in hot crust. The results of numerical modeling of simple-shear deformation of immiscible viscous fluids reveal that low-viscosity fluids segregate into lenses and layers. This segregation is a type of viscous segregation that takes place to minimize the dissipation of energy in the system. The rate of energy dissipation is proportional to viscosity. Therefore, this process is expected to occur universally in immiscible viscous fluids with large viscosity contrasts, and is an important process in focusing melt in partially melted rocks. The structures produced by the numerical simulation are similar to those of migmatites. The simulation results suggest that melts distributed randomly in partially melted rock will segregate into lenses or layers with progressive simple-shear deformation. During deformation-enhanced segregation, a melt network will form dynamically. If this process occurs at small to large scales in the hot crust, melts will be effectively transported upward due to buoyancy forces. It is possible that pervasive migmatites at low structural levels within high- T metamorphic complexes may represent “fossil” melt pathways formed by crustal-scale viscous segregation.

For molecular breeding of mushrooms, understanding the mechanism of fruiting body formation by gene expression level is one of vital approaches. To identify the genes controlling traits of fruiting body and determine functions of their genes, the position of candidate genes should be combined with QTL analyses data. As primarily step to analyze the mechanism of fruiting body formation of Lentinula edodes, we located 12 loci containing specifically or abundantly expressed genes during fruiting body formation stage onto a linkage map of L. edodes. Two mapped genes were completely cosegregated from the mfbC gene, and an expressed sequence tag (EST) marker, LEEST359, respectively. In addition, other 2 genes were suggested to be closely located on the genome of L. edodes, because the 2 genes completely cosegregated each other. As a whole, 12 genes isolated from primordia and specifically or abundantly expressed during fruiting body formation were studded all over the genome of L. edodes, and mapped to 8 linkage groups.

In synthetic single crystals of the olivine group, a strong compositional zoning along the growth direction has often been observed. Here we have synthesized large homogeneous single crystals of forsterite doped with manganese (50 mm×150–200 mm) by the Czochralski method using a large volume crucible, at ∼1950 °C in an N 2 atmosphere. The size of the crystals in this study is the largest reported. The homogeneous parts of as-grown crystals with the compositions of (Mn 0.004 Mg 0.996 ) 2 SiO 4 and (Mn 0.011 Mg 0.989 ) 2 SiO 4 are as large as 20×20×50 mm 3 [ x =0.0040±0.0004 in (Mn x Mg 1− x ) 2 SiO 4 ] and 12×12×30 mm 3 [ x =0.011±0.001], respectively. The crystals were prepared to allow for accurate measurements of physical properties and their anisotropies of pure Mn bearing forsterite, to extract the effect of Mn itself, ultimately for the study of the Earth's mantle. The polarized absorption spectra were measured for an evidence of measured anisotropy, and the clear pleochroism was observed.

Detailed reviews of metamorphic thermal structures and spatial distributions of granitic rocks in the high-T Higo metamorphic complex (HMC), central Kyushu, Japan, and Ryoke metamorphic complex in the Yanai district (RMC-Y), southwest Japan, reveal that the high-grade metamorphic rocks were associated with migmatites or syn-metamorphic granitoids. The close association of these rocks suggests that transport and solidification of granitic melts are appreciable heat sources. Partial melting of the pelitic host resists heating of the crust due to its endothermic reaction (i.e. absorption of latent heat). However, the effects of slower thermal evolution produced by partial melting are limited by the boundary conditions assumed for the HMC and RMC-Y. New thermal numerical modeling reveals that the volume fraction of the solidified melt products and the duration of melt migration required for crustal heating to a certain temperature decrease with increasing rates of melt migration. The model predicts that the melt migration rate during formation of the HMC is about three to 10 times higher than that of the RMC-Y, and the corresponding duration of melt migration is about one order of magnitude shorter. The model described here also explains the apparently contradictory observations made in different structural units of the RMC-Y: the metamorphic pressure–temperature (P-T) ratio of the southern unit is higher than those of the central and northern units, even though the volume fraction of granitic rocks in the southern unit is larger. The model suggests that the melt migration rate in the northern and central units was faster than that in the southern unit. Overall, the model implies that variations of metamorphic field P-T arrays and the spatial distributions of granitic rocks in high-T metamorphic complexes may be explained simply by variations in the rate and duration of melt migration in the hot crust.

