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91.
92.
Yuriko Osakabe Kazuya Nanto Hiroko Kitamura Shinya Kawai Yuki Kondo Tomoyuki Fujii Keiji Takabe Yoshihiro Katayama Noriyuki Morohoshi 《Planta》1996,200(1):13-19
The polypeptide encoded by the partial fragment of cDNA of phenylalanine ammonia-lyase (PAL; EC 4.3.1.5), PALcDNAl (Osakabe et al., 1995, Plant Sci. 105: 217–226), isolated from Populus kitakamiensis (P. sieboldii x P. grandidentata), was expressed in Escherichia coli cells. The polypeptide was purified and an antiserum raised against it. The antiserum recognized a protein of 77 kDa on nitrocellulose blots after sodium dodecyl sulfate-poly-acrylamide gel electrophoresis of total protein and the partially purified PAL protein from P. kitakamiensis. Moreover,the antiserum recognized a protein on the blot after non-denaturing polyacrylamide gel electrophoresis of P. kitakamiensis proteins and this protein had PAL activity. Furthermore, the antibody inhibited PAL activity of extracts from stem tissues. These results showed that the antiserum against the partial PAL peptide recognized only the PAL subunits in extracts of P. kitakamiensis. Immunolocalization studies of P. kitakamiensis tissues revealed that the PAL protein was specifically localized in the xylem and the phloem fibers and no immunogold signal was found in the epidermis, the cortex, the pith, or the cambium of either stems or leaves.Abbreviations IgG
immunoglobulin G
- IPTG
isopropylthio--d-galactoside
- PAL
phenylalanine ammonia-lyase
The authors thank Dr. Kunio Hata of Nippon Paper Industries Co., Ltd. (Japan) for supplying P. kitakamiensis. This work was supported in part by a grant-in-aid for Scientific Research from the Ministry of Education, Science and Culture of Japan (No. 07406008). 相似文献
93.
Carrot (Daucus carota L.) embryogenic callus (EC) loses its embryogenic competence and becomes nonembryogenic callus (NC) during long-term culture. With the loss of embryogenic competence, the cell clusters become smaller and the extent of intercellular attachments is reduced. Pectic fractions prepared from EC and NC were separated into two subfractions by gel filtration. A difference in sugar composition between EC and NC was found only in the high-molecular-mass (ca. 1300 kDa) subfraction, and the ratio of the amount of arabinose to that of galactose (Ara/Gal) was strongly and positively correlated with the size of cell clusters in several different cultures. From the results of sugar-composition and methylation analyses, and the results of treatment with exo-arabinanase, models of the neutral sugar chains of pectins from EC and NC are proposed. Both neutral sugar chains are composed of three regions. The basal region is composed of linearly linked arabinan 5-Araf> moieties in both types of callus. The middle galactan region is composed of 6-linked galactose, some of which branches at the 3 and 4 positions, and this region is larger and more frequently branched in NC than in EC. Finally, the terminal arabinan region is composed of 5-linked arabinose, branched at the 3 position, and the size of the terminal arabinan is larger in EC than in NC. The significance of the neutral sugar chains of pectins in the interaction of cell wall components and intercellular attachment is discussed.Abbreviations Ara/Gal
ratio (w/w) of the amount of arabinose to that of galactose
- EC
embryogenic callus
- NC
non-embryogenic callus
- T-Araf
terminal arabinose
The authors are grateful to Dr. Naoto Shibuya of the National Institute of Agrobiological Resources for his gift of exo-arabinanase. 相似文献
94.
cDNA cloning and tissue-specific expression of a novel basic helix-loop-helix/PAS factor (Arnt2) with close sequence similarity to the aryl hydrocarbon receptor nuclear translocator (Arnt). 总被引:11,自引:1,他引:10
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95.
Yoko Takita Yoshikazu Ohya Yasuhiro Anraku 《Molecular genetics and genomics : MGG》1995,246(3):269-281
Genetic screening of Saccharomyces cerevisiae mutants defective in Ca2+ homeostasis identified cls2, which exhibits a specific Ca2+-sensitive growth phenotype. We describe here the CLS2 gene and a multicopy suppressor (named BCL21, for bypass of CLS2) of the cls2 mutation. The CLS2 gene encodes a polypeptide of 410 amino acid residues, and its hydropathy profile indicates that the predicted Cls2 protein (Cls2p) contains ten putative membrane spanning regions. Immunofluorescent staining of the yeast cells expressing epitopetagged Cls2p suggests that Cls2p is localized to endoplasmatic reticulum (ER) membrane. A cls2 disruption strain is viable, but shows a Ca2+-sensitive phenotype like the original cls2 mutants. BCL21 suppresses the cls2 disruption mutation, indicating that the multicopy suppression does not require the Cls2p. Suppression of cls2 was observed even after introduction of a singlecopy plasmid harboring BCL21. The BCL21 gene encodes a protein of 382 amino acid residues and is identical to the SUR1 gene. sur1 was originally isolated as a suppressor of rvs161, which has reduced viability in nutrient starvation conditions. Possible mechanisms of the multicopy suppression are discussed. 相似文献
96.
97.
Yoshikazu Ueno 《Journal of Ethology》1994,12(2):81-87
When the tufted capuchin urinates, it frequently performs “urine-washing”. Previous studies have proposed several hypotheses
about this behavior. This study investigated 1) whether the tufted capuchin can distinguish the urine odor of conspecific
individuals from other groups, and 2) whether the capuchins can distiguish conspcific urine odor of from that of other species.
When an odor bar that had been prepared in conspecific other group's cage was presented, the response (sniffing, licking,
or biting) was significantly greater than that to any other odors, including that of the home group, 5 other species, or a
neutral odor. This tendency was stronger in males than in females. and suggests that the tufited capuchin is able to discriminate
its home group's urine odor from that of the other groups. This monkey may also discriminate its own species from others by
urine odor. The sex difference of the response to the odor bar may be the result of differences in social role between males
and females. These results support the idea that the tufted capuchin may use olfaction for social communication. 相似文献
98.
99.
Fumio Yamazaki Ryoko Sone Nobuharu Fujii Haruo Ikegami 《International journal of biometeorology》1993,37(4):212-217
Based on the hypothesis that the relation between sweating rate and body temperature should be different during exercise and rest after exercise, we compared the sweating response during exercise and recovery at a similar body temperature. Healthy male subjects performed submaximal exercise (Experiment 1) and maximal exercise (Experiment 2) in a room at 27° C and 35% relative humidity. During exercise and recovery of 20 min after exercise, esophageal temperature (Tes), mean skin temperature, mean body temperature (
), chest sweating rate (
), and the frequency of sweat expulsion (F
SW) were measured. In both experiments,
andF
SW were clearly higher during exercise than recovery at a similar body temperature (Tes,
).
was similar during exercise and recovery, or a little less during the former, at a similarF
SW. It is concluded that the sweating rate during exercise is greater than that during recovery at the same body temperature, due to greater central sudomotor activity during exercise. The difference between the two values is thought to be related to non-thermal factors and the rate of change in mean skin temperature. 相似文献
100.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Kazuno Imai Yoshikazu Kandori Akira Ishizuka Atsushi Osada 《European journal of applied physiology and occupational physiology》1993,67(4):354-359
We have examined the nonparallel changes in tampanic membrane temperatures (T
ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T
ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T
ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T
ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T
ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T
ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T
ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation. 相似文献