Molecular characterization of A2 and D strains of Soybean mosaic virus, which caused a recent virus outbreak in soybean cultivar Sachiyutaka in Chugoku and Shikoku regions of Japan

Coat protein sequences of two isolates in strain A₂ and five isolates in strain D of Soybean mosaic virus (SMV), which caused a recent mosaic outbreak in soybeans (cv. Sachiyutaka) in Chugoku and Shikoku in Japan, were compared to published data on 15 other Asian-origin isolates. Sequence comparison and cluster analysis showed that SMV isolates of strain A₂ from these districts were closely related, as were those of strain D, but strains A₂ and D were not. Thus, the two strains may have different origins and be carried through seed transmission.     

Cytogenetic analysis and developmental assessment of mouse embryos derived from in vitro fertilization of oocytes reconstructed by meiosis-II chromosome transplantation

An electrofusion methodology for transferring meiosis-II chromosomes (M-II-t) has not been completely established. The present study compared the use of two temperatures (fusion at 37 C for Group A and 25 C for Group B) during an electrofusion procedure for mouse oocyte M-II-t and investigated the cytogenetic normality and developmental competence of embryos derived from in vitro fertilization using oocytes reconstructed by M-II-t. The M-II-t oocytes were fertilized in vitro and cultured to the blastocyst stage; the resultant embryos were analyzed cytogenetically. Subsequently, chromosomal normality of the resultant embryos at the prometaphase stage of first cleavage division and the integrity of the meiosis-II spindles of the reconstructed oocytes were analyzed. The success rate of electrofusion in Group B was 92.1%, which was significantly different from that in Group A (49.2%) (P<0.05). The fertilization rates (A, 80.7%; B, 77.2%) and development rates (A, 70.9%; B, 65.5%) in the M-II-t groups were significantly lower than those in the control group (95.0 and 92.2%, respectively) (P<0.05). The incidence of chromosomal abnormalities in the Group A embryos (20.5%) at the blastocyst stage was significantly higher than that in the control group embryos (8.5%) (P<0.05), but the incidence of chromosomal abnormalities in Group B (12.5%) was not significantly different compared with the other groups. A temperature of 25 C during the electrofusion procedure for M-II-t resulted in a good fusion rate, good development rate, and efficient production of chromosomally normal blastocysts. Furthermore, the incidence of chromosomal abnormalities in the first cleavage embryos at the prometaphase stage in Group B (9.6%) did not differ significantly from that in the control group (6.6%). The spindle morphology of the M-II-t oocytes in Group B was normal.     

Effects on flowering and seed yield of dominant alleles at maturity loci E2 and E3 in a Japanese cultivar,Enrei

‘Enrei’ is the second leading variety of soybean (Glycine max (L.) Merr.) in Japan. Its cultivation area is mainly restricted to the Hokuriku region. In order to expand the adaptability of ‘Enrei’, we developed two near-isogenic lines (NILs) of ‘Enrei’ for the dominant alleles controlling late flowering at the maturity loci, E2 and E3, by backcrossing with marker-assisted selection. The resultant NILs and the original variety were evaluated for flowering, maturity, seed productivity and other agronomic traits in five different locations. Expectedly, NILs with E2 or E3 alleles flowered later than the original variety in most locations. These NILs produced comparatively larger plants in all locations. Seed yields were improved by E2 and E3 in the southern location or in late-sowing conditions, whereas the NIL for E2 exhibited almost the same or lower productivity in the northern locations due to higher degrees of lodging. Seed quality-related traits, such as 100-seed weight and protein content, were not significantly different between the original variety and its NILs. These results suggest that the modification of genotypes at maturity loci provides new varieties that are adaptive to environments of different latitudes while retaining almost the same seed quality as that of the original.     

