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11.
Summary A ligninase gene has been cloned from a Phanerochaete chrysosporium genomic DNA library. Nucleotide sequencing of the gene has revealed that the ligninase structural gene contains 1116 bp of the protein-encoding sequence, of which 84 bp encode the signal peptide. The protein-encoding sequence is interrupted by eight introns which conform to the universal G-T/A-G splicing rule observed for the 3 and 5 intron boundaries. The putative eukaryotic regulatory sequences, i.e. CAAT and TATA box-like sequences, are present in the 5 flanking region.  相似文献   
12.
Microtubule-associated protein (MAP) 2 was purified from the microtubule fraction of mouse brain by heat treatment and BioGel A-5m gel filtration. The purified preparation showed a single protein band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis using both a gradient gel (3.75-12.5%) and a low-percentage gel (5%), a finding indicating that MAP2B was absent under the conditions used. Amino acid analysis revealed that mouse MAP2 was an acidic protein with an isoelectric point (pI 4.5) and amino acid composition similar to those of porcine brain MAP2. Immunoblot analysis indicated that the antigens that reacted with MAP2 antiserum were present in large quantities in mouse brain. However, we also found a weak reaction in various tissues other than brain, and the major antigens involved were recognized to be common molecular species with the same molecular mass, 162 and 170 kilodaltons. Using antiserum against mouse brain MAP2, the developmental localization patterns of MAP2 in the mouse cerebellar cortex were studied by immunohistochemistry. MAP2 was mainly localized in the neuronal cells throughout development, with the expression in Purkinje cell dendrites being especially remarkable in the growth of arborization from postnatal day 3 to day 20. At the mature stage, the reaction was strong in the dendritic tree but very weak in the proximal dendrites and cell bodies.  相似文献   
13.
S-Glycoproteins (S-locus-specific glycoproteins) in Brassicaspecies are present only in stigmas and thought to play an importantrole in self-incompatibility system. The stigma extract containsalso several other glycoproteins reacting with the antiserumto S-glycoproteins, among which some glycoproteins from S8S8-and S9S9-homozygotes have the same pI value. Both of the glycoproteinswhich were tentatively termed NS8- and NS8S9-glycoproteins,respectively, were isolated and analyzed. Those were revealedto be identical. Its amino acid sequence was homologous withthe S-glycoproteins in Brassica species. The NS-glycoproteinswere expressed at the same time and only in stigma as S-glycoproteins. (Received July 19, 1988; Accepted September 7, 1988)  相似文献   
14.
To isolate and identify the plasma factor which stimulates prostaglandin I 2 production by rat aortic ring, a human plasma fraction which showed a major stimulating activity on prostaglandin I 2 production was purified by ultrafiltrate, Sephadex G-10 gel filtration and QAE-Sephadex column chromatography. The purified plasma factor was identified as acid by its ultraviolet and infrared absorption spectroscopy, and 1H nmr and 13C nmr spectroscopy. The stimulating activity of the purified plasma factor and that of authentic uric acid coincided with each other. The stimulating potency of uric acid at its physiological concentration in human plasma (about 50 μg/ml) was half of the deproteinized human plasma, and was about 30 fold stronger than that of L-tryptophan, a cofactor of prostaglandin hyperoxidase.  相似文献   
15.
16.
Summary Northern blot analysis of glucose-grown and starch-grown mycelia of Aspergillus oryzae R11340 was conducted using the cloned Taka-amylase A (TAA) gene as a probe. The amount of mRNA homologous to the TAA gene was increased when this fungus was grown with starch as a sole carbon source. In order to analyze the induction mechanism, we inserted the Escherichia coli uidA gene encoding -glucuronidase (GUS) downstream of the TAA promoter and introduced the resultant fusion gene into the A. oryzae genome. Production of a functional GUS protein was induced by starch, but not by glucose. When the effects of various sugars on expression of the fusion gene were examined, the results suggested that the expression of the fusion gene was under control of the TAA gene promoter.  相似文献   
17.
