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951.
Minoru Tada Akiko Ishii-Watabe Keiko Maekawa Hiromi Fukushima-Uesaka Kouichi Kurose Takuo Suzuki Nahoko Kaniwa Jun-ichi Sawada Nana Kawasaki Takako Eguchi Nakajima Ken Kato Yasuhide Yamada Yasuhiro Shimada Teruhiko Yoshida Takashi Ura Miyuki Saito Kei Muro Toshihiko Doi Nozomu Fuse Takayuki Yoshino Atsushi Ohtsu Nagahiro Saijo Haruhiro Okuda Tetsuya Hamaguchi Yoshiro Saito Yasuhiro Matsumura 《Immunogenetics》2012,64(12):869-877
Fcγ receptor IIa (FcγRIIa) plays an important role in antibody-dependent cellular cytotoxicity and inflammation. Changes in FcγRIIa expression levels or activity caused by genetic polymorphisms in FCGR2A, the gene encoding FcγRIIa, may lead to differences in disease progression as well as efficacy of antibody therapeutics between individuals. In this study, we sequenced the 5′-flanking region along with all exons and their flanking regions of FCGR2A from 111 Japanese subjects. Forty-eight genetic variations were found including 12 novel ones. Beside the well-known functional 497A?>?G (H166R) polymorphism, we detected 818T?>?C (L273P) at 0.005 frequency. Since the functional significance of this polymorphism has not been revealed, we next assessed the functions of the L273P substitution by expressing wild-type and the variant proteins in human Jurkat cells. The L273P variant protein showed similar cell surface expression and IgG-binding properties as the wild-type, but it exhibited a stronger signal transduction activity based on the approximately 2-fold enhancement of tyrosine phosphorylation of FcγRIIa itself. The current results suggest that L273P could have functional significance in the antibody-dependent clinical responses through FcγRIIa. 相似文献
952.
Komori T Doi A Nosaka T Furuta H Akamizu T Kitamura T Senba E Morikawa Y 《The Journal of biological chemistry》2012,287(24):19985-19996
953.
Estimation of fish biomass using environmental DNA 总被引:5,自引:0,他引:5
Environmental DNA (eDNA) from aquatic vertebrates has recently been used to estimate the presence of a species. We hypothesized that fish release DNA into the water at a rate commensurate with their biomass. Thus, the concentration of eDNA of a target species may be used to estimate the species biomass. We developed an eDNA method to estimate the biomass of common carp (Cyprinus carpio L.) using laboratory and field experiments. In the aquarium, the concentration of eDNA changed initially, but reached an equilibrium after 6 days. Temperature had no effect on eDNA concentrations in aquaria. The concentration of eDNA was positively correlated with carp biomass in both aquaria and experimental ponds. We used this method to estimate the biomass and distribution of carp in a natural freshwater lagoon. We demonstrated that the distribution of carp eDNA concentration was explained by water temperature. Our results suggest that biomass data estimated from eDNA concentration reflects the potential distribution of common carp in the natural environment. Measuring eDNA concentration offers a non-invasive, simple, and rapid method for estimating biomass. This method could inform management plans for the conservation of ecosystems. 相似文献
954.
Miyazaki Y Adachi H Katsuno M Minamiyama M Jiang YM Huang Z Doi H Matsumoto S Kondo N Iida M Tohnai G Tanaka F Muramatsu S Sobue G 《Nature medicine》2012,18(7):1136-1141
Spinal and bulbar muscular atrophy (SBMA) is an inherited neurodegenerative disorder caused by the expansion of the polyglutamine (polyQ) tract of the androgen receptor (AR-polyQ). Characteristics of SBMA include proximal muscular atrophy, weakness, contraction fasciculation and bulbar involvement. MicroRNAs (miRNAs) are a diverse class of highly conserved small RNA molecules that function as crucial regulators of gene expression in animals and plants. Recent functional studies have shown the potent activity of specific miRNAs as disease modifiers both in vitro and in vivo. Thus, potential therapeutic approaches that target the miRNA processing pathway have recently attracted attention. Here we describe a novel therapeutic approach using the adeno-associated virus (AAV) vector–mediated delivery of a specific miRNA for SBMA. We found that miR-196a enhanced the decay of the AR mRNA by silencing CUGBP, Elav-like family member 2 (CELF2). CELF2 directly acted on AR mRNA and enhanced the stability of AR mRNA. Furthermore, we found that the early intervention of miR-196a delivered by an AAV vector ameliorated the SBMA phenotypes in a mouse model. Our results establish the proof of principle that disease-specific miRNA delivery could be useful in neurodegenerative diseases. 相似文献
955.
