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71.
Destruction of cyclin B is required to the mitotic and meiotic cycles. A cyclin-specific ubiquitinating system, including ubiquitin-activating enzyme (E1), is thought to be responsible for cyclin B destruction. Here we present the cloning, sequencing and expression analysis of goldfish, Carassius auratus, E1 from goldfish ovary. The cloned cDNA is 4069 bp long and encodes 1059 amino acids. The deduced amino acid sequence is highly homologous to E1 from other species. Recombinant goldfish E1 could transfer ubiquitin to cyclin-selective ubiquitin-conjugating enzyme. Tissue distribution revealed a single 4.0-kb message ubiquitous among tissues. 相似文献
72.
73.
The sex of Japanese flounder (Paralichthys olivaceus) is easily altered by water temperature or sex steroid hormone treatment during the period of sex determination. We have previously shown that rearing the genetically female larvae at high water temperature caused the suppression of P450 aromatase (P450arom) gene expression in the gonad and phenotypic sex-reversal of the individuals to males (Kitano et al. 1999. J Mol Endocrinol 23:167-176). In the present study, we show that treatment of genetically female larvae with fadrozole (aromatase inhibitor) or 17alpha-methyltestosterone induces sex-reversal as well as suppression of P450arom gene expression. The effect of fadrozole was counteracted by co-administration of estradiol-17beta. Effective periods for fadrozole treatment to induce sex-reversal were similar to those for high water temperature treatment. RT-PCR did not detect P450arom mRNA in gonad of the sex-reversed, phenotypic males. These results indicate that sex-reversal of the genetically female larvae by aromatase inhibitor (or 17alpha-methyltestosterone) may be due to the suppression of P450arom gene expression and the resultant decrease in the amount of estrogen. 相似文献
74.
The process of egg formation in the body cavity of a phytoseiid mite, Phytoseiulus persimilis, was observed to examine fertilization of male eggs. After insemination, one of the ova at the periphery of the ovary began to expand, taking up yolk. Two pronuclei appeared in the expanded egg, located dorsally in the ovary, and yolk granules were formed gradually. After the egg became filled with yolk granules the two pronuclei fused. The egg moved via the narrow entrance at the ventral region into the oviduct, where the eggshell was formed. When the eggshell was complete, and while embryogenesis proceeded, the egg was deposited. In the meantime some ova began to expand sequentially and two joining pronuclei appeared in expanding eggs. The joining pronuclei in the first egg proved male diploidy. This is additional evidence of pseudo-arrhenotoky in this phytoseiid mite species, since the first eggs developed into males. 相似文献
75.
Taishi Higashi Anna Tajima Naoko Ohshita Tatsunori Hirotsu Irhan Ibrahim Abu Hashim Keiichi Motoyama Sawako Koyama Ruriko Iibuchi Shiuhei Mieda Kenji Handa Tomoaki Kimoto Hidetoshi Arima 《AAPS PharmSciTech》2015,16(6):1290-1298
To achieve the potent therapeutic effects of human immunoglobulin G (IgG), highly concentrated formulations are required. However, the stabilization for highly concentrated human IgG is laborious work. In the present study, to investigate the potentials of polypseudorotaxane (PPRX) hydrogels consisting of polyethylene glycol (PEG) and α- or γ-cyclodextrin (α- or γ-CyD) as pharmaceutical materials for highly concentrated human IgG, we designed the PPRX hydrogels including human IgG and evaluated their pharmaceutical properties. The α- and γ-CyDs formed PPRX hydrogels with PEG (M.W. 20,000) even in the presence of highly concentrated human IgG (>100 mg/mL). According to the results of 1H-NMR, powder X-ray diffraction, and Raman microscopy, the formation of human IgG/CyD PPRX hydrogels was based on physical cross-linking arising from their columnar structures. The release profiles of human IgG from the hydrogels were in accordance with the non-Fickian diffusion model. Importantly, the stabilities of human IgG included into the hydrogels against thermal and shaking stresses were markedly improved. These findings suggest that PEG/CyD PPRX hydrogels are useful to prepare the formulation for highly concentrated human IgG.KEY WORDS: cyclodextrin, human IgG, hydrogel, polypseudorotaxane, stability 相似文献
76.
Shin-ichi Takenaka Shinjiro Kaieda Tomotaka Kawayama Masanobu Matsuoka Yoichiro Kaku Takashi Kinoshita Yuki Sakazaki Masaki Okamoto Masaki Tominaga Katsuya Kanesaki Asako Chiba Sachiko Miyake Hiroaki Ida Tomoaki Hoshino 《Biochemistry and Biophysics Reports》2015
The newly characterized cytokine IL-38 (IL-1F10) belongs to the IL-1 family of cytokines. Previous work has demonstrated that IL-38 inhibited Candida albicans-induced IL-17 production from peripheral blood mononuclear cells. However, it is still unclear whether IL-38 is an inflammatory or an anti-inflammatory cytokine. We generated anti-human IL-38 monoclonal antibodies in order to perform immunohistochemical staining and an enzyme-linked immunosorbent assay. While human recombinant IL-38 protein was not cleaved by recombinant caspase-1, chymase, or PR3 in vitro, overexpression of IL-38 cDNA produced a soluble form of IL-38 protein. Furthermore, immunohistochemical analysis showed that synovial tissues obtained from RA patients strongly expressed IL-38 protein. To investigate the biological role of IL-38, C57BL/6 IL-38 gene-deficient (?/?) mice were used in an autoantibody-induced rheumatoid arthritis (RA) mouse model. As compared with control mice, IL-38 (?/?) mice showed greater disease severity, accompanied by higher IL-1β and IL-6 gene expression in the joints. Therefore, IL-38 acts as an inhibitor of the pathogenesis of autoantibody-induced arthritis in mice and may have a role in the development or progression of RA in humans. 相似文献
77.