This paper presents the results of numerical modelling to investigate the regional occurrence of prehnite-bearing metamorphic rocks at shallow levels in subduction zones. The modelling assumes a simple geometrical configuration in which the thermal structure in a prism is controlled by boundary conditions at the top and base of the prism. It is expected that the predominant metamorphic facies in a prism will change with decreasing age of the descending slab. The results of thermal modelling show that the facies boundary between pumpellyite–actinolite and prehnite–actinolite facies (including prehnite–pumpellyite facies) overlaps with an array of P–T conditions in the prism when the age of a descending slab is younger than 10 Myr. This implies that the change of the predominant metamorphic facies from pumpellyite–actinolite to prehnite–actinolite facies will switch drastically. The critical age of the switch depends on subduction parameters. In particular, the critical age of the descending slab is

Brown root rot, caused by Phellinus noxius, leads to problems in management of shade, ornamental, and windbreak trees in subtropical regions of the world, and it has been causing serious problems in Japan since 1988. To identify the pathogenicity, host specialization, and virulence of the pathogen, cross inoculation tests were carried out using isolates of the fungus obtained from nine different tree species. P. noxius was pathogenic to all of the nine tree species tested, and it killed inoculated seedlings. Among the 810 trees inoculated with the fungus, a total of 141 trees (17.4%), including all nine species, were dead within 110 days after inoculation. The first symptom of infection was rapid wilt with discoloration of leaves 20 to 30 days after inoculation, and then the plants quickly declined. Only one isolate of P. noxius that was tested caused significantly higher mortality in its original host than in other species, suggesting that the pathogen has little to no host specificity. However, the fungus did show variation in virulence, with the isolates originating in Bischofia javanica and Casuarina equisetifolia causing significantly higher mortality than those collected from other host species. More isolates of P. noxius from the same host species and/or from various countries should be studied to understand host specialization and virulence of the pathogen.

A suitable screening method for heterozygous DNA markers in shiitake,Lentinula edodes (Berk.) Pegler, is reported. Monokaryons were derived from a dikaryon by de-dikaryotization via protoplast formation. Compatibility of the monokaryons was determined by pairwise culture on agar plates. We selected the primers to amplify polymorphic fragments among the original strain (Hokken600∶H600) and two monokaryons (H600PP-39 and H600PP-67) showing compatibility. A total of 135 fragments were selected as specific random amplified polymorphic DNAs (RAPDs) resulting from 56 primers of the 147 primers tested. Furthermore, we tested whether the polymorphic fragments segregated into 2∶2 among four strains isolated from a basidium. Most of the polymorphic fragments (about 97.8%) showed 2∶2 segregation among the four strains. We concluded that the polymorphic fragments were heterozygous if they were detected in either of the monokaryons (H600PP-39 and H600PP-67) and segregated to 2∶2 among four meiotic strains (H600B-1,-2, -3, and -4). A total of 132 heterozygous DNA markers were therefore selected from a dikaryon of shiitake (Hokken600∶H600).

High-pressure metamorphic rocks are exposed in Karangsambung area of central Java, Indonesia. They form part of a Cretaceous subduction complex (Luk–Ulo Complex) with fault-bounded slices of shale, sandstone, chert, basalt, limestone, conglomerate and ultrabasic rocks. The most abundant metamorphic rock type are pelitic schists, which have yielded late Early Cretaceous K–Ar ages. Small amounts of eclogite, glaucophane rock, garnet–amphibolite and jadeite–quartz–glaucophane rock occur as tectonic blocks in sheared serpentinite. Using the jadeite–garnet–glaucophane–phengite–quartz equilibrium, peak pressure and temperature of the jadeite–quartz–glaucophane rock are P = 22 ± 2 kbar and T = 530 ± 40 °C. The estimated P–T conditions indicate that the rock was subducted to ca 80 km depth, and that the overall geothermal gradient was ∼ 7.0 °C/km. This rock type is interpreted to have been generated by the metamorphism of cold oceanic lithosphere subducted to upper mantle depths. The exhumation from the upper mantle to lower or middle crustal depths can be explained by buoyancy forces. The tectonic block is interpreted to be combined with the quartz–mica schists at lower or middle crustal depths.

