Development of lateral line organs in leptocephali of the freshwater eel Anguilla japonica (Teleostei,Anguilliformes)

A study of the ontogeny of the lateral line system in leptocephali of the Japanese eel Anguilla japonica reveals the existence of three morphologically different types of lateral line organs. Type I is a novel sensory organ with hair cells bearing a single kinocilium, lacking stereocilia, distributed mainly on the head of larvae, and morphologically different from typical superficial neuromasts of the lateral line system. Its developmental sequence suggests that it may be a presumptive canal neuromast. Type II is an ordinary superficial neuromast, common in other teleost larvae, which includes presumptive canal neuromasts that first appear on the trunk and accessory superficial neuromasts that later appear on the head and trunk. Type III is a very unusual neuromast located just behind the orbit, close to the otic vesicle, with radially oriented hair cells, suggesting that these serve as multiple axes of sensitivity for mechanical stimuli. The behavior of larval eels suggests that the radially oriented neuromasts may act as the sole mechanosensory organ until the ordinary superficial neuromasts develop. The finding that larval eels possess a well-developed mechanosensory system suggests the possibility that they are also capable of perceiving weak environmental mechanical stimuli, like other teleost larvae.     

Characterization of the estrogenic response to genistein in Japanese medaka (Oryzias latipes)

This study was designed to determine the estrogenic effect of the phytoestrogen genistein on several measures of endocrine function in adult Japanese medaka (Oryzias latipes) relative to 17-beta-estradiol. Adult animals of both sexes were exposed to 75, 750 and 30,000 ng/fish (average fish weight equals 0.26 g) of genistein by i.p. injection, with a positive control group treated with 300 ng/fish of 17-beta-estradiol, while a negative control group received a vehicle-only (corn oil) injection. Content of vitellogenin, the yolk glycoprotein made in the liver in response to estradiol stimulation, was measured using Western blots. Circulating estradiol and testosterone levels were measured using a steroid-enzyme immunosorbant assay. The ability of ovaries and testes to synthesize and release estradiol and testosterone was determined by ex vivo incubation of gonads with 25-hydroxycholesterol. Vitellogenin, while induced by 17-beta-estradiol, was not increased in the liver of individuals treated with genistein. In females, genistein treatment at 750 and 30,000 ng increased the estradiol production of ovaries more than the 17-beta-estradiol treatment. In males, genistein treatment resulted in decreased testosterone production from ex vivo testis and a comparable reduction in circulating testosterone level. The changes in vitellogenin, circulating steroids and ex vivo steroidogenesis in medaka in response to genistein are similar to that of 17-beta-estradiol. However, some endpoints are more sensitive to estradiol treatment (vitellogenin), while others are more sensitive to genistein (male testosterone and ovarian estrogenesis).     

Accumulation of Japanese cedar pollen allergen,Cry j 1, in the protein body I of transgenic rice seeds using the promoter and signal sequence of glutelin GluB-1 gene

Recombinant Cry j 1, a Japanese cedar pollen allergen, was produced in rice seeds for potential use for oral immunotherapy. Cry j 1 cDNA was divided into two parts, an N-terminal half and a C-terminal half, and each was fused downstream to glutelin GluB-1 gene containing sequences of the promoter, 5 untranslated region and signal peptide. A gene for green fluorescent protein was also fused to the 3 end of the Cry j 1 fragment. Recombinant Cry j 1 of up to 16.6 g per mg total protein of the seeds was expressed in transgenic rice seeds. Although the recombinant Cry j 1 was expected to be accumulated in protein body II because of the employment of glutelin signal peptide, it was demonstrated to be accumulated exclusively in protein body I. The recombinant Cry j 1 was not shown to react with IgE of allergic patients, indicating the reduction of the risk of anaphylactic reaction. These results demonstrate that the transgenic rice seeds with the recombinant Cry j 1 would be useful for the study of oral immunotherapy.     

