Identification of quantitative trait loci for flowering-related traits in the D genome of synthetic hexaploid wheat lines

The gene pool of Aegilops tauschii, the D-genome donor of common wheat (Triticum aestivum L.), can be easily accessed in wheat breeding, but remains largely unexplored. In our previous studies, many synthetic hexaploid wheat lines were produced through interspecific crosses between the tetraploid wheat cultivar Langdon and various A. tauschii accessions. The synthetic hexaploid wheat lines showed wide variation in many characteristics. To elucidate the genetic basis of variation in flowering-related traits, we analyzed quantitative trait loci (QTL) affecting time to heading, flowering and maturity, and the grain-filling period using four different F₂ populations of synthetic hexaploid wheat lines. In total, 10 QTLs located on six D-genome chromosomes (all except 4D) were detected for the analyzed traits. The QTL on 1DL controlling heading time appeared to correspond to a flowering time QTL, previously considered to be an ortholog of Eps-A ^m 1 which is related to the narrow-sense earliness in einkorn wheat. The 5D QTL for heading time might be a novel locus associated with wheat flowering, while the 2DS QTL appears to be an allelic variant of the photoperiod response locus Ppd-D1. Some of the identified QTLs seemed to be novel loci regulating wheat flowering and maturation, including a QTL controlling the grain filling period on chromosome 3D. The exercise demonstrates that synthetic wheat lines can be useful for the identification of new, agriculturally important loci that can be transferred to, and used for the modification of flowering and grain maturation in hexaploid wheat.     

Anaphylaxis after rabies vaccination for dogs in Japan

Severe adverse reactions after rabies vaccination in dogs were examined from 317 cases reported to the Ministry of Agriculture, Forestry and Fisheries (MAFF) in Japan during 15-year period from April 2004 to March 2019. We found that 109 of the 317 dogs showed anaphylaxis (0.15/100,000 vaccinated dogs), and 71 of the 109 cases of anaphylaxis resulted in death (0.10/100,000 vaccinated dogs). We measured bovine serum albumin (BSA) in four commercially available rabies vaccines and found the levels ranged from 0.1 to 16.6 µg/dose. Our survey showed that the rate of anaphylaxis to rabies vaccines in dogs is rare, although some cases of anaphylaxis resulted in death. Veterinarians should be well prepared to deal with vaccine-associated anaphylaxis.     

Effect of estrus synchronization treatment after luteolysis on Holstein heifers as embryo transfer recipients

This study was designed to evaluate the effect of estrus synchronization treatments on recipient heifers for embryo transfer (ET). Holstein heifers were separated into the following three groups: (i) an administration of 50 µg GnRH (gonadotropin‐releasing hormone) analog was given to heifers at a random stage of the estrus cycle, followed 7 days later by two administrations of 7.5 mg prostaglandin F2 alfa analog (PG) as control; (ii) another administration of 100 µg GnRH was given to the control group at 48 h after the administration of PG as the second GnRH group; and (iii) an administration of 0.75 mg estradiol benzoate (E2) was given to the control group at 24 h after the administration of PG as the E2 group. Each method caused estrus synchronization. Fresh embryos were nonsurgically transferred into the suitable recipients that had a functional corpora lutea (CL) 7 days after estrus. The E2 group showed a significantly higher (P < 0.01) rate of estrus synchronization (98.9%) at 1–3 days after PG administration and the final pregnancy rate of the E2 group (50.6%) was also significantly higher than the other groups (37.1%, P < 0.05 and 30.9%, P < 0.01, respectively). These findings demonstrate that E2 administration 24 h after PG protocol is effective for estrus synchronization of Holstein heifers, thus improving the productivity of ET.     

Expression analysis of an α‐1, 3‐galactosyltransferase,an enzyme that creates xenotransplantation‐related α–Gal epitope,in pig preimplantation embryos

α‐1,3‐Galactosyltransferase (α‐GalT), an enzyme creating Galα1‐3Gal (α‐Gal) epitope on the cell surface in some mammalian species such as pigs, is known to be a key factor that causes hyperacute rejection upon transplantation from pigs to humans. To establish the RNA interference‐based suppression of endogenous α‐GalT messenger RNA (mRNA) synthesis in porcine preimplantation embryos, we determined the suitable embryonic stage at which stage such approach is possible by using the semi‐quantitative RT‐PCR (qRT‐PCR) and the cytochemical method using a fluorescence‐labeled Bandeiraea simplicifolia Isolectin B₄ (BS‐I‐B₄). Staining with BS‐I‐B₄ demonstrated that α‐Gal epitope expression was first recognized at the 8‐cell stage, and increased up to the hatched blastocyst stage. Single embryo‐based qRT‐PCR also confirmed this pattern. These results indicate that creation of α‐Gal epitope is proceeded by de novo synthesis of α‐GalT mRNA in porcine preimplantation embryos with peaking at the blastocyst stage.     

