The use of micro-beam X-ray diffraction for the characterization of starch crystal structure in rice mutant kernels of waxy, amylose extender, and sugary1     

Akiko Kubo  Yoshiaki Yuguchi  Makoto Takemasa  Shiho Suzuki  Hikaru Satoh  Shinichi Kitamura   《Journal of Cereal Science》2008,48(1):92-97

Micro-beam X-ray diffraction analyses were carried out on slices from wild-type rice and mutants. The method permitted the crystalline structure to be analyzed with less destruction of cells and fewer artificial effects that occur during the purification of starch from tissue and provided information concerning the localization and crystalline structure of starches distributed in the endosperm. The starch on kernel slices from the wild-type and waxy mutant, carrying a defect for the Granule-bound starch synthase I (GBSSI) gene, displayed an A-type of diffraction pattern; no difference in the crystalline patterns between starches located in the inner and outer region in a kernel were observed. A double mutant of the waxy and amylose extender (ae) mutant carrying a defect for the Starch branching enzyme IIb gene accumulated amylose-free B-type starches. The kernel slice from the double mutant of waxy and sugary1, mutated on the Isoamylase I locus, displayed an A-type diffraction pattern in the outer region and was amorphous in the inner region. A chain-length distribution analysis of polyglucans in kernels from wild-type and mutants showed that ae amylopectin had more long chains and less short chains than the wild-type and waxy amylopectin. On the other hand, the water-soluble polysaccharide in the inner region of the sugary1 endosperm had more short chains than the amylopectin in the outer region counterparts. These results indicate that branch chain length in amylopectin is crucial in determining the formation of A- and B-type starches.  相似文献   

Caulogenic callus induction and adventitious bud formation from embryos of long-term stored seeds ofPicea jezoensis     

Shinjiro Ogita  Takafumi Kubo  Masami Fushitani 《Journal of Forest Research》1997,2(3):141-145

Caulogenic calli with a high differentiation potency were induced from mature embryos ofPicea jezoensis seeds stored over a long time, for 29 years, resulting in the active formation of adventitious buds. Embryos began to induce calli within 3 weeks of cultivating on LP medium containing 3 μM BAP and 1 μM 2,4-D. Then, the calli proliferated and transformed into caulogenic calli with bud primordia in 8 weeks. The caulogenic calli increased actively with the addition of 500 mg/l ofl-glutamine in the medium. Furthermore, caulogenic calli, induced on LP medium containingl-glutamine, resulted in the formation of adventitious buds, which elongated after transferring the calli into LP medium with 0.1 μM BAP, but withoutl-glutamine. It appears that the number of adventitious buds and the process of shoot elongation are influenced by the kind of nitrogen contained in the medium for callus induction. A part of this study was presented at the 107th Annual Meeting of the Japanese Forestry Society (1996).  相似文献   

Influence of osmotic pressure on somatic embryo maturation in Pinus densiflora     

Mariko Shoji  Hidenori Sato  Remi Nakagawa  Ryo Funada  Takafumi Kubo  Shinjiro Ogita 《Journal of Forest Research》2006,11(6):449-453

The effect of an osmoticum, polyethylene glycol (PEG), on somatic embryo production was examined using embryogenic cells of Pinus densiflora. In the basal medium containing 30 μM abscisic acid and 6% maltose, the quality of the embryos formed was poor even though somatic embryos were produced. The addition of PEG with molecular weight of 4000 or 8000 significantly enhanced the development of both the quality and quantity of somatic embryos. Furthermore, higher levels of a constant osmotic pressure with PEG 8000 in a range from about 300 to 450 mmol/kg could remarkably enhance the morphogenesis of somatic embryos and their number of embryos produced. A higher stable osmotic pressure with an appropriate molecular weight of PEG is a key factor for the production of good quality somatic embryos in P. densiflora.  相似文献   

Effect of heat on cambial reactivation during winter dormancy in evergreen and deciduous conifers     

Oribe Y  Kubo T 《Tree physiology》1997,17(2):81-87

Responses of cambium to warming were recorded three times (December 14-27, 1990, January 18-February 3 and February 27-March 13, 1991) on 14-year-old Cryptomeria japonica D. Don and four times (December 12-26, 1990, January 18-February 2, February 26-March 12 and March 28-April 13, 1991) on 27-year-old Larix leptolepis Gord., during a period of winter cambial dormancy. Stem surfaces at breast height, mid-tree height and the crown base were warmed to 25-30 degrees C for 2 weeks. After heat treatment, cambia in the treated regions and in untreated regions 1 m above each treated area were examined by optical and transmission electron microscopy (TEM). In C. japonica, heat treatment often resulted in cambial reactivation in the treated regions, and this response to heat gradually increased as the dormant season passed from winter to spring. Conversely, in L. leptolepis, no cell division was observed in the cambial region of warmed stems until natural resumption of cambial activity, which occurred after bud break.  相似文献   

Mapping of a gene that confers short lateral branching (slb) in melon (Cucumis melo L.)     