Purification and characterization of two soluble acid invertase isozymes from Japanese pear fruit

Two isozymes (AIV I and AIV II) of soluble acid invertase (EC 3.2.1.26) were purified from Japanese pear fruit through procedures including (NH(4))(2)SO(4) precipitating, DEAE-Sephacel column chromatography, Concanavalin A (ConA)-Sepharose affinity chromatography, hydroxyapatite column chromatography and Mono Q HR 5/5 column chromatography. The specific activities of purified AIV I and AIV II were 2670 and 2340 (nkat/mg protein), respectively. AIV I was a monomeric enzyme of 80 kDa, while AIV II may be also a monomeric enzyme, which is easy to be cleaved to 52 kDa and 34 kDa polypeptide during preparation by SDS-PAGE. The Km values for sucrose of AIV I and AIV II were 3.33 and 4.58 mM, respectively, and optimum pH of both enzyme activities was pH 4.5.     

Biochemical evidence for a cGMP-regulated protein kinase in Pharbitis nil

It is known that the level of cGMP is modulated in response to a number of stimuli in plant cells but intracellular events distal to cGMP metabolism are not clear. Cyclic GMP-dependent protein kinase (Pk-G) is a major effector of cGMP action in animals and yeasts. We wanted to determine whether such kinase is present in plant cells. A soluble protein kinase was isolated from seedlings of Pharbitis nil and purified following purification methods including anion-exchange and affinity-chromatography. The enzyme consists of a single polypeptide of M(r) 70 kDa as determined by SDS-PAGE. From conventional modulators only cyclic GMP, when applied in low concentration, was able to accelerate the enzyme activity in the presence of histones. The enzyme autophosphorylated on serine and threonine residues and phosphorylated some substrates only on serine residues. Mixture of histones and histones H2B, H3 were the best phosphate acceptors. The process of autophosphorylation was accelerated by a low concentration of cGMP and reduced by high concentration of this second messenger. Antibodies raised against catalytic domain of animals Pk-G I alpha and beta cross-reacted with protein kinase from Pharbitis nil tissue. These data, taken together, demonstrate the presence of functional enzyme, which activity is regulated by cGMP and allow to classify this protein kinase as a member of the second messenger regulated group of enzymes.     

Mother–infant relationships and maternal estrogen metabolites changes in macaques (<Emphasis Type="Italic">Macaca fuscata,M. mulatta</Emphasis>)

This research assessed mother–infant relationships in rhesus and Japanese macaques living in analogous captive social groups, and monitored changes in the levels of excreted estrogen metabolites during the peripartum period. Each mother–infant pair was focally observed 3 h per week during the first 12 weeks of life of newborns. Fecal samples were collected twice a week from each mother, starting 4 weeks before delivery and ending 4 weeks after delivery. Infant-directed behaviors appeared to be consistently less protective/controlling and more rejecting in rhesus macaques than in Japanese macaques. Estrogen metabolite levels during the perinatal period were, on average, 3-fold higher in Japanese macaques and showed a sharp increase during the last weeks of pregnancy only in the Japanese macaque group. Considering the ecological and behavioral similarities between Japanese and rhesus macaques, the divergence between the two species in the onset and maintenance of maternal behavior was unexpected. This was possibly linked to the difference in the overall body size and life history, and to the striking divergence in estrogen metabolite variation during the peripartum period. Group size, social relationships, and average age of individuals in the two captive groups were not clearly involved in the recorded differences in maternal behavior. Electronic Publication     

Age-related differences in social grooming among adult female Japanese monkeys ( Macaca fuscata)

