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71.
Isolation of a LIM15/DMC1 homolog from the basidiomycete Coprinus cinereus and its expression in relation to meiotic chromosome pairing 总被引:1,自引:0,他引:1
Nara T Saka T Sawado T Takase H Ito Y Hotta Y Sakaguchi K 《Molecular & general genetics : MGG》1999,262(4-5):781-789
The Escherichia coli gene recA is essential for homologous recombination and DNA repair, and homologs have been identified in eukaryotes. A basidiomycete,
Coprinus cinereus, which has many advantages for the study of meiosis, was recently reported to have a homolog of one of these, RAD51. In the yeast Saccharomyces, mutations in the RAD5I gene cause defects in both somatic and meiotic cells. Based on this finding, we screened for a meiosis-specific homolog of
recA, equivalent to Lilium LIM15 or Saccharomyces DMC1, in C. cinereus, and isolated a clone containing a 1.2-kb DNA fragment from a cDNA library constructed with Coprinus poly(A)+ RNA isolated from cells undergoing meiosis. The predicted amino acid sequence was 52% identical to the putative gene product
of the lily cDNA clone LIM15 and 61% identical to Saccharomyces DMC1, and showed limited sequence similarity to the products of RAD52, 55, and 57. The synchrony of meiosis in Coprinus provides an ideal system for the investigation of differential gene expression in relation to meiosis and fruiting body development.
Northern analysis indicated that Coprinus LIM15/DMC1 was expressed at meiotic prophase within 8 h after the onset of karyogamy, suggesting that the gene functions mostly at the
stage at which the homologous chromosomes pair, but may not be essential at the point at which they recombine. The gene is
not expressed in somatic cells.
Received: 8 October 1998 / Accepted: 22 July 1999 相似文献
72.
Kezuka Y Kitazaki K Itoh Y Watanabe J Takaha O Watanabe T Nishizawa Y Nonaka T 《Protein and peptide letters》2004,11(4):401-405
We report here on crystallization and preliminary X-ray analysis of plant class I chitinase from rice (OsChia1b). Similar single crystals of full-length OsChia1b were obtained under two independent conditions. The crystals grown under these conditions diffracted up to 2.1 and 2.5 angstroms resolution, respectively, at a synchrotron beamline, and were found to belong to the tetragonal space group P4(3)2(1)2. 相似文献
73.
Katogi R Nakatani Y Shin-i T Kohara Y Inohaya K Kudo A 《Mechanisms of development》2004,121(7-8):861-872
Medaka is an attractive model to study epimorphic regeneration. The fins have remarkable regenerative capacity and are replaced about 14 days after amputation. The formation of blastema, a mass of undifferentiated cells, is essential for regeneration; however, the molecular mechanisms are incompletely defined. To identify the genes required for fin regeneration, especially for blastema formation, we constructed cDNA libraries from fin regenerates at 3 days postamputation and 10 days postamputation. A total of 16,866 expression sequence tags (ESTs) were sequenced and subjected to BLASTX analysis. The result revealed that about 60% of them showed strong matches to previously identified proteins, and major signaling molecules related to development, including FGF, BMP, Wnt, Notch/Delta, and Ephrin/Eph signaling pathways were isolated. To identify novel genes that showed specific expression during fin regeneration, cDNA microarray was generated based on 2900 independent ESTs from each library which had no sequence similarity to known proteins. We obtained 6 candidate genes associated with blastema formation by gene expression pattern screening in competitive hybridization analyses and in situ hybridization. Olrfe16d23 and olrfe14k04 were expressed only in early regenerating stages when blastema formation was induced. The expression of olrf5n23, which encodes a novel signal peptide, was detected in wound epidermis throughout regeneration. Olrfe23l22, olrfe20n22, and olrfe24i02 were expressed notably in the blastema region. Our study has thus identified the gene expression profiles and some novel candidate genes to facilitate elucidation of the molecular mechanisms of fin regeneration. 相似文献
74.
