Permuted tRNA genes expressed via a circular RNA intermediate in Cyanidioschyzon merolae

A computational analysis of the nuclear genome of a red alga, Cyanidioschyzon merolae, identified 11 transfer RNA (tRNA) genes in which the 3' half of the tRNA lies upstream of the 5' half in the genome. We verified that these genes are expressed and produce mature tRNAs that are aminoacylated. Analysis of tRNA-processing intermediates for these genes indicates an unusual processing pathway in which the termini of the tRNA precursor are ligated, resulting in formation of a characteristic circular RNA intermediate that is then processed at the acceptor stem to generate the correct termini.     

Abstracts of nippon Dojyohiryogaku Zasshi

Color change of city refuse during composting process was investigated according to the methods of measurement for color of materials based on the CIE 1931 Standard Colorimetric System. Stimulus value Y (the degree of lightness) and chromaticity coordinates (x, y) were determined with Color Analyzer by measuring relative spectral reflectance. Stimulus value Y of city refuse decreased during composting process, but chromaticity coordinates (x, y) scarcely changed.

Color of various composts, which were produced from city refuse, straw, hog fecal wastes, tree bark, and tree bark mixed with activated sludge, were also investigated by measuring relative spectral reflectance. The shapes of the reflection spectra of city refuse were different from those of the other composts. Colors of the various composts were similar to each other when specified according to their three attributes: value, hue, and chroma (Munsell renotation).

While city refuse was rotting and maturing, stimulus value Yand C/N ratio equally decreased. A positive correlation was found between stimulus value Y and C/N ratio. It was concluded that stimulus value Y can be used as a criterion for determining the degree of maturity of city refuse compost.

The correlation between stimulus value Y and C/N ratio of various composts was also investigated. According to the position on the two coordinates having stimulus value Y and C/N ratio as axe s, various composts were classified into three groups: (i) city refuse compost group, (ii) straw compost group, and (iii) tree bark compost group.     

A novel genotyping technique for distinguishing between Flavobacterium psychrophilum isolates virulent and avirulent to ayu, Plecoglossus altivelis altivelis (Temminck & Schlegel)

We developed a simple genotyping method for Flavobacterium psychrophilum for analysing two single nucleotide polymorphisms (SNPs) in the gyrA gene and to distinguish between isolates that are virulent and avirulent to ayu, Plecoglossus altivelis altivelis (Temminck & Schlegel). The genotyping method is an on/off switch assay and is based on the polymerase chain reaction technique with phosphorothioated primers. We classified 232 isolates from four families of fish (i.e. Plecoglossidae, Osmeridae, Cyprinidae and Salmonidae) into four genotypes (G‐C, A‐T, A‐C and G‐T). The G‐C type isolates exhibited strong pathogenicity to ayu, whereas the A‐T and G‐T types did not show any pathogenicity to this species. The A‐C type exhibited no or weak pathogenicity to ayu. These results indicate that genotyping F. psychrophilum isolates with two SNPs from gyrA can clearly distinguish between isolates potentially harmful to ayu (G‐C type) and those that are potentially not harmful or less harmful (A‐C, A‐T and G‐T type). The on/off switch assay provides a quick, simple, and very powerful DNA genotyping technique for F. psychrophilum isolates.     

Ploidy variation of hardy kiwifruit (Actinidia arguta) resources and geographic distribution in Japan

Survey on the wild genetic resources of hardy kiwifruit (Actinidia arguta) in Japan was conducted to determine the ploidy variation and its geographic distribution. Among the 127 wild plants collected from different geographic locations, 15 plants were diploid, 87 were tetraploid, and 22 were hexaploid. Additionally, 2 plants were heptaploid and one plant was octaploid. The tetraploid plants were distributed all over the country, whereas the diploid and hexaploid plants were geographically localized, in the warm Pacific hill areas of the south western part and in the deep-snow region of the mid-northern part of Honshu, respectively. The diploid plants could be clearly distinguished from other plants with ploidy variation by the morphological characteristics of the leaf and fruit. Hexaploid plants showed a relatively larger L/D ratio of the leaf blade, a greenish petiole, and pubescence on the petiole and lower leaf vein, whereas the tetraploid plants exhibited a reddish petiole and callose hairs on the vein of the lower leaf surface. Fruit shape of the tetraploid plants varied largely, from round to ellipsoidal, whereas that of the hexaploid plants was mostly ellipsoidal. These results indicate that the hexaploid plants of A. arguta as well as the diploid and tetraploid ones, naturally grow in a certain size of population in the restricted region of Japan.     