The present study investigated the influence of dominance rank in combination with kinship on age-related differences in social grooming among adult females in a free-ranging group of Japanese monkeys (Macaca fuscata). Eighty-three adult females were divided into six sub-groups according to age-class (younger: 5–9 years old; middle: 10–14 years old; older: 15–22 years old) and dominance rank (high and low rank). The ratio of the number of unrelated females that each female groomed to the total number of available unrelated females and grooming bouts which she gave to unrelated females decreased with increasing age for both high- and low-ranking females, whereas age did not appear to affect corresponding values for related females. On the other hand, compared with low-ranking females, high-ranking females of all age-classes received grooming more often from a larger number of unrelated females. Moreover, older females of low rank received grooming less often from a smaller number of unrelated females than younger females of low rank. These results indicate that with increasing age females are more likely to concentrate on related females when they have grooming interactions with other females. This tendency seems to be more apparent for low-ranking females. Moreover, the present findings also indicate that older high-ranking females could maintain their social attractiveness as high as younger high-ranking females.     

The first isolation of two types of trifluoroleucine resistant mutants of Saccharomyces servazzii

Saccharomyces servazzii plays a crucial role in the making of Japanese radish pickles. To make more flavorsome pickles, we sought to generate trifluoroleucine-resistant mutants of S. servazzii. The three resulting mutants could be classified into two types: one that produces more isoamyl alcohol than the parental strain, and one that produces less. The first type has been well documented in Saccharomyces cerevisiae but the latter appears to be novel and has been characterized as such.     

Matrilineal Cohesion and Social Networks in Macaca fuscata

In a provisioned troop of Japanese macaques (Macaca fuscata) in Arashiyama, Japan, greater adherence to Kawamura's rules of matrilineal rank inheritance and youngest ascendancy occurred among high-ranking females versus low-ranking females. Accordingly, high-ranking females formed more clustered hierarchies and low-ranking females had more dispersed hierarchies. A proximate explanation for this finding may be related to differences in how females maintain their social networks. To determine whether the clustering in the hierarchy was reflected in patterns of social cohesiveness, I compared network sizes of coalition and grooming partners for females in each third of the hierarchy. I calculated the proportion of available partners that were coalition and grooming partners within each category of relatedness (0.5 r 0.004 and r = 0). High-ranking females formed coalitions with a large proportion of their close relatives and a small proportion of their distant relatives; middle-ranking females supported an intermediate proportion of their close relatives and a small proportion of their distant relatives; and, low-ranking females formed coalitions with very few available close and distant relatives. High-ranking females groomed nearly all available close relatives and an intermediate proportion of distant relatives, whilst middle- and low-ranking females groomed a large proportion of available close relatives and a very small proportion of distant relatives. Thus, levels of clustering within the hierarchy appeared to reflect levels of social cohesion, in terms of grooming and coalition formation.     

Cytochrome P450 enzyme activity in five herbivorous,non-passerine bird species

We examined hepatic cytochrome P450 activity in wild and hand-reared grey partridges (Perdix perdix), capercaillies (Tetrao urogallus) and ring-necked pheasants (Phasianus colchicus), as well as the enzyme activity in a variety of tissues of hand-reared Japanese quails (Coturnix coturnix japonica) and pigeons (Columba livia). Post-mortem decrease in hepatic enzyme activity in the grey partridge was measured. Hepatic 7-ethoxyresorufin-O-deethylase activity was similar in wild and hand-reared grey partridges and pheasants, but the activity was significantly lower in wild than in hand-reared capercaillies, probably resulting from their phenolic-rich diet. In the tissues of both quails and pigeons 7-ethoxycoumarin-O-deethylase exhibited the highest and 7-pentoxyresorufin-O-deethylase the lowest activity. Hepatic enzyme activity was significantly higher than that in other tissues. In the small intestine some activity could be found, reflecting some intestinal detoxication capacity. Enzyme activity decreased by 34-69% during the 30-min sampling period, which confirmed the importance of equalising sampling time to obtain comparable data. Because the hand-reared birds in this study were fed the same commercial diets, we assumed that the enzyme activity values detected reflect species differences without any induction by dietary secondary compounds.