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111.
Mitsutoshi Kato Jie Yang Takaaki Iwai Akira Tanamura Toru Arino Osamu Kawashima Nobuakira Takeda 《Molecular and cellular biochemistry》1993,119(1-2):89-94
ADP/ATP carrier protein (AAC) is located in the mitochondrial inner membrane and has an important function in mitochondrial energy supply. This protein transports ATP to the cytoplasm and counter transports ADP into the mitochondria. J-2-N cardiomyopathic hamsters were investigated to determine the AAC content in cardiac mitochondria. After recording an electrocardiogram and collecting blood, the cardiac mitochondria were isolated. The mitochondrial membranes were labelled with eosin-5-maleimide (EMA) and separated on SDS polyacrylamide gels. The position of the AAC component was identified by exposing the gel under UV light, and the AAC content was determined by densitometry after staining with Coomassie blue. The AAC content ratio was significantly decreased in both 10-week-old and 1-year survived J-2-N hamsters when compared to control Golden hamster. Among 10-week-old J-2-N hamsters, the decrease in the AAC content ratio was more marked for the animals with more severe myocardial damage. The H+-ATPase activities of mitochondrial membrane were higher in 10-week-old J-2-N hamsters than in control hamsters. These results suggest that the decrease of AAC in J-2-N hamster plays an important role in the pathogenesis of cardiomyopathy in J-2-N hamsters. 相似文献
112.
Tobacco plants were transformed with derivatives of a binary vector pMON505 and two kanamycin resistant lines that were nopaline positive were selected for second transformation. The plasmids used for the second transformation were derivatives of pMON850 which carries the nopaline synthase gene in addition to a gene for gentamicin resistance. Insertion of each transgene was confirmed by Southern hybridization. Surprisingly, we found that more than 50% of the doubly transformed tobacco plants were nopaline negative. Tobacco plants that were transformed only by the second vector exhibited nopaline accumulation. DNA methylation patterns at the HpaII site in the promoter region of the nopaline synthase gene did not correlate with the nopaline phenotype. In some plant lines, seedlings of the R1 generation which segregated out the second T-DNA insertion recovered the nop+ phenotype. These results indicate that nopaline accumulation was inhibited by the presence of the second T-DNA.Abbreviations T-DNA
transferred DNA
- NPTII
neomycin phosphotransferase II
-
uidA
-glucuronidase
- Km
kanamycin
- Gm
gentamicin
- nop+
nopaline positive
- nop–
nopaline negative
- MS
medium, Murashige-Skoog medium 相似文献
113.
Toru Terachi 《Journal of plant research》1993,106(1):75-79
Recent advances in manipulating nucleic acids have opened a new research field called plant molecular systematics. This short
review provides an overview of molecular techniques which have been used in the analysis of DNA molecules for the study of
plant systematics, with a special emphasis on PCR. The early application of DNA analysis, DNA/DNA hybridization, has not become
popular with plant systematists, because of several disadvantages inherent in the method. The survey of restriction fragment
length polymorphisms (RFLPs), on the contrary, has become one of the preferred methods used by plant molecular systematists,
since the method is relatively easy to perform. Although unambiguous data can be obtained by both long-range restriction mapping
and nucleotide sequencing, these approaches may have limited use in plant molecular systematics because of their laborious
experimental procedures relying on conventional molecular cloning techniques. To date, PCR based analyses of the DNA molecule
seem to be the most suitable experimental approach for plant molecular systematics. Several advantages of the method have
changed both the quality and quantity of the DNA data. Further application of PCR to plant molecular systematics will open
up a new era in the field.
The present paper is based on the contribution which was read in a symposium entitled “Organellar DNA Variations in Higher
Plants and their Taxonomic Significance”, at the 50th Annual Meeting of the Botanical Society of Japan in Shizuoka on October
2, 1990, under the auspices of the Japan Society of Plant Taxonomists. 相似文献
114.
