DNA synthesis as related to the reappearance of "light interruption rhythm" in a long-day duckweed, Lemna gibba G3

DNA synthesis in the light perturbation period and its relationto the reappearance, due to light perturbation, of once faded-out"light interruption rhythm" in a long-day duckweed, Lemna gibbaG 3, were studied. After long continuous darkness, the duckweedincorporated ³H-thymidine into both nuclear and satellite DNA_sunder a light condition, but into satellite DNA alone undera dark condition. The number of dividing cells in frond epidermisincreased in proportion to the length of the light perturbationperiod. This increase was inhibited by 5-fluorodeoxyuridine.From these and previous results we conclude that nuclear DNAnewly synthesized in the light is intimately related with thereappearance of the rhythm. (Received June 15, 1970; )     

Isolation and characterization of polymorphic microsatellite DNA markers in the Japanese eight‐barbel loach,Lefua echigonia

We isolated and characterized 17 polymorphic microsatellite loci for the Japanese eight‐barbel loach, Lefua echigonia, an endangered freshwater species in streams including agricultural canals in Japan. The number of observed alleles for each locus ranged from two to nine, and the values of observed and expected heterozygosities ranged from 0.125 to 0.844 and from 0.148 to 0.876, respectively. All loci conformed to Hardy–Weinberg equilibrium. Genetic linkage disequilibrium analysis between all pairs of the loci showed no significant departure from the null hypothesis between any of the loci.     

ENZYME ACTIVITIES ASSOCIATED WITH RIBOSOMES FROM SOYBEAN SEEDLINGS

Ribosomes from cotyledons of soybean seeds soaked overnightin water (resting-cotyledon ribosomes) and respective ribosomesfrom cotyledons (working-cotyledon ribosomes) and hypocotyls(hypocotyl ribosomes) of 5 day-old seedlings were prepared.These ribosomes mainly consisted of 80 S particles. However,hypocotyls contained 115 S particles in a small amount and working-cotyledonscontained 115 and 150 S particles which may correspond to thepolymers of ribosomes or polysomes. The abundant 80 S ribosomeswere fractionated by the sucrose density gradient centrifugation,and enzyme activities in the fractionated ribosomes were estimated.RNase, PDase, acid phosphatase, 5'-nucleotidase, XTPase, peroxidaseand ß-glucosidase were found in the ribosomes. Theenzyme activities were lower in the resting-cotyledon ribosomesand higher in the hypocotyl ribosomes. Working-cotyledon ribosomesshowed the middle of them. All these enzymes were also foundin the cytoplasmic solution (supernatant) of cotyledon and hypocotylcells. However, RNase, PDase, 5'-nucleotidase and peroxidasewere concentrated in ribosomes, and the specific activitiesof 5'-nucleotidase and ß-glucosidase were increasedby washing the ribosomes. The status of the enzymes found inthe ribosomes was discussed. (Received May 12, 1966; )     

FLAVOPROTEINS IN THE LEAVES OF HIGHER PLANTS CATALYZING THE OXIDATION OF L-GLUTAMATE

1. Two forms of enzyme capable of catalyzing the oxidation of L-glutamate(and L-aspartate) were isolated from the leaves of spinach andseparated from each other by column-chromatographic purificationon calcium phosphate and anion exchangers. They were distinguishedas GD₁ (L-glutamate dehydrogenase 1) and GD₂ (L-glutamate dehydrogenase2). The purification procedures and some fundamental propertiesof the partially purified enzymes were investigated.
2. It wasdiscovered that the enzymes did not require any cofactor,ie., neither dialysis nor precipitation with ammonium sulfatecaused a fall in enzyme activities and the addition of DPN andTPN to the reaction mixture did not accelerate the reactionrate
3. From the results of spectroscopic investigation GD₁ andGD₂were shown to be flavoproteins, although their prostheticgrouphas not yet been identified The activity of GD₁ was enhancedby the addition of FAD or FMN, while GD₂ was not acceleratedby these factors.
4. The characteristics of the two enzymes includingsubstrate specificity,MICHAELIS constant, optimum pH of thereaction and specificityfor electron acceptors were compared.
5. From the stoichiometric study of the oxidation of L-glutamatewith these enzymes, it was confirmed that the reaction is representedby the following equation: L-glutamate+oxidized dye+h₂o
6. Among various inhibitors tested,molecular oxygen which couldfunction as electron acceptor ofL-glutamate oxidation in thepresence of GD₁ was found to causea strong inhibition uponthe same reaction with TTC as el acceptor.The inhibition wasconfirmed to be due to hydrogen peroxideproduced as a resultof the aerobic oxidation of L-glutamate.