This paper presents a theoretical formulation of Ostwald ripening of garnet and discusses the importance of the process during high pressure and low temperature (high P/T) metamorphism. The growth rate of garnet due to Ostwald ripening is formulated for the system consisting of minerals and an intergranular medium. Crystal size distribution (CSD) of garnets are examined and compared with the theoretical distribution for Ostwald ripening. Two types of CSDs are recognized. One is consistent with the theoretical prediction of size distribution while the other is wider than the theoretical distribution. The former CSD applies to samples in which garnets show homogeneous spatial distributions. The latter CSD applies to samples in which garnets show heterogeneous spatial distributions such as in clusters or layers. These relations suggest that the heterogeneity of spatial distributions results in a heterogeneity of concentration of garnet, causing the wide distributions. The mean diameter (dg) has a large variation in samples having narrow distributions. Ostwald ripening explains well the similar patterns of CSD in these samples with different dg because of a scaling law. Compositional profiles of garnets with different size are consistent with Ostwald ripening rather than nucleation and growth kinetics. This suggests that the CSDs result from Ostwald ripening. Magnitude of heating rate will determine which mechanism controls CSD. Nucleation and growth kinetics are dominant when heating rate is large. On the other hand, Ostwald ripening is dominant when heating rate is small. CSDs of garnets in high P/T metamorphic rocks are consistent with the latter case.

Detecting the mating types in shiitake, Lentinula edodes (Berk.) Pegler, is important for making progress in the breeding of this mushroom and determining the compatibility of the pair to cross. Shiitake is a tetrapolar fungus with two unlinking mating factors, A factor and B factor. We screened molecular markers linked to the mating factors using the randomly amplified polymorphic DNA (RAPD) method to develop the mating type identification procedure. Using 147 oligonucleotide primers, a total of 6 linkage markers for the shiitake mating factors, 4 markers for the A factor and 2 markers for the B factor, were discovered with a logarithm of the odds threshold of 3.0 for linkage. Two RAPDs that perfectly segregated with each mating factor among 72 basidiospore strains were detected. Both of these RAPDs were cloned and sequenced to convert them to the sequence characterized amplified region (SCAR) markers. Four primers, two sets of primers, were designed according to the internal sequences of two RAPDs tightly linking to the A factor or B factor. Consequently, we determined the polymerase chain reaction condition for multiplex analyses of these SCAR markers.Key words: Lentinula edodes, SCAR, diagnostic, mating type.

Purified tyrosinase T1 was incubated with neuraminidase. The catalytic activity of tyrosinase was essentially retained, after this treatment. The tyrosinase band (Dopa stained) was transformed into a new less anodic form, similar to tyrosinase T2, on disc electrophoresis. The band of protein was also converted to the same position as the Dopa stained. The other hand, the only one PAS stained band of native tyrosinase T1 was splitted into the three slower-moving bands. One was consistent with Dopa and protein stained bands. The other two were much more slower than the former band and completely free of peptide and enzymic activity. The PAS-densitometric value of native tyrosinase T1 was almost equal to those of three separated bands in total. These results suggest that mammalian tyrosinase is a kind of glycoprotein.

Purified soluble tyrosinase isolated from the melanosomes of Harding-Passey mouse melanoma was incubated with L-dopa. The reaction velocity of the tyrosinase thus incubated decreased significantly. There was an inverse linear relationship between the concentration of dopa in the preincubation mixture and the reaction velocity of the tyrosinase which remained. The experimental results obtained were similar to what had been observed in melanosomes. 64 Cu-exchanged tyrosinase or 11 C-amino-acid-labeled tyrosinase were incubated with L-dopa; the reaction mixture was centrifuged after varied incubation times, and the radioactivity of the obtained supernatant was determined. The time courses of the disappearance of labeled tyrosinase from the reaction systems indicated that soluble tyrosinase combined with the products of the dopa-tyrosinase reaction and precipitated out with them. Thus tyrosinase was excluded from the reaction systems. The experimental results obtained suggest that the decrease of tyrosinase activity is due to the binding of tyrosinase with reaction products, probably at the active site, and to the disappearance of the tyrosinase molecule from the reaction system.