Kanji Hori Yoshiharu Shimada Chihiro Oiwa Keisuke Miyazawa Keiji Ito 《Journal of applied phycology》1993,5(2):219-223
Nine species of marine algae have been assessed for the presence of novel hemagglutinins not extractable with buffer, unless
the algal tissue was pretreated with Pronase. All species examined contained hemagglutinins, indicating the existence of a
novel group of hemagglutinins which differed from those reported previously in marine algae. 相似文献
115.
116.
An Improved Enrichment Broth for Isolation of Escherichia coli O157, with Specific Reference to Starved Cells, from Radish Sprouts 下载免费PDF全文
Shin Sata Tomohiko Fujisawa Ro Osawa Atsushi Iguchi Shiro Yamai Toshio Shimada 《Applied microbiology》2003,69(3):1858-1860
An enrichment broth was developed for the efficient isolation of Escherichia coli O157 from radish sprouts. The broth was buffered peptone water containing 0.5% sodium thioglycolate (STG-BPW), which was designed to allow growth of E. coli O157 in starved and unstarved states. However, this medium suppressed the growth of non-carbohydrate-fermenting obligate aerobes whose colonial appearance on sorbitol MacConkey agar containing cefixime and tellurite (CT-SMAC) resembled that of E. coli O157. Both starved and unstarved cells of E. coli O157 experimentally inoculated into radish sprouts were successfully recovered with STG-BPW enrichment in all cases, most of which showed marked disappearance of E. coli O157-like colonies on CT-SMAC. 相似文献
117.
118.
119.
A. Abo-elwafa K. Murai T. Shimada 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(3-4):335-340
Randomly amplified polymorphic DNA (RAPD) markers were used to estimate intra- and interspecific variations in the genus Lens (lentil). Twenty cultivars of L. culinaris ssp. culinaris, including 11 microsperma (small-seeded) and nine macrosperma (large-seeded) types, and 16 wild relatives (four accessions each of L. culinaris ssp. orientalis, L. odemensis, L. nigricans and L. ervoides), were evaluated for genetic variability using a set of 40 random 10-mer primers. Fifty reproducibly scorable DNA bands were observed from ten of the primers, 90% of which were polymorphic. Genetic distances between each of the accessions were calculated from simple matching coefficients. A dendrogram showing genetic relationships between them was constructed by an unweighted pair-group method with arithmetical averages (UPGMA). This study revealed that (1) expect for L. ervoides, the level of intraspecific variation in cultivated lentil is lower than that in wild species, (2) L. culinaris ssp. orientalis is the most likely candidate for a progenitor of the cultivated species, and (3) microsperma and macrosperma cultivars were indistinguishable by the RAPD markers identified here. 相似文献
120.
Kadokawa H Minezawa M Yamamoto Y Takahashi M Shimada K Takahashi H Kariya T 《Theriogenology》1995,44(2):295-306
Heterosexual chimerism among singleton females produced by multiple nonsexed embryo transfer (MNET singleton females) was investigated using chromosome typing and PCR (polymerase chain reaction)-amplification of male-specific DNA (msDNA). Of the 22 animals tested, 21 were classified as normal by both methods (i.e., showing no male cells among 100 metaphase spreads in chromosome typing and being msDNA negative in PCR). No morphological abnormalities of the genital organs were observed among 19 MNET single females. One MNET singleton female was, however, classified as a freemartin by PCR (male-specific DNA positive), but it was classified as normal cytogenetically. This individual probably had a low degree of heterosexual chimerism, and it seems that the chimerism derived from MNET was difficult to diagnose by chromosome typing, although it was detectable by PCR. The genital organs of this individual (15-mo-old Aberdeen Angus) were normal in form (both external and internal) and size. However, a very small structure, resembling seminiferous tubule, was found in the left ovary. It may be concluded that most MNET singleton females are expected to have normal reproductive function. 相似文献