75.
Kondo K 《BioFactors (Oxford, England)》2004,22(1-4):303-310
It has been demonstrated that the light-to-moderate consumption of alcoholic beverages is associated with significant reductions in all-cause and particularly cardiovascular mortality. While the inverse association between red-wine consumption and cardiovascular risk is globally recognized as the French paradox, many epidemiological studies have concluded that beer and red wine are equally beneficial. Moderate alcohol intake improves lipoprotein metabolism and lowers cardiovascular mortality risk. The question now is whether additional health benefits associated with the non-alcohol components in beer may be expected. This article summarizes the results of the latest studies on the health benefits of beer while referring to our recent results, which demonstrate the preventive effects of beer and its components on lifestyle-related diseases. A series of studies using animal models have shown that beer may prevent carcinogenesis and osteoporosis; beer provides plasma with significant protection from oxidative stress; and isohumulones, the bitter substances derived from hops, may prevent and improve obesity and type-2 diabetes, improve lipid metabolism, and suppress atherosclerosis. Further studies are needed to clarify the components in addition to isohumulones that are responsible for these beneficial effects of beer, and the underlying mechanisms must be addressed. 相似文献
76.
Ichinose M Saito M Ogawa T Hayashi K Kondo N Nishiyasu T 《American journal of physiology. Heart and circulatory physiology》2004,287(5):H2147-H2153
We tested the hypothesis that orthostatic stress would modulate the arterial baroreflex (ABR)-mediated beat-by-beat control of muscle sympathetic nerve activity (MSNA) in humans. In 12 healthy subjects, ABR control of MSNA (burst incidence, burst strength, and total activity) was evaluated by analysis of the relation between beat-by-beat spontaneous variations in diastolic blood pressure (DAP) and MSNA during supine rest (CON) and at two levels of lower body negative pressure (LBNP: -15 and -35 mmHg). At -15 mmHg LBNP, the relation between burst incidence (bursts per 100 heartbeats) and DAP showed an upward shift from that observed during CON, but the further shift seen at -35 mmHg LBNP was only marginal. The relation between burst strength and DAP was shifted upward at -15 mmHg LBNP (vs. CON) and further shifted upward at -35 mmHg LBNP. At -15 mmHg LBNP, the relation between total activity and DAP was shifted upward from that obtained during CON and further shifted upward at -35 mmHg LBNP. These results suggest that ABR control of MSNA is modulated during orthostatic stress and that the modulation is different between a mild (nonhypotensive) and a moderate (hypotensive) level of orthostatic stress. 相似文献
77.
Tanaka R Ono T Sato S Nakada T Koizumi F Hasegawa K Nakagawa K Okumura H Yamashita T Ohtsuka M Asagoe K Yamasaki O Noguchi Y Iwatsuki K Nakayama E 《Microbiology and immunology》2004,48(4):339-345
The TSGA10 gene was originally isolated in normal testis by differential mRNA display. TSGA10 is located on chromosome 2q11.2 and consists of 19 exons extending over 3 kb. TSGA10 mRNA expression was investigated in normal and malignant tissues using quantitative real-time RT-PCR. It was predominantly expressed in the testis in adult normal tissues. In malignant tissues, TSGA10 was over-expressed in 4 of 20 hepatocellular carcinomas (HCC), 1 of 20 colon cancers, 7 of 20 ovarian cancers, 3 of 20 prostate cancers, 1 of 21 malignant melanomas, and 8 of 21 bladder cancers. Serological analysis revealed that 3 out of 346 patients with various types of cancer possessed antibody against recombinant TSGA10 protein. They included 2 patients with hepatocellular carcinoma and a patient with malignant melanoma. 相似文献
78.