Purification and characterization of sulfotransferase specific to O-22 of 11-hydroxy saxitoxin from the toxic dinoflagellate Gymnodinium catenatum (dinophyceae)

ABSTRACT: A novel sulfotransferase (O-ST), which transferred the sulfate group of 3'-phosphoadenosine 5'-phosphosulfate (PAPS) to O-22 of 11-α,β-hydroxy saxitoxin (STX) and produced GTX2 + 3, was purified to homogeneity from the cytosolic fraction of clonal-axenic vegetative cells of the toxic dinoflagellate Gymnodinium catenatum GC21V. After four purification steps, including affinity chromatography and anion exchange chromatography, the enzyme was purified 500-fold and the yield was 4%. On affinity chromatography with a PAP-agarose column, O-ST was observed in the bound fraction, and N-ST specific to N-21 of STX and GTX2 + 3 was found in the unbound fraction. The molecular mass of the purified enzyme was determined by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) to be 65 kDa. Gel filtration chromatography showed a native molecular mass of 67 kDa, indicating that O-ST is a monomeric enzyme. The enzyme was optimally active at pH 6.0 and 35°C. O-ST did not require metal cations for its activity. O-ST required PAPS as the sole source of sulfate. O-ST transferred a sulfate group from PAPS to only O-22 of 11-α,β-hydroxy STX and not to N-21 of these toxins. These observations suggested that two ST, N-ST and O-ST, participate in the sulfation of PSP toxins.     

Transferase activity of GhCesA2 (putative cotton cellulose 4- β -glucosyltransferase) expressed in Pichia pastoris

GhCesA2 is a cotton (Gossypium hirsutum) homologue of the bacterial cellulose synthase gene that encodes cellulose 4--glucosyltransferase. The central catalytic region of GhCesA2 was expressed as a soluble protein in the methylotrophic yeastPichia pastoris. The molecular size of the recombinant protein was 100kDa, which decreased to 85 kDa after treatment with endoglycosidase H. The recombinant GhCesA2 catalyzed transfer of glucose from UDP-glucose into unknown products in the presence of an extract of cotton hypocotyls, but the products were not-1,4-glucan.     

On the radial-growth variations of Japanese beech <Emphasis Type="Italic">(Fagus crenata)</Emphasis> on the northernmost part of Honshu Island,Japan

We developed ring-width chronologies for living trees of Japanese beech at two forest sites on the northern-most part of Honshu Island, Japan. A statistical threshold (running expressed population signal) yielded these site chronologies spanning 1853–1994 (142 years) and 1867–1994 (128 years). We examined two factors, climate and masting, that could affect the variations of radial growth. The response function analysis revealed that the ring width correlated positively with July and August temperatures of the previous growth year. The optimal radial growth of Japanese beech may largely depend on a warm previous summer with above-average temperatures. The years of good masting coincided mostly with those showing abrupt growth depression, although only the short-term records of masting were available. Part of this work was presented at the 6th Pacific Regional Wood Anatomy Conference, Kyoto, December 2005, and the 7th International Conference on Dendrochronology, Beijing, June 2006     

Studies on Endophytic Actinomycetes ( I ) <Emphasis Type="Italic">Streptomyces </Emphasis>sp. Isolated from Rhododendron and Its Antifungal Activity

To survey endophytic actinomycetes as potential biocontrol agents against fungal diseases of rhododendron, young plants of rhododendron were surface-sterilized for use as an isolation source. Nine, six and two isolates, with distinguishing characteristics based on the macroscopic appearance of colonies, were obtained from roots, stems and leaves, respectively, suggesting that various species of actinomycetes grow in the respective organs of this plant as symbionts or parasites. On an agar medium, only isolate R-5 commonly formed a clear growth-inhibition zone against two major fungal pathogens of rhododendron, Phytophthora cinnamomi and Pestalotiopsis sydowiana, indicating that this isolate can produce antifungal material(s). Acetone extracts of a liquid culture of R-5 had a broad antimicrobial spectrum against Gram-positive bacteria, yeast and filamentous fungi. Isolate R-5 was identified as a Streptomyces sp. based on morphological, physiological and chemotaxonomical characteristics. The present results indicate that isolate R-5 is a suitable candidate for the biocontrol of diseases of rhododendron. Received 25 March 2000/ Accepted in revised form 18 May 2000     

Biological features of canine cancer-associated fibroblasts and their influence on cancer cell invasion

Cancer-associated fibroblasts (CAFs) play an essential role in tumor invasion and metastasis. In dogs, the biological features of CAFs have not been well characterized. The purpose of this study was to investigate differences in the biological activities of canine CAFs and normal fibroblasts (NFs), and their influence on the migration and invasion of cancer cells. Canine CAFs and NFs were harvested from surgically-resected malignant epithelial tumor tissues and skin tissues of dogs. A wound-healing assay was conducted to compare the migratory and invasive abilities of canine CAFs and NFs. The results of this study showed that canine CAFs have a greater migratory and invasive ability than NFs. To observe the indirect and direct interactions between fibroblasts and cancer cells, Boyden chamber assay and 3D co-culture with collagen gel were conducted. The number of migrated and infiltrated cancer cells co-cultured with canine CAFs was greater than that with NFs. In the 3D co-culture, cancer cells showed noteworthy proliferation on the surface of gels containing canine CAFs and invasion into the gel. On the other hand, no infiltration of cancer cells into the gel containing NFs was observed. It was suggested that canine CAFs activate migration and invasion of cancer cells and promote the infiltration of cancer cells into collagen gels.