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91.
Tanigawa M Miyamoto K Kobayashi S Sato M Akutsu H Okabe M Mekada E Sakakibara K Miyado M Umezawa A Miyado K 《Molecular reproduction and development》2008,75(1):150-155
Tetraspanin CD81 is closely homologous in amino acid sequence with CD9. CD9 is well known to be involved in sperm-egg fusion, and CD81 has also been reported to be involved in membrane fusion events. However, the function of CD81 as well as that of CD9 in membrane fusion remains unclear. Here, we report that disruption of the mouse CD81 gene led to a reduction in the fecundity of female mice, and CD81-/- eggs had impaired ability to fuse with sperm. Furthermore, we demonstrated that when CD81-/- eggs were incubated with sperm, some of the sperm that penetrated into the perivitelline space of CD81-/- eggs had not yet undergone the acrosome reaction, indicating that the impaired fusibility of CD81-/- eggs may be in part caused by failure of the acrosome reaction of sperm. In addition, we showed that CD81 was highly expressed in granulosa cells, somatic cells that surround oocytes. Our observations suggest that there is an interaction between sperm and CD81 on somatic cells surrounding eggs before the direct interaction of sperm and eggs. Our results may provide new clues for clarifying the cellular mechanism of the acrosome reaction, which is required for sperm-egg fusion. 相似文献
92.
Takao Suzuki Maki Moritani Masayasu Yoshino Mitsuhiro Kagami Shoji Iwasaki Kouichi Nishimura Masahiko Akamatsu Masato Kobori Hitoshi Matsushime Masao Kotoh Kiyoshi Furuichi Mitsuo Itakura 《Mammalian genome》2008,19(1):15-25
When the homozygous active form of porcine TGF-β1 transgene (Tgf/Tgf) (under control of the rat glucagon promoter) is introduced into the nonobese diabetic mouse (NOD) genetic background, the
mice develop endocrine and exocrine pancreatic hypoplasia, low serum insulin concentrations, and impaired glucose tolerance.
To identify genetic modifiers of the diabetic phenotypes, we crossed hemizygous NOD-Tgf with DBA/2J mice (D2) or C3H/HeJ mice (C3H) and used the “transgenic mice” for quantitative trait loci (QTL) analysis. Genome-wide
scans of F2-D Tgf/Tgf (D2 × NOD) and F2-C Tgf/Tgf (C3H × NOD), homozygous for the TGF-β1 transgene, identified six statistically significant modifier QTLs: one QTL (Tdn1) in F2-D Tgf/Tgf, and five QTLs (Tcn1 to Tcn5) in F2-C Tgf/Tgf. Tdn1 (Chr 13, LOD = 4.39), and Tcn3 (Chr 2, LOD = 4.94) showed linkage to body weight at 8 weeks of age. Tcn2 (Chr 7, LOD = 4.38) and Tcn4 (Chr 14, LOD = 3.99 and 3.78) showed linkage to blood glucose (BG) concentrations in ipGTT at 30, 0, and 120 min, respectively. Tcn1 (Chr 1, LOD = 4.41) and Tcn5 (Chr 18, LOD = 4.99) showed linkage to serum insulin concentrations in ipGTT at 30 min. Tcn2 includes the candidate gene, uncoupling protein 2 (Ucp2), and shows linkage to Ucp2 mRNA levels in the soleus muscle (LOD = 4.90). Identification of six QTLs for diabetes-related traits in F2-D Tgf/Tgf and F2-C Tgf/Tgf raises the possibility of identifying candidate susceptibility genes and new targets for drug development for human type
2 diabetes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
93.
S. Nagai C. Lian M. Hamaguchi Y. Matsuyama S. Itakura T. Hogetsu 《Molecular ecology resources》2004,4(1):83-85
Outbreaks of paralytic shellfish poisoning caused by the toxic dinoflagellate Alexandrium tamarense (Dinophyceae) are currently a serious problem from an economic and food hygiene point of view throughout the world. We isolated 13 polymorphic microsatellite loci from this species. These loci provided microsatellite markers with high polymorphism ranging from four to 15 alleles per locus and gene diversity between 0.632 and 0.974. The markers are available for more detailed investigations of genetic structure and gene flow of A. tamarense populations. 相似文献
94.
Yotsumoto F Yagi H Suzuki SO Oki E Tsujioka H Hachisuga T Sonoda K Kawarabayashi T Mekada E Miyamoto S 《Biochemical and biophysical research communications》2008,365(3):555-561
Aberrant expression levels of epidermal growth factor receptor (EGFR) and its cognate ligands have been recognized as one of the causes of cancer progression. To investigate the validity of EGFR ligands as targets for cancer therapy, we examined the expression of EGFR ligands and in vitro anti-tumor effects of small interference RNA (siRNA) for EGFR ligands in various cancer cells. HB-EGF expression was dominantly elevated in ovarian, gastric, and breast cancer, melanoma and glioblastoma cells, whereas amphiregulin was primarily expressed in pancreatic, colon, and prostate cancer, renal cell carcinoma and cholangiocarcinoma cells. Transfection of siRNAs for HB-EGF or amphiregulin into these cells significantly increased the numbers of apoptotic cells with attenuation of EGFR and ERK activation. In lung cancer cells, any EGFR ligand was not recognized as a validated target for cancer therapy. These results suggest that HB-EGF and amphiregulin are promising targets for cancer therapy. 相似文献
95.