Funatogawa K Hayashi S Shimomura H Yoshida T Hatano T Ito H Hirai Y 《Microbiology and immunology》2004,48(4):251-261
Helicobacter pylori is a major etiological agent in gastroduodenal disorders. In this study, we isolated 36 polyphenols and 4 terpenoids from medicinal plants, and investigated their antibacterial activity against H. pylori in vitro. All hydrolyzable tannins tested demonstrated promising antibacterial activity against H. pylori. Monomeric hydrolyzable tannins revealed especially strong activity. Other compounds demonstrated minimal antibacterial activity with a few exceptions. A monomeric hydrolyzable tannin, Tellimagrandin I demonstrated time- and dose-dependent bactericidal activity against H. pylori in vitro. On the other hand, hydrolyzable tannins did not affect the viability of MKN-28 cells derived from human gastric epithelium. Hydrolyzable tannins, therefore, have potential as new and safe therapeutic regimens against H. pylori infection. Furthermore, we investigated effects of hydrolyzable tannins on lipid bilayer membranes. All the hydrolyzable tannins tested demonstrated dose-dependent membrane-damaging activity. However, it remains to be elucidated whether their membrane-damaging activity directly contributes to their antibacterial action. 相似文献
79.
Plant-specific microtubule-associated protein SPIRAL2 is required for anisotropic growth in Arabidopsis 下载免费PDF全文
Shoji T Narita NN Hayashi K Hayashi K Asada J Hamada T Sonobe S Nakajima K Hashimoto T 《Plant physiology》2004,136(4):3933-3944
In diffusely growing plant cells, cortical microtubules play an important role in regulating the direction of cell expansion. Arabidopsis (Arabidopsis thaliana) spiral2 (spr2) mutant is defective in directional cell elongation and exhibits right-handed helical growth in longitudinally expanding organs such as root, hypocotyl, stem, petiole, and petal. The growth of spr2 roots is more sensitive to microtubule-interacting drugs than is wild-type root growth. The SPR2 gene encodes a plant-specific 94-kD protein containing HEAT-repeat motifs that are implicated in protein-protein interaction. When expressed constitutively, SPR2-green fluorescent protein fusion protein complemented the spr2 mutant phenotype and was localized to cortical microtubules as well as other mitotic microtubule arrays in transgenic plants. Recombinant SPR2 protein directly bound to taxol-stabilized microtubules in vitro. Furthermore, SPR2-specific antibody and mass spectrometry identified a tobacco (Nicotiana tabacum) SPR2 homolog in highly purified microtubule-associated protein fractions from tobacco BY-2 cell cultures. These results suggest that SPR2 is a novel microtubule-associated protein and is required for proper microtubule function involved in anisotropic growth. 相似文献
80.
Komatsu M Chiba T Tatsumi K Iemura S Tanida I Okazaki N Ueno T Kominami E Natsume T Tanaka K 《The EMBO journal》2004,23(9):1977-1986
Several studies have addressed the importance of various ubiquitin-like (UBL) post-translational modifiers. These UBLs are covalently linked to most, if not all, target protein(s) through an enzymatic cascade analogous to ubiquitylation, consisting of E1 (activating), E2 (conjugating), and E3 (ligating) enzymes. In this report, we describe the identification of a novel ubiquitin-fold modifier 1 (Ufm1) with a molecular mass of 9.1 kDa, displaying apparently similar tertiary structure, although lacking obvious sequence identity, to ubiquitin. Ufm1 is first cleaved at the C-terminus to expose its conserved Gly residue. This Gly residue is essential for its subsequent conjugating reactions. The C-terminally processed Ufm1 is activated by a novel E1-like enzyme, Uba5, by forming a high-energy thioester bond. Activated Ufm1 is then transferred to its cognate E2-like enzyme, Ufc1, in a similar thioester linkage. Ufm1 forms several complexes in HEK293 cells and mouse tissues, revealing that it conjugates to the target proteins. Ufm1, Uba5, and Ufc1 are all conserved in metazoa and plants but not in yeast, suggesting its potential roles in various multicellular organisms. 相似文献