Tyrosinase was solubilized from the 11,000 × g supernatant fraction microsomal and soluble fractions of Harding-Passey mouse melanoma by trypsin digestion and it was partially purified by Sephadex G-100 gel filteration. In contrast to the melanosome fraction, from which only one active tyrosinase could be solubilized, two active components were isolated from the 11,000 × g supernatant fraction, one major faster-eluted component and one minor slower-eluted component. These correspond to T1 and T2 described by Burnett. Both tyrosinases have similar enzyme characteristics, but differ in their isoelectric points. Antiserum was prepared against tyrosinase T1 from melanosomes. This antiserum cross-reacted with both T1 and T2 tyrosinases of the microsomal and soluble fractions in double diffusion plates and immunoelectrophoresis. The precipitin lines produced with T1 or T2 both have tyrosinase activity, which was demonstrated after incubation with L-dopa. These two enzymes have at least one common antigenic peptide sequence at a position remote from the catalytic center.

Rabbit antiserum against purified tyrosinase from melanosomes of Harding-Passey mouse melanoma was obtained. This antiserum cross-reacted completely with the tyrosinase solubilized from B-16 mouse melanoma melanosomes. C57BL mouse hair follicle tyrosinase is also completely inactivated with this antiserum but mushroom tyrosinase is not. By the Ouchterlony technique, Harding-Passey tyrosinase and B-16 tyrosinase give a single precipitin line with this antiserum. These precipitin lines stained dark brown after incubation with L-dopa.

Tyrosinase was dissolved from the melanosome fraction of Harding-Passey mouse melanoma and purified further by Sephadex G-100 gel filtration and DEAE-cellulose column chromatography. The specific activity of the purified preparation was 763 times as high as that of the original melanosome. Tyrosinase thus isolated showed only a single activity in both the electrophoresis of a polyacrylamide gel and a cellulose acetate. The Km value is the same as those of the original melanosome and the smooth-surfaced-membrane. The relationship between particle bound tyrosinase and solubilized tyrosinase is discussed in this paper.

The case is that of a 65 year-old male with reticulosarcomatosis originating from the skin. There were multiple tumors composed of reticulum cells located only in the skin, particularly around the large joints. The entire course of illness was three years and five months, during which period regression by irradiation, recurrence, or new formation of tumors were repeatedly seen. At the end systemic tumor spread not only of the skin but also in various visceral organs including lymph nodes occurred. From histological and electron microscopic examinations repeatedly performed with biopsy materials, and finally with autopsy materials it was ascertained that the tumor cells had become smaller in size with less lymphoid cell infiltration at the terminal stage.

Rate-limiting processes and the degree of disequilibrium during metamorphic mineral growth are key controls on the rate of dehydration and hydration in the Earth’s crust. This paper examines diffusion-controlled growth and the degree of disequilibrium of garnet porphyroblasts in the Tsukuba metamorphic rocks of central Japan. The analyzed porphyroblasts have irregular and branching morphologies with clear diffusional haloes, indicating that they grew in a diffusion-controlled regime. Mathematical analysis shows that the dominant wavelength of the interface of a garnet porphyroblast is dependent on the extent of supersaturation (Δζ), which is an index for the degree of disequilibrium. Using the calculated upper and lower limits of the dominant wavelength, the value of Δζ is estimated to be 0.05 × 10−1–0.16, which corresponds to a Gibbs free energy (ΔG r ) overstep of 0.9–27 kJ per mole of garnet (12 oxygen atoms) and a temperature overstep (ΔT) of 1.7–50 °C. Using the average value of the dominant wavelength, the following results are obtained: Δζ = 0.15 × 10−1, ΔG r = 2.7 kJ per mole of garnet, and ΔT = 5 °C. These values bring into question the importance of diffusion-controlled growth of garnet porphyroblasts, as highly irregular and branching garnet porphyroblasts are rare in most metamorphic belts. After significant overstepping for the nucleation of garnet, the garnet porphyroblasts grow at a high degree of disequilibrium. However, a high degree of disequilibrium under diffusion-controlled growth would be characterized by diffusional instability. The results indicate that garnet porphyroblasts that lack an irregular and branching morphology may grow at a high degree of disequilibrium under interface-controlled growth, provided they are set in a medium where the diffusion and supply of constituent elements are sufficient, such as a sufficient volume of metamorphic fluid.