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81.
Kyu-Sang Lim Kyung-Tai Lee Si-Woo Lee Han-Ha Chai Gulwon Jang Ki-Chang Hong Tae-Hun Kim 《Molecular biology reports》2016,43(9):1011-1018
The fibronectin type III and SPRY domain containing 2 (FSD2) on porcine chromosome 7 is considered a candidate gene for pork quality, since its two domains, which were present in fibronectin and ryanodine receptor. The fibronectin type III and SPRY domains were first identified in fibronectin and ryanodine receptor, respectively, which are candidate genes for meat quality. The aim of this study was to elucidate the genomic structure of FSD2 and functions of single nucleotide polymorphisms (SNPs) within FSD2 that are related to meat quality in pigs. Using a bacterial artificial chromosome clone sequence, we revealed that porcine FSD2 consisted of 13 exons encoding 750 amino acids. In addition, FSD2 was expressed in heart, longissimus dorsi muscle, psoas muscle, and tendon among 23 kinds of porcine tissues tested. A total of ten SNPs, including four missense mutations, were identified in the exonic region of FSD2, and two major haplotypes were obtained based on the SNP genotypes of 633 Berkshire pigs. Both haplotypes were associated significantly with intramuscular fat content (IMF, P < 0.020) and moisture percentage (MP, P < 0.002). Moreover, haplotype 2 was associated with meat color, affecting yellowness (P = 0.002). These haplotype effects were further supported by the alteration of putative protein structures with amino acid substitutions. Taken together, our results suggest that FSD2 haplotypes are involved in regulating meat quality including IMF, MP, and meat color in pigs, and may be used as meaningful molecular makers to identify pigs with preferable pork quality. 相似文献
82.
Takamitsu Utsukihara Satoshi Watanabe Atsushi Tomiyama Wen Chai C. Akira Horiuchi 《Journal of Molecular Catalysis .B, Enzymatic》2006,41(3-4):103-109
Reduction of (+)-and (−)-camphorquinones (1a, 1b) by various vegetables (carrot, potato, sweet potato, