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41.
Location and characterization of autonomously replicating sequences from chromosome VI of Saccharomyces cerevisiae. 总被引:12,自引:4,他引:8
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K Shirahige T Iwasaki M B Rashid N Ogasawara H Yoshikawa 《Molecular and cellular biology》1993,13(8):5043-5056
We have reported the isolation of linking clones of HindIII and EcoRI fragments, altogether spanning a 230-kb continuous stretch of chromosome VI. The presence or absence of autonomously replicating sequence (ARS) activities in all of these fragments has been determined by using ARS searching vectors containing CEN4. Nine ARS fragments were identified, and their positions were mapped on the chromosome. Structures essential for and/or stimulative to ARS activity were determined for the ARS fragments by deletions and mutations. The organization of functional elements composed of core and stimulative sequences was found to be variable. Single core sequences were identified in eight of nine ARSs. The remaining ARS (ARS603) essential element is composed of two core-like sequences. The lengths of 3'- and 5'-flanking stimulative sequences required for the full activity of ARSs varied from ARS to ARS. Five ARSs required more than 100 bp of the 3'-flanking sequence as stimulative sequences, while not more than 79 bp of the 3' sequence was required by the other three ARSs. In addition, five ARSs had stimulative sequences varying from 127 to 312 bp in the 5'-flanking region of the core sequence. In general, these stimulative activities were correlated with low local delta Gs of unwinding, suggesting that the low local delta G of an ARS is an important element for determining the efficiency of initiation of replication of ARS plasmids. 相似文献
42.
Perception of several bitter-tasting compounds was tested in52 subjects. Stable individual differences in the perceivedintensity of the bitterness of suprathreshold concentrationsof quinine sulfate (QSO4) and urea were found. Whereas 18 subjectsjudged selected concentrations of these compounds to be equallybitter, 17 found QSO4 to be more bitter than urea, and 17 foundurea to be more bitter than QSO4. These reliable individualdifferences were significantly related to threshold sensitivityto QSO4; that is, individuals who perceived QSO4 to be moreintense than urea at suprathreshold concentrations also hadlower QSO4 thresholds than did those who perceived urea to bemore intense than QSO4. There appeared to be no relationshipbetween the relative perceived intensities of these compoundsand rating of the bitterness of PROP (6-n-propylthiouracil).However, QSO4-sensitive individuals tended to find the bitternessof suprathreshold caffeine and sucrose octaacetate to be greaterthan that of suprathreshold magnesium sulfate, whereas the reversewas true for urea-sensitive individuals. This pattern parallelsthe pattern of cross-adaptation among these compounds reportedby other investigators. These results are consistent with theexistence of multiple bitter transduction sequences and suggestthat individual differences in response to various bitter compoundsmay reflect differences in teh relative availability of specifictransduction sequences. 相似文献
43.
Sakaba Tomoka Soejima Akiko Fujii Shinji Ikeda Hajime Iwasaki Takaya Saito Hiroaki Suyama Yoshihisa Matsuo Ayumi Kozhevnikov Andrey E. Kozhevnikova Zoya V. Wang Hongfeng Wang Siqi Pak Jae-Hong Fujii Noriyuki 《Journal of plant research》2023,136(4):437-452
Journal of Plant Research - A group of temperate grassland plant species termed the “Mansen elements” occurs in Japan and is widely distributed in the grasslands of continental East... 相似文献
44.
S Ito A Iwasaki J Syundo Y Tamura S Kishi H Mori K Ii Y Matsuda N Katsunuma 《The journal of histochemistry and cytochemistry》1989,37(5):611-615
Human liver guanase was purified and a specific antibody against it was raised in rabbits. The antiserum formed a single precipitin line with human liver extract, and also completely inhibited the activity of the liver enzyme. An immunoblotting study showed that the antibody bound specifically to one band of protein with guanase activity and not to other proteins. Therefore, we concluded that this antiserum against the liver enzyme was suitable for use in immunohistochemical demonstration of guanase. In tissue sections, the immunohistochemical reaction with this antibody was positive in the same locations as the histochemical guanase reaction with DAB (3,3'-diaminobenzidine tetrahydrochloride). 相似文献
45.
Ken-Ichi Iwasaki Rong Zhang Julie H Zuckerman Benjamin D Levine 《Journal of applied physiology》2003,95(4):1575-1583
Occupational or recreational exercise reduces mortality from cardiovascular disease. The potential mechanisms for this reduction may include changes in blood pressure (BP) and autonomic control of the circulation. Therefore, we conducted the present long-term longitudinal study to quantify the dose-response relationship between the volume and intensity of exercise training, and regulation of heart rate (HR) and BP. We measured steady-state hemodynamics and analyzed dynamic cardiovascular regulation by spectral and transfer function analysis of cardiovascular variability in 11 initially sedentary subjects during 1 yr of progressive endurance training sufficient to allow them to complete a marathon. From this, we found that 1) moderate exercise training for 3 mo decreased BP, HR, and total peripheral resistance, and increased cardiovascular variability and arterial baroreflex sensitivity; 2) more prolonged and intense training did not augment these changes further; and 3) most of these changes returned to control values at 12 mo despite markedly increased training duration and intensity equivalent to that routinely observed in competitive athletes. In conclusion, increases in R-wave-R-wave interval and cardiovascular variability indexes are consistent with an augmentation of vagal modulation of HR after exercise training. It appears that moderate doses of training for 3 mo are sufficient to achieve this response as well as a modest hypotensive effect from decreasing vascular resistance. However, more prolonged and intense training does not necessarily lead to greater enhancement of circulatory control and, therefore, may not provide an added protective benefit via autonomic mechanisms against death by cardiovascular disease. 相似文献
46.
