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371.
Satoshi ITO Haruhiko INOUE Takanori KOBAYASHI Masaaki YOSHIBA Satoshi MORI Naoko K. NISHIZAWA Kyoko HIGUCHI 《Soil Science and Plant Nutrition》2009,55(2):277-282
Barley ( Hordeum vulgare L.) nicotianamine synthase gene ( HvNAS1 ) expression in barley is strongly induced by Fe deficiency in the roots and rice ( Oryza sativa L.) nicotianamine synthase gene ( OsNAS1 ) expression in rice is induced by Fe deficiency both in the roots and in the shoots. In dicots, NAS genes are not strongly induced by Fe deficiency, and they function to maintain Fe homeostasis. Rice OsNAS1promoter::GUS or barley HvNAS1promoter::GUS was introduced into tobacco ( Nicotiana tabacum L.) and tissue specificities and systemic regulation of their expression were compared. A split-root experiment revealed that the HvNAS1 promoter exhibited functions similar to those of Fe-acquisition-related genes in tobacco roots, suggesting that this promoter responded to certain Fe-deficiency systemic signals and to the Fe concentration in the rhizosphere. The HvNAS1 promoter might harbor a type of universal system of gene expression for Fe acquisition. However, the OsNAS1 promoter did not respond to local application of Fe to the roots and induced GUS activities in mature leaves in response to Fe deficiency. This promoter might possess numerous types of cis -acting sequences that are involved in Fe metabolism. 相似文献
372.
Takanori Ohsako Takafumi Ohgushi Hino Motosugi Kouzou Oka 《Genetic Resources and Crop Evolution》2008,55(7):1047-1053
Genetic variability within and among eight landrace populations of tea (Camellia sinensis (L.) O. Kuntze) located in southern Kyoto, Japan, was surveyed with six microsatellite markers. The average number of alleles
per locus was 3.83 to 4.67 for landrace populations, whereas the corresponding value among modern cultivars and breeding lines
was 6.63. Expected heterozygosity values averaged over loci within landrace populations ranged from 0.498 to 0.723. A similar
level of variation, 0.682, was observed for cultivars and breeding lines. High fixation index values (0.177–0.417) for each
population are consistent with biparental inbreeding within the population. Genetic differentiation among local populations
was extremely low with F
ST = 0.062, although AMOVA revealed significant differentiation among landrace populations. We propose that these populations
share a common ancestral gene pool and that some degree of artificial selection within each population has been performed
by local farmers. Neighbor-joining analysis revealed that genetic relationships among populations reflect geographical location
of populations. This might result from more frequent genetic exchange by nearby farmers. 相似文献
373.
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375.
Akifumi Mizuno Takanori Tsukamoto Yoshiaki Shimizu Hitoshi Ooya Takayuki Matsuura Norihiko Saito Shigeyoshi Sato Shigemi Kikuchi Tsuneyasu Uzuki Kouji Azegami 《Journal of General Plant Pathology》2010,76(1):43-51
Black lesions on shoots of European pear trees observed in an orchard in Yamagata Prefecture in May 2007 were suspected to
be caused by a bacterial pathogen. The surface of the colonies isolated on a high sucrose medium did not have the crater morphology
that is characteristic of E. amylovora bvs. 1–3, and a specific DNA fragment was amplified from the isolates in the PCR using the EprpoD primer set. The partial
sequences of the 16S rRNA gene placed the isolates in the genus Erwinia. The isolates differed serologically from E. amylovora biovars and E. pyrifoliae in an Ouchterlony double-diffusion test although their bacterial properties suggested that they are closely related to E. amylovora biovars and E. pyrifoliae. In a DNA–DNA hybridization test, the relatedness between the isolates and E. amylovora biovars or E. pyrifoliae did not exceed 70% level, indicating that they are independent species. Thus, the isolates belongs to the genus Erwnia but are not E. amylovra or E. pyrifoliae. After succulent pear shoots were injected with bacterial suspensions (109, 108, 107 and 106 cfu/ml) of the isolates, lesions formed with 109 and 108 cfu/ml, but the disease incidence with 108 cfu/ml was much lower than with E. amylovora and E. pyrifoliae. Virulence of the present isolates is thus thought to be very weak. On the basis of these results, we consider that this
is a new shoot disease of European pear. In the 2007 season, all affected trees were pulled out after harvest. No symptoms
have been observed in field surveys since the fruitlet season in 2007. 相似文献
376.
Naomi TERAMOTO Masanari IKEDA Hidetoshi SUGIHARA Takanori SHIGA Takashi MATSUWAKI Masugi NISHIHARA Kazuyuki UCHIDA Keitaro YAMANOUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(9):1416
Rhabdomyosarcoma (RMS) is an aggressive type of soft tissue sarcoma, and pleomorphic RMS is a rare subtype of RMS found in adult. p16 is a tumor suppressor which inhibits cell cycle. In human RMS, p16 gene is frequently deleted, but p16-null mice do not develop RMS. We reported that genetic ablation of p16 by the crossbreeding of p16 knock-out rats (p16-KO rats) improved the dystrophic phenotype of a rat model of Duchenne muscular dystrophy (Dmd-KO rats). However, p16/Dmd double knock-out rats (dKO rats) unexpectedly developed sarcoma. In the present study, we raised p16-KO, Dmd-KO, and dKO rats until 11 months of age. Twelve out of 22 dKO rats developed pleomorphic RMS after 9 months of age, while none of p16-KO rats and Dmd-KO rats developed tumor. The neoplasms were connected to skeletal muscle tissue with indistinct borders and characterized by diffuse proliferation of pleomorphic cells which had eosinophilic cytoplasm and atypical nuclei with anisokaryosis. For almost all cases, the tumor cells immunohistochemically expressed myogenic markers including desmin, MyoD, and myogenin. The single cell cloning from tumor primary cells gained 20 individual Pax7-negative MyoD-positive RMS cell clones. Our results demonstrated that double knock-out of p16 and dystrophin in rats leads to the development of pleomorphic RMS, providing an animal model that may be useful to study the developmental mechanism of pleomorphic RMS. 相似文献