Intraspecific nest usurpation by foundresses was studied in 2 haplometrotic (solitary founding) species of different subgenera,Polistes (P.) riparius andP. (Polistella) snelleni, in areas where they cohabited. The overall probability for a nest to be usurped by a foreign foundress during the season was about twice as large inP. snelleni as inP. riparius. In both, however, probability of usurpation was largest on late pre-emergence nests, or in late June and early July. InP. riparius, all the usurpers of known origins were those foundresses that had lost their pre-emergence nests to destruction probably by some vertebrates; inP. snelleni, some usurpers had the same history as above, while the others had lost many of all larvae to predation by unknown agents before worker emergence. Usurpers of both species destroyed eggs and younger larvae to much greater extents than older larvae or pupae, and they produced fewer numbers of reproductives in comparison with non-usurping foundresses. We concluded that usurpation behavior has been maintained despite its relatively low productivity because renesting would lead to even lower or no reproductive production.  相似文献   
18.
Six independent rat hybridoma cell lines producing monoclonal antibodies to human subgroup C adenovirus early region 1A (E1A) proteins were isolated. Competition binding experiments revealed that each of the monoclonal antibodies was directed against the same epitope or overlapping cluster of epitopes on the E1A proteins. Viral E1A deletion mutants and deleted forms of E1A proteins expressed in Escherichia coli were used to localize the antibody recognition sites to sequences between amino acids 23 and 120, encoded within the first exon of the E1A gene. Similarly, polyclonal antisera raised against the trpE-E1A fusion protein, as well as against the native, biologically active E1A protein, were also directed primarily against this immunodominant region.  相似文献   
19.
To evaluate the relative contributions of the ovarian inhibin and estradiol-17 beta (E) on the regulation of FSH secretion, inhibin and E in ovarian venous plasma (OVP) and FSH and LH in peripheral plasma were simultaneously measured using superovulating rats with special reference to follicular maturation. By the transplantation of a pituitary gland from adult male rats under the kidney capsule between 1100 and 1200 hr on diestrus-1 in cyclic rats, superovulation was successfully induced on the morning of the next estrus without any additional treatment with human chorionic gonadotropin (hCG). The number of maturing follicles capable of ovulating in response to hCG significantly increased at 12 hours after the grafting as compared with sham-operated controls and further increases occurred until the afternoon of proestrus. In the superovulating rat, first and second surges of FSH were completely blocked and an LH surge was also partially suppressed during the periovulatory period when surges of FSH and LH were normally observed in controls. Contents of FSH as well as LH in the animal's own pituitary gland were suppressed significantly after the grafting as compared with controls. A marked increase in inhibin activity in OVP of rats with a pituitary transplant occurred concomitantly with an increase in the number of follicles capable of ovulating whereas E levels in OVP did not so. Inhibin activity in OVP at each point was much higher in the pituitary grafted rats than in controls but this was not true for E levels. These results suggest that ovarian inhibin derived from the maturing follicles rather than E may be a primary factor for regulation of FSH secretion, and high levels of endogenous inhibin can suppress synthesis of LH as well as FSH in the pituitary gland of the female rat.  相似文献   
20.
Phospholipid classes that included plasmalogens of erythrocyte membranes in seven myotonic dystrophy (MyD) patients and seven normal controls were analyzed by HPLC. No significant difference in phospholipid classes was found between patients with MyD and normal controls, but there was a visible difference in peak profiles of compounds of the phosphatidylethanolamine class. In the study of plasmalogens, we used two preparation methods: exposure to HCl and deacylation with mild alkaline. The area ratio of the plasmalogen form to the diacyl form in the phosphatidylethanolamine class of MyD erythrocyte membranes was significantly lower than that of normal controls. Fatty acid analyses showed that fatty acids of both phosphatidylethanolamine subclasses have less unsaturation in MyD.  相似文献   
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