(Received July 25, 1962; )     

Reductive carboxylation and amination of keto acids by spinach chloroplasts

1. In spinach chloroplasts, the occurrence of malic enzyme,isocitrate dehydrogenase, glutamate dehydrogenase and alaninedehydrogenase was confirmed. 2. In the presence of ammonia, pyruvate and -ketoglutarate andpyruvate were photoreductively aminated to glutamate and alanine,respectively. 3. In the absence of ammonia, pyruvate and -ketoglutarate werephotoreductively carboxylated to malate and isocitrate, respectively. 4. Photoreductive carboxylation of pyruvate and -ketoglutaratewas suppressed by molecular oxygen. Inhibition was partly dueto oxidation of photoreduced NADP or NAD. (Received August 4, 1969; )     

Amino-acid Sequence of λ Phage Endolysin

WE wish to present a preliminary report of the amino-acid sequence of λ endolysin. This protein is a lytic enzyme¹ and its structural gene, R, maps toward the right end of λ DNA². Conditional mutants as well as frame-shift mutants (R. Thomas, personal communication) have been isolated and analysed³. Hogness et al.⁴ developed a technique to assay the gene activity of the fragmented λ DNA, which suggested that it might be possible to isolate a small segment of DNA containing the endolysin gene. Purification, immunological properties and end group analysis of λ endolysin were studied by Black and Hogness^5–7.     

Prothoracicotropic Hormone Bioassay: Pupal-Adult Bombyx Assay

Blockage of adult development by brain removal and its resumption by application of the prothoracicotropic hormone (PTTH) were studied using pupae of a racial hybrid J-122 × C-115 of Bombyx mori . A log-linear dose-response relationship was obrained after injection of a PTTH solution. The Bombyx -unit of PTTH has been defined from this dose-response curve.     

A redescription of Cythere japonica Hanai, 1959 (Podocopida: Ostracoda)

Cythere japonica was proposed by Hanai (1959) as a new species of the genus Cythere , from the Pleistocene Sawane Formation in Sado Island, Niigata Prefecture, Japan. The characters of carapace were already known, but the appendages have not been previously described. The authors formerly considered that this species should be separate from the genus Cythere sensu stricto because it has twice as many sieve-type pore systems as typical Cythere species, and a markedly higher carapace. The existence of living Cythere japonica in the tidal zone of north-west Japan is confirmed, and its taxonomic position re-examined on the basis of its appendages and the ontogeny of pore systems. The appendages, except for the copulatory organ, are almost identical with those of other Cythere species, and their pore systems share the same pattern in and before the A-4 moult stage. On the basis of these features this species should be retained in the genus Cythere. Phylogenetic relationships are considered on the basis of the ontogeny of pore systems.
The abdominal segments of podocopid Ostracoda, which have always been regarded as difficult to observe because of their fusion, are shown clearly by the SEM.     

Additive apportioning of lepidopteran and coleopteran species diversity across spatial and temporal scales in a cool–temperate deciduous forest in Japan

Abstract.  1. Forest entomofauna retain high diversity, and examining beta diversity, or species turnover, among assemblages in a forest community is vital to elucidate the source of this diversity.
2. Under the DIVERSITAS in Western Pacific and Asia–International Biodiversity Observation Year (DIWPA–IBOY) project for simultaneously documenting biodiversity throughout the Western Pacific and Asian Region, 892 lepidopteran species (51 742 specimens) and 355 coleopteran species (11 633 specimens) were collected in 2001 by light traps in a cool–temperate forest in northern Japan.
3. This study evaluated the beta diversity of lepidopteran and coleopteran communities by ecological categories (i.e. trap location, forest strata, sampling days, and months), and assessed the habitat preferences of lepidopteran and coleopteran species.
4.  anova -like additive apportioning models were used to quantify the beta diversity among the categories. The models simultaneously provide assessments of whether species distributions are biased in favour of particular habitats.
5. Significantly high beta diversity was observed among months for both Lepidoptera and Coleoptera. The category of months corresponded fairly well to the number of specialist species detected in the category, although a remarkably large number of significant specialists in Coleoptera were observed on strata.
6. The high beta diversity and number of specialist species among strata in both communities indicate that stratification between canopy and ground, and seasonal variation, played major roles in species composition and the rich entomofauna in the forest. Highly mobile adults were influenced by the vertical spatial scale, as previously suggested for larvae.