Deodorization with ku-ding-cha containing a large amount of caffeoyl quinic acid derivatives

Caffeoyl quinic acid (CQA) derivatives in ku-ding-cha, mate, coffee, and related plants were determined by HPLC. One ku-ding-cha contained a large amount of 3,5-dicaffeoylquinic acid (3,5-diCQA, 10.6% in dry weight) as well as 3-CQA (1.7%), 4-CQA (1.1%), 5-CQA (6.3%), 3,4-diCQA (1.8%), and 4,5-diCQA (4.3%). In this ku-ding-cha, the total caffeic acid moiety was 90.3 mmol/100 g of dry weight. The leaves of Ilex latifolia, which is one original species of ku-ding-cha, and another plant of the same genus, I. rotunda, also contained 3,5-diCQA (9.5 and 14.6%), 3-CQA (4.3 and 1.9%), and 5-CQA (4.8 and 3.8%), respectively, whereas raw coffee bean contained 5.5% 5-CQA and other low CQA derivatives. 3,5-DiCQA and 5-CQA with an apple acetone powder (AP) containing polyphenol oxidase showed high capturing activities toward thiols, and two addition compounds between 3,5-diCQA and methane thiol were also identified. Ku-ding-cha indicated extremely strong capturing activities toward methanethiol, propanethiol, and 2-propenethiol in the presence of apple AP. Furthermore, drinking ku-ding-cha reduced the amount of allyl methyl sulfide gas, well-known to persist as malodorous breath long after the ingestion of garlic.     

Intracerebroventricular injection of glucagon-like peptide-1 decreases monoamine concentrations in the hypothalamus of chicks

1. We measured the concentrations of dopamine (DA), norepinephrine (NE), epinephrine (E) and 5-hydroxytryptamine (5-HT) in the hypothalamus of 21-d-old male brown-egg layer-type chicks after intracerebroventricular injection of glucagon-like peptide-1 (GLP-1). 2. The monoamine concentrations of the whole hypothalamus, paraventricular nucleus and lateral hypothalamic area were not significantly affected by GLP-1. 3. However, concentrations of DA, NE and E, but not 5-HT, in the ventromedial hypothalamic nucleus (VMH) were significantly decreased by GLP-1. 4. These observations suggest that the anorexigenic effect of GLP-1 involves catecholaminergic systems in the VMH in the chick.     

Spontaneous early-onset glomerulonephritis in a 8-week-old male Crj:CD1 (ICR) mouse

Glomerular lesions including membranoproliferative glomerulonephritis occur spontaneously in aged mice, but they are rare in young animals. In our laboratory, spontaneous glomerulonephritis was observed in an 8-week-old male Crj:CD1 (ICR) mouse. Macroscopically, the bilateral kidneys were discolored, but no edema or ascites was observed. Glomerular lesions were characterized by a thickening of capillary walls, a double-contoured basement membrane and mesangial expansion due to increased amounts of matrix. Ultrastructurally, mesangial interposition in the capillary wall and subendothelial deposition of basement membrane-like material were observed. No evidence of immune complex deposition or amyloid was found. On the basis of the observed clinical pathology and histopathology, a secondary form of glomerular lesion was excluded. The glomerular lesion was compatible with glomerulonephritis in a young Crj:CD1 (ICR) mouse.     

Mercaptan-capturing properties of mushrooms.

Mercaptan-capturing properties of 33 kinds of mushrooms were measured. The mushrooms having a high capturing ability toward methyl mercaptan (MeSH) were Agaricus bisporus, A. campestris, Boletus fraternus, B. subvelutipes, Gyrodon lividus, Leccinum scabrum, Suillus grevillei, Morchella esculenta, Russula nigricans, Hypholoma sublateritium, and Lyophyllum sykosporum. These are liable to change their color when injured. The mixture of their acetone powders, which contain polyphenol oxidases, and phenolic compounds such as tyrosine, gamma-L-glutaminyl-4-hydroxybenzene (GHB), DOPA, variegatic acid, grevillin B and C, and pigments, and fluorescent compounds from H. sublateritium also showed high MeSH-capturing properties. 2,5-Bis(methylthio)-DOPA was isolated from the reaction mixture of tyrosine and MeSH with tyrosinase, and the existence of 2- and 5-methylthio-DOPAs was also suggested. Furthermore, acetone powders from fruits and vegetables oxidized the above diphenolic compounds to bind MeSH.     

Individual and combined effects of aflatoxin and gizzerosine in broiler chickens

1. The individual and combined effects of aflatoxin B₁ (AFB₁) and DL‐gizzerosine (GIZZ) in growing broiler chickens were investigated in a 7‐d fully randomised trial consisting of 7 dietary treatments (1 and 4 mg GIZZ/kg, 0.66 and 3 mgAFB₁/kg, the combinations 1 mg GIZZ/kg/0.66 mg AFB₁/kg and 4 mg GIZZ/3 mg AFB₁/kg, and a control basal diet without GIZZ or AFB₁).

2. Dietary GIZZ at 1 mg/kg caused moderate gizzard erosions without affecting performance, whereas 4 mg/kg GIZZ induced severe erosion, ulceration and perforation of the gizzard, and significantly affected performance.

3. Dietary AFB₁ at 0.66 or 3 mg/kg did not induce lesions in the gizzard or cause any adverse effects on chick performance.

4. No apparent toxicologic interaction was observed between AFB₁ and GIZZ when they were given simultaneously at relatively low dietary concentrations (0.66 mg/kg AFB₁ + 1 mg/kg GIZZ). However, at higher dietary concentrations (3 mg/kg AFB₁ + 4 mg/kg GIZZ), AFB₁ potentiated the lethality of GIZZ.

5. The combination 3 mg/kg AFB₁/4 mg/kg GIZZ was more toxic than the same concentrations of single toxins and may pose a greater economic threat to the poultry producer than either toxin individually.