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N. Fujii N. Tomaru K. Okuyama T. Koike T. Mikami K. Ueda 《Plant Systematics and Evolution》2002,232(1-2):21-33
CpDNA variation in Japanese beech, Fagus crenata (Fagaceae), was studied in 45 populations distributed throughout the species' range. Two cpDNA regions were sequenced: the
non-coding region between the trnL (UAA) 5′exon and trnF (GAA), and the trnK region (including matK). Thirteen distinct cpDNA haplotypes were recognized and each haplotype was found to be geographically structured. Two major
clades (I and II+III) were revealed in phylogenetic analyses among the haplotypes using F. sylvatica as an outgroup. The haplotypes of Clade I were distributed mainly along the Japan Sea side of the Japanese Archipelago, while
those of Clade II+III occurred chiefly along the Pacific Ocean side. Consequently, the distribution of the two major cpDNA
clades suggests that there were two migration routes in the history of F. crenata; one along the Japan Sea and the other along the Pacific Ocean side of the Japanese Islands.
Received March 19, 2001 Accepted November 22, 2001 相似文献
7.
V L Young C A Gumucio H Lund R McMahon K Ueda L Pidgeon 《Plastic and reconstructive surgery》1992,89(1):70-6; discussion 77-8
Using the monkey model previously developed, we investigated the long-term effects of retrobulbar hematoma-induced retinal ischemia on functional vision and retinal histology. In this experimental model, ischemic periods of up to 120 minutes did not cause permanent visual deficits, as measured by flashed evoked visual potentials. Similarly, retinal histology showed no evidence of ischemic injury. From this we conclude that blindness after blepharoplasty is not due to retrobulbar hematomas alone and that additional predisposing factors are involved. The most likely additional factor is preexisting occult vascular ocular pathology. 相似文献
8.
Summary ThePhysarum plasmodium shows rhythmic contractile activities with a period of a few min. Phases of the oscillation in the plasmodium migrating unindirectionally agreed sideways throughout at the frontal part. So, time course of an intracellular chemical component was determined by analyzing small pieces cut off successively from the frontal part of the large plasmodium. Intracellular NAD(P)H concentration oscillated with the same period as the rhythmic contraction but with a different phase advancing about 1/3 of the period. UV irradiation suppressed the rhythmic contraction without affecting the rhythmic variation of NAD(P)H. Thus, the NAD(P)H oscillator works independently of the rhythmic contractile system, but seems entraining with each other.Abbreviations UV
ultraviolet
- NADH
nicotinamide adenine dinucleotide, reduced form
- NADPH
nicotinamide adenine dinucleotide phosphate, reduced form
- ATP
adenosine 5-triphosphate
- cAMP
cyclic adenosine 3, 5-monophosphate
- FMNH2
flavin mononucleotide, reduced form
- TCA
tricarboxylic acid
- BSA
bovine serum albumin
- DTT
dithiothreitol 相似文献
9.
Isolation of several cDNAs encoding yeast peroxisomal enzymes 总被引:1,自引:0,他引:1
Several candidate clones carrying partial cDNAs for yeast peroxisomal enzymes, such as catalase, carnitine acetyltransferase, isocitrate lyase, malate synthase and acyl-CoA oxidase, were efficiently isolated at a single plating from a phage lambda gt11 recombinant cDNA library prepared with poly(A)-rich RNA from an n-alkane-grown yeast, Candida tropicalis, with a mixture of antibodies against the respective purified enzymes. Among them, one candidate clone carrying partial cDNA for catalase was subcloned and subjected to nucleotide sequence analysis. We succeeded in determining that the amino acid sequence deduced from the nucleotide analysis included the sequences derived from the two peptide fragments obtained from the purified enzyme. 相似文献
10.
H Ueda Y Yoshihara N Fukushima H Shiomi A Nakamura H Takagi 《The Journal of biological chemistry》1987,262(17):8165-8173
Kyotorphin (Tyr-Arg) is a unique neuropeptide which produces analgesia by releasing Met-enkephalin from slices of the brain and spinal cord. Recent studies revealed that kyotorphin possesses the properties of neurotransmitter/neuroregulator. In the present study, we identified a kyotorphin synthetase in the soluble fraction of rat brain synaptosomes (synaptosol) and characterized it. The enzyme partially purified with Sephacryl S-300 showed an absolute requirement for ATP, MgCl2, tyrosine, and arginine. The optimal pH was 7.5-9.0 and the pI was determined to be 6.1-6.2 by isoelectric focusing. The Km was 25.6 microM for tyrosine, 926 microM for arginine, 294 microM for ATP, and 442 microM for MgCl2. The Vmax was 34.0 pmol/mg of protein/h. The apparent molecular size of this "kyotorphin synthetase" further purified by the DE52 column was 240,000-245,000 daltons, estimated using TSKgel G4000SW column chromatography. The enzyme reaction is represented by the following equation: Tyr + Arg + ATP + MgCl2 + kyotorphin synthetase----Tyr-Arg (kyotorphin) + AMP + PPi + MgCl2 + kyotorphin synthetase. The regional distribution and subcellular localization of the synthetase showed a close correlation to that of kyotorphin levels in the rat brain. The amounts of kyotorphin formed from amino acids by the synthetase in the dialyzed synaptosol was 3.0-4.0 times higher than that from precursor proteins by processing enzymes within the 30 min incubation. 相似文献