Uebi T Itoh Y Hatano O Kumagai A Sanosaka M Sasaki T Sasagawa S Doi J Tatsumi K Mitamura K Morii E Aozasa K Kawamura T Okumura M Nakae J Takikawa H Fukusato T Koura M Nish M Hamsten A Silveira A Bertorello AM Kitagawa K Nagaoka Y Kawahara H Tomonaga T Naka T Ikegawa S Tsumaki N Matsuda J Takemori H 《PloS one》2012,7(5):e37803
Salt-inducible kinase 3 (SIK3), an AMP-activated protein kinase-related kinase, is induced in the murine liver after the consumption of a diet rich in fat, sucrose, and cholesterol. To examine whether SIK3 can modulate glucose and lipid metabolism in the liver, we analyzed phenotypes of SIK3-deficent mice. Sik3(-/-) mice have a malnourished the phenotype (i.e., lipodystrophy, hypolipidemia, hypoglycemia, and hyper-insulin sensitivity) accompanied by cholestasis and cholelithiasis. The hypoglycemic and hyper-insulin-sensitive phenotypes may be due to reduced energy storage, which is represented by the low expression levels of mRNA for components of the fatty acid synthesis pathways in the liver. The biliary disorders in Sik3(-/-) mice are associated with the dysregulation of gene expression programs that respond to nutritional stresses and are probably regulated by nuclear receptors. Retinoic acid plays a role in cholesterol and bile acid homeostasis, wheras ALDH1a which produces retinoic acid, is expressed at low levels in Sik3(-/-) mice. Lipid metabolism disorders in Sik3(-/-) mice are ameliorated by the treatment with 9-cis-retinoic acid. In conclusion, SIK3 is a novel energy regulator that modulates cholesterol and bile acid metabolism by coupling with retinoid metabolism, and may alter the size of energy storage in mice. 相似文献
956.
We have previously demonstrated that high doses of recombinant human granulocyte colony-stimulating factor (rhG-CSF) induce bone changes characterized by osteoclastic bone resorption and osteogenesis due to intramembranous ossification in rats. In this communication we examined the effects of a pretreatment with 3-amino-1-hydroxypropylidene-1,1-bisphosphonate (AHPrBP), which is a powerful inhibitor of osteoclastic bone resorption, on bone changes induced by rhG-CSF in order to investigate the relation between osteoclastic bone resorption and osteogenesis. AHPrBP (5 mg/kg/day) was subcutaneously given to 6-week-old rats for 2 days. From the following day of the final injection of AHPrBP, rats received a subcutaneous injection of rhG-CSF (1,000 micrograms/kg/day) for 14 days, and the femur and tibia were evaluated histopathologically. By the analysis of peripheral blood leukocyte counts, spleen weights and bone marrow findings, the pretreatment with AHPrBP had no effect on the activation of hematopoiesis related to the major pharmacological activity of rhG-CSF. In the rats treated with rhG-CSF alone, accelerated osteoclastic bone resorption and osteogenesis due to intramembranous ossification were observed in the trabeculae of metaphyseal spongiosa. The accelerated osteoclastic bone resorption induced by rhG-CSF was suppressed by the pharmacological activity of AHPrBP. Furthermore, the osteogenesis induced by rhG-CSF was also suppressed by AHPrBP. These results suggest that the osteogenesis induced by rhG-CSF is a sequential reaction of accelerated osteoclastic bone resorption, and moreover that the main action of rhG-CSF on bone is an acceleration of osteoclastic bone resorption. 相似文献
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