A Novel Class of Herbicides (Specific Inhibitors of Imidazoleglycerol Phosphate Dehydratase) 总被引:4,自引:2,他引:2
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Mori I Fonne-Pfister R Matsunaga S Tada S Kimura Y Iwasaki G Mano J Hatano M Nakano T Koizumi S Scheidegger A Hayakawa K Ohta D 《Plant physiology》1995,107(3):719-723
A new mode of herbicidal action was established by finding specific inhibitors of imidazoleglycerol phosphate dehydratase, an enzyme of histidine (His) biosynthesis. Three triazole phosphonates inhibited the reaction of the enzyme with Ki values of 40 [plus or minus] 6.5, 10 [plus or minus] 1.6, and 8.5 [plus or minus] 1.4 nM, respectively, and were highly cytotoxic to cultured plant cells. This effect was completely reversed by the addition of His, proving that the cytotoxicity was primarily caused by the inhibition of His biosynthesis. These inhibitors showed wide-spectrum, postemergent herbicidal activity at application rates ranging from 0.05 to 2 kg/ha. 相似文献
47.
Yoshiaki Iwasaki Hiroyuki Takabatake Marc Monestier Soldano Ferrone 《Immunogenetics》1995,42(2):90-100
The anti-HLA-DQ3 monoclonal antibodies (mAb) KS13, SO1, SO2, SO3, SO4, and SO5 recognize spatially close but distinct antigenic determinants, since they crossinhibit each other in their binding to HLA-DQ3 antigens, but do not share idiotopes recognized in their antigen combining site by syngeneic and anti-id antisera and mAb. Furthermore, mAb SO1, SO3, SO4, and SO5 react also with HLA-DQ allospecificities other than HLA-DQ3. Sequence analysis of the heavy (V
H
) and light (V
L
) chain variable region of the six mAb revealed preferential usage of V
H
36–60 and V
K
12/13 gene families. However, the individual V
H
and V
L
germline gene usage by the six mAb is diverse and the utilization of D, J
H
, and J
L
gene segments is heterogeneous. The diverse usage of V
H
and V
L
gene segments and heterogeneous amino acid sequences of V
H
and V
L
CDR, together with the heterogeneous idiotypic profile, may reflect the complexity of the determinants recognized by the six mAb on HLA-DQ3 antigens. The results we have presented provide for the first time information about the structural basis of the diversity of antibodies recognizing human histocompatibility antigens.The nucleotide sequence data reported in this Papershave been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers L20499, L20957, L20961, L24557, L24558 and L20962, respectively, for V
H
region genes, and L20956, L20958, L24555, L24556, L20959, and L20960, respectively, for V
L
region genes 相似文献
48.
Nucleotide sequence of a Sendai virus genome region covering the entire M gene and the 3'' proximal 1013 nucleotides of the F gene. 总被引:11,自引:4,他引:7
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Y Hidaka T Kanda K Iwasaki A Nomoto T Shioda H Shibuta 《Nucleic acids research》1984,12(21):7965-7973
We determined the sequence of the 2,138 nucleotides in the Sendai virus genome just following the 3' proximal 3,686 nucleotides which we had previously reported (Nucleic Acids Res. 11, 7317-7330, 1983). This covers the entire third gene of 1,173 nucleotides and the 3' proximal 1,013 nucleotides of the fourth gene. Like the NP and P+C genes, both the third and fourth genes start from consensus sequence R1 (3'-UCCCAC(or UA)UUUC) at the 3' end and the third gene terminates with consensus sequence R2 (3'-AUUCUUUUU) at the 5' end. The third gene was identified as M, and the deduced 348 amino acids indicated that the M protein is rich in basic residues and has hydrophobic domains near the C-terminal. The fourth gene, although sequencing is not complete yet, was identified as F, since a large open reading frame found in the gene contains the characteristic sequence of 20 amino acids located at the N-terminal of the F1 protein. Analyses of the amino acid sequence suggested that the structure of the F gene product is NH2-signal peptide-F2-F1-COOH. 相似文献
49.
Terpenoid and acetylenic components not reported previously in Artemisia capillaris have been identified, including p-cymene, 5-phenyl-1, 3-diyne, dehydrofalcarinone and dehydrofalcarinol. The distribution of volatile components in different parts of the plant is described. 相似文献
50.