Prevention of progeny formation in Drosophila melanogaster by 1-arylimidazole-2(3H)-thiones

Effects of 1-arylimidazole-2(3H)-thiones (AITs) and 1-(substituted benzyl)imidazole-2(3H)-thiones (BITs) were tested on progeny formation in Drosophila melanogaster. Some AITs showed inhibitory activities at laying eggs and delayed eclosion by 1 day. The inhibitory activity was nullified by adding octopamine (OA) or noradrenaline (NA) to the medium for progeny formation in D. melanogaster. The effect of AIT on the contents of OA and NA was analyzed in adults of D. melanogaster by high-performance liquid chromatography with electrochemical detection. Flies fed with AIT decreased OA and NA levels and increased TA content. Taken together, the inhibitory activity of AIT could be due to inhibition of tyramine β-hydroxylase and dopamine β-hydroxylase.     

Catalog of Micro-Tom tomato responses to common fungal, bacterial, and viral pathogens

Lycopersicon esculentum cultivar Micro-Tom is a miniature tomato with many advantages for studies of the molecular biology and physiology of plants. To evaluate the suitability of Micro-Tom as a host plant for the study of pathogenesis, Micro-Tom plants were inoculated with 16 well-known fungal, bacterial, and viral pathogens of tomato. Athelia rolfsii, Botryotinia fuckeliana, Oidium sp., Phytophthora infestans, and Sclerotinia sclerotiorum caused typical symptoms and sporulated abundantly on Micro-Tom. Micro-Tom was resistant to Alternaria alternata, Corynespora cassiicola, and Fusarium oxysporum. When Micro-Tom was inoculated with 17 isolates of Ralstonia solanacearum, many isolates induced wilt symptoms. Agrobacterium tumefaciens also was pathogenic, causing crown galls on stem tissue after needle prick inoculation. In Micro-Tom sprayed with Pseudomonas syringae pv. tomato, P. s. pv. tabaci, or P. s. pv. glycinea, bacterial populations did not increase, and yellow lesions appeared only on leaves sprayed with P. s. pv. tomato. Tomato mosaic virus, Tomato aspermy virus, and Cucumber mosaic virus systemically infected Micro-Tom, which developed symptoms characteristic of other cultivars of tomato after infection with the respective virus. These results indicated that Micro-Tom was generally susceptible to most of the important tomato pathogens and developed typical symptoms, whereas certain pathogens were restricted by either hypersensitive resistance or nonhost resistance on Micro-Tom. Therefore, an assortment of Micro-Tom–pathogen systems should provide excellent models for studying the mechanism of susceptible and resistant interactions between plants and pathogens.     

Exophthalmos Caused by Chronic Sinusitis in a Horse: A Case of Exophthalmos Caused by Sinusitis

A 12-year-old Thoroughbred gelding exhibited a unilateral exophthalmos on the left side. There had been no other clinical symptoms, such as rhinorrhea, before the first consultation. Clinical, hematologic, plasma biochemical, cytologic, and computed tomography (CT) examinations and complete necropsy were performed. These examinations did not reveal neoplastic lesions. CT images suggested that maxillary and frontal sinuses may have been filled with fluid. Cytologic and pathologic examinations revealed that the maxillary and orbital bones were pushed up with a large amount of the inflammatory fluid effused by chronic sinusitis. The CT and cytologic examinations were of great use for differential diagnosis in this case. This was an unusual case of exophthalmos induced by deformation of the orbital bones resulting from chronic sinusitis.     

Triterpenoids isolated from Zizyphus jujuba inhibit foam cell formation in macrophages

Because foam cell formation in macrophages is believed to play an essential role in the progression of early atherosclerotic lesions in vivo, prevention of foam cell formation is considered to be one of the major targets for the treatment of atherosclerosis. The present study examined the inhibitory effect of 50 crude plant extracts on foam cell formation. Among those crude extracts, Zizyphi Fructus (ZF) and Zizyphi Semen (ZS) extracts significantly inhibited the foam cell formation induced by acetylated LDL. Furthermore, triterpenoids such as oleanonic acid, pomolic acid, and pomonic acid were the major active compounds, and triterpenoids containing a carboxylic acid at C-28 play an important role in the inhibitory effect on foam cell formation in human macrophages. These data suggest that triterpenoids in Zizyphus jujuba , the plant source of ZF and ZS, may therefore be useful for the prevention of atherosclerosis.