Kazuo Iwai Katsumi Shibata Hiroshi Taguchi Tadashi Itakura 《Bioscience, biotechnology, and biochemistry》2013,77(11):2095-2101
Quinolinate phosphoribosyltransferase (EC 2.4.2.19) was purified and crystallized from cell-free extracts of Alcaligenes eutrophus nov. subsp. quinoiinicus, IAM 12305 which was isolated in our laboratory from soil. The enzyme was labile in the cold, and all purification steps were performed at room temperature (10~15°C). The crystalline enzyme was certified to be homogeneous by ultracentrifugal analysis and starch-gel electrophoresis. On polyacrylamide gel disc electrophoresis, the crystalline enzyme showed a multiple profile, but it showed a single band by addition of a certain amount of glycerol and 2-mercaptoethanol. The adding effect of these compounds was discussed. 相似文献
96.
We isolated five polymorphic microsatellite loci from the drepanosiphid aphid Tuberculatus quercicola (Matsumura) that is associated with the Daimyo oak, Quercus dentata Thunberg, using the magnetic particles method. The isolated loci were polymorphic, with four to 16 alleles in 40 aphids. Expected heterozygosities ranged from 0.4 to 0.82. These loci can be used to quantify seasonal changes in clonal diversity in the metapopulation and the extent of clonal mixing in the colonies. 相似文献
97.
Eisuke Sato Maho Morita Haruo Ogawa Masato Iwatsuki Rei Hokari Aki Ishiyama Satoshi Ōmura Arihiro Iwasaki Kiyotake Suenaga 《Bioorganic & medicinal chemistry letters》2018,28(3):298-301
Biselyngbyaside, an 18-membered macrolide glycoside from marine cyanobacteria, and its derivatives are known to be sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) inhibitors. Recently, a SERCA orthologue of the malaria parasite, PfATP6, has attracted attention as a malarial drug target. To provide a novel drug lead, we designed new synthetic analogs of biselyngbyolide B, the aglycone of biselyngbyaside, based on the co-crystal structure of SERCA with biselyngbyolide B, and synthesized them using the established synthetic route for biselyngbyolide B. Their biological activities against malarial parasites were evaluated. 相似文献
98.
Many animals prefer small local benefits to large but temporally or spatially distant benefits, and this preference is termed “temporal discounting” or “spatial discounting.” Although temporal discounting has been studied in many taxa, only a limited number of papers have primarily focused on spatial discounting. Here, a mate-choice experiment was conducted using female house crickets (Acheta domesticus) tasked with selecting between a non-attractive local male and an attractive distant male; training procedures were not performed. The results showed that females that had never heard the calling songs of males exhibited spatial discounting behavior. This finding may be key to determining the fundamental differences between temporal and spatial discounting. 相似文献
99.
Takashi Seino Shintaro Kawasaki Mariko Shimokawa Hiroki Tamagawa Kohta Toshimitsu Masayuki Fujii Yuki Ohta Mami Matano Kosaku Nanki Kenta Kawasaki Sirirat Takahashi Shinya Sugimoto Eisuke Iwasaki Junichi Takagi Takao Itoi Minoru Kitago Yuko Kitagawa Takanori Kanai Toshiro Sato 《Cell Stem Cell》2018,22(3):454-467.e6
100.
Kei Yabuki Joji Haratake Yojiro Tsuda Eisuke Shiba Hiroshi Harada Kenji Yorita Kazuyoshi Uchihashi Atsuji Matsuyama Keiji Hirata Masanori Hisaoka 《Biological trace element research》2018,185(1):36-47
Lanthanum (La) carbonate (LC) is one of the most potent phosphate binders that prevents the elevation of serum phosphate levels in patients with end-stage renal diseases undergoing dialysis. LC binds strongly to dietary phosphate and forms insoluble complexes that pass through the gastrointestinal tract. La deposition in patients treated with LC is a recently documented finding particularly observed in gastric mucosa. We herein describe the detailed gastric mucosal lesions in 45 LC-treated patients and address the potential underlying pathologic mechanism using oral LC administration in rats. Microscopically, La deposition, as shown by subepithelial collections of plump eosinophilic histiocytes or small foreign body granulomas containing coarse granular or amorphous inclusion bodies, was found in the gastric mucosa of 44 (97.8%) of the 45 dialysis patients in the study cohort, which was most frequently associated with foveolar hyperplasia (37.8%). Using oral administration of rats with 1000 mg/day LC for 2 or more weeks, La deposition was consistently detectable in the gastric mucosa but not in other organs examined. In addition, various histologic alterations such as glandular atrophy, stromal fibrosis, proliferation of mucous neck cells, intestinal metaplasia, squamous cell papilloma, erosion, and ulcer were demonstrated in the rat model. Thus, orally administered LC can induce mucosal injury, designated here as La gastropathy, which may alter the local environment and result in La deposition in the gastric mucosa, thereby potentially inducing abnormal cell proliferation or neoplastic lesions. 相似文献