Sense-overlapping lncRNA as a decoy of translational repressor protein for dimorphic gene expression
Christelle Alexa Garcia Perez Shungo Adachi Quang Dang Nong Nikko Adhitama Tomoaki Matsuura Toru Natsume Tadashi Wada Yasuhiko Kato Hajime Watanabe 《PLoS genetics》2021,17(7)
Long noncoding RNAs (lncRNAs) are vastly transcribed and extensively studied but lncRNAs overlapping with the sense orientation of mRNA have been poorly studied. We analyzed the lncRNA DAPALR overlapping with the 5´ UTR of the Doublesex1 (Dsx1), the male determining gene in Daphnia magna. By affinity purification, we identified an RNA binding protein, Shep as a DAPALR binding protein. Shep also binds to Dsx1 5´ UTR by recognizing the overlapping sequence and suppresses translation of the mRNA. In vitro and in vivo analyses indicated that DAPALR increased Dsx1 translation efficiency by sequestration of Shep. This regulation was impaired when the Shep binding site in DAPALR was deleted. These results suggest that Shep suppresses the unintentional translation of Dsx1 by setting a threshold; and when the sense lncRNA DAPALR is expressed, DAPALR cancels the suppression caused by Shep. This mechanism may be important to show dimorphic gene expressions such as sex determination and it may account for the binary expression in various developmental processes. 相似文献
78.
Hisayuki Oda Yoshinori Hatakeyama Yuuichi Yamamoto Kazuyo Enomoto Tomoaki Shigano Hidetoshi Iwano 《Applied Entomology and Zoology》2014,49(2):213-221
The fungus Beauveria bassiana (Balsamo) Vuillemin has previously been classified using morphological characteristics, but morphology cannot reveal the phylogenetic relationships among conventionally classified strains. High levels of homology have been found in gene sequences among various B. bassiana strains, complicating the determination of their evolutionary relationships. To elucidate phylogenetic relationships among conventionally known Beauveria species, we analyzed 57 major strains of B. bassiana and 3 strains of B. brongniartii (Saccardo) Petch isolated from Japan by analysis of internal transcribed spacer (ITS) sequences and genome profiling (GP) based on temperature gradient gel electrophoresis of random PCR products. The ITS sequence analysis placed the 57 conventional B. bassiana strains into two clusters, B. bassiana and Beauveria pseudobassiana Rehner et Humber. In contrast, GP analysis produced five clusters of B. bassiana strains that included B. pseudobassiana clusters. These results suggested that GP was more accurate than ITS sequence analysis for determining phylogenetic relationships within B. bassiana. In addition, our findings suggested that conventional strains of B. bassiana isolated from Japan include both B. bassiana and B. pseudobassiana groups. 相似文献
79.
Tomoaki Kudo Tohru Hosoyama Makoto Samura Shunsaku Katsura Arata Nishimoto Naruji Kugimiya Yasuhiko Fujii Tao-Sheng Li Kimikazu Hamano 《Biochemical and biophysical research communications》2014
Peripheral blood mononuclear cell (PBMNC) is one of powerful tools for therapeutic angiogenesis in hindlimb ischemia. However, traditional approaches with transplanted PBMNCs show poor therapeutic effects in severe ischemia patients. In this study, we used autograft models to determine whether hypoxic pretreatment effectively enhances the cellular functions of PBMNCs and improves hindlimb ischemia. Rabbit PBMNCs were cultured in the hypoxic condition. After pretreatment, cell adhesion, stress resistance, and expression of angiogenic factor were evaluated in vitro. To examine in vivo effects, we autografted preconditioned PBMNCs into a rabbit hindlimb ischemia model on postoperative day (POD) 7. Preconditioned PBMNCs displayed significantly enhanced functional capacities in resistance to oxidative stress, cell viability, and production of vascular endothelial growth factor. In addition, autologous transplantation of preconditioned PBMNCs significantly induced new vessels and improved limb blood flow. Importantly, preconditioned PBMNCs can accelerate vessel formation despite transplantation on POD 7, whereas untreated PBMNCs showed poor vascularization. Our study demonstrated that hypoxic preconditioning of PBMNCs is a feasible approach for increasing the retention of transplanted cells and enhancing therapeutic angiogenesis in ischemic tissue. 相似文献
80.
Shigero Tamba Rieko Yodoi Kazushi Morimoto Tomoaki Inazumi Mamiko Sukeno Eri Segi-Nishida Yasushi Okuno Gozoh Tsujimoto Shuh Narumiya Yukihiko Sugimoto 《Biochimie》2010
To understand the role of prostaglandin (PG) receptor EP2 (Ptger2) signaling in ovulation and fertilization, we investigated time-dependent expression profiles in wild-type (WT) and Ptger2−/− cumuli before and after ovulation by using microarrays. We prepared cumulus cells from mice just before and 3, 9 and 14 h after human chorionic gonadotropin injection. Key genes including cAMP-related and epidermal growth factor (EGF) genes, as well as extracellular matrix- (ECM-) related and chemokine genes were up-regulated in WT cumuli at 3 h and 14 h, respectively. Ptger2 deficiency differently affected the expression of many of the key genes at 3 h and 14 h. These results indicate that the gene expression profile of cumulus cells greatly differs before and after ovulation, and in each situation, PGE2-EP2 signaling plays a critical role in cAMP-regulated gene expression in the cumulus cells under physiological conditions. 相似文献