N. Fukino  T. Ohara  M. Sugiyama  N. Kubo  M. Hirai  Y. Sakata  S. Matsumoto 《Euphytica》2012,187(1):133-143

Plant architecture plays an important role in the yield, product quality, and cultivation practices of many crops. Branching pattern is one of the most important components in the plant architecture of melon (Cucumis melo L.). ‘Melon Chukanbohon Nou 4 Go’ (Nou-4) has a short-lateral-branching trait derived from a weedy melon, LB-1. This trait is reported to be controlled by a single recessive or incompletely dominant major gene called short lateral branching (slb). To find molecular markers for marker-assisted selection of this gene, we first constructed a linkage map using 94 F₂ plants derived from a cross between Nou-4 and ‘Earl’s Favourite (Harukei-3)’, a cultivar with normal branching. We then conducted quantitative trait locus (QTL) analysis and identified two loci for short lateral branching. A major QTL in linkage group (LG) XI, at which the Nou-4 allele is associated with short lateral branching, explained 50.9 % of the phenotypic variance, with a LOD score of 12.5. We suggest that this QTL corresponds to slb because of the magnitude of its effect. Another minor QTL in LG III, at which the Harukei-3 allele is associated with short lateral branching, explained 9.9 % of the phenotypic variance, with a LOD score of 4.2. Using an independent population, we demonstrated that an SSR marker linked to the QTL in LG XI (slb) could be used to select for short lateral branching. This is the first report of mapping a gene regulating the plant architecture of melon.  相似文献   

An SSR-based genetic map of pepper (Capsicum annuum L.) serves as an anchor for the alignment of major pepper maps     

Yutaka Mimura  Takahiro Inoue  Yasuhiro Minamiyama  Nakao Kubo 《Breeding Science》2012,62(1):93-98

Of the Capsicum peppers (Capsicum spp.), cultivated C. annuum is the most commercially important, but has lacked an intraspecific linkage map based on sequence-specific PCR markers in accord with haploid chromosome numbers. We constructed a linkage map of pepper using a doubled haploid (DH) population derived from a cross between two C. annuum genotypes, a bell-type cultivar ‘California Wonder’ and a Malaysian small-fruited cultivar ‘LS2341 ({"type":"entrez-nucleotide","attrs":{"text":"JP187992","term_id":"347495878"}}JP187992)’, which is used as a source of resistance to bacterial wilt (Ralstonia solanacearum). A set of 253 markers (151 SSRs, 90 AFLPs, 10 CAPSs and 2 sequence-tagged sites) was on the map which we constructed, spanning 1,336 cM. This is the first SSR-based map to consist of 12 linkage groups, corresponding to the haploid chromosome number in an intraspecific cross of C. annuum. As this map has a lot of PCR-based anchor markers, it is easy to compare it to other pepper genetic maps. Therefore, this map and the newly developed markers will be useful for cultivated C. annuum breeding.  相似文献   

Histopathological and immunohistochemical evaluation of the first case of BSE in Japan     

Kimura KM  Haritani M  Kubo M  Hayasaka S  Ikeda A 《The Veterinary record》2002,151(11):328-330

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Studies on mechanisms of appressorial penetration by Colletotrichum lagenarium     

Yasuyuki Kubo 《Journal of General Plant Pathology》2005,71(6):451-453

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Identification of genes expressed during spore germination of Mycosphaerella pinodes     

Hiroyuki Takahara  Kazuhiro Toyoda  Gento Tsuji  Yasuyuki Kubo  Yoshishige Inagaki  Yuki Ichinose  Tomonori Shiraishi 《Journal of General Plant Pathology》2005,71(3):190-195

Mycosphaerella blight, caused by Mycosphaerella pinodes, is one of the major diseases of cultivated pea (Pisum sativum L.). To isolate the genes that are up- and down-regulated during spore germination, suppression subtraction hybridization (SSH) was performed between ungerminated and germinated spores. The 232 and 128 clones from forward and reverse libraries, respectively, were collected, sequenced, and analyzed with a BLASTX homology search. About 95% of the 32 selected clones were expressed during spore germination on a paper sheet and during infection of pea leaves. We discuss the applicability of the SSH libraries for analyzing M. pinodes genes involved in the early stage of infection.  相似文献   

Retrospective serological analysis of spontaneous CDV infection in 192 dogs   总被引：1，自引：0，他引：1  

Kubo T  Kagawa Y  Taniyama H  Hasegawa A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(5):475-477

Spontaneous cases of canine distemper virus (CDV) infection were serologically evaluated. The 192 dogs in which CDV antigen was confirmed from tonsil by immunohistological examination were 2- to 4-months old, of various breeds, and unvaccinated. The prognoses were good in 74 dogs with significantly high levels of anti-CDV passive hemolytic aggregation (PHA) titer. In the other 118 dogs with poor prognoses, anti-CDV PHA titer was not detected. Anti-CDV PHA titer had the most significant association with the prognoses of CDV infection, and could be the most reliable and useful indicator for evaluating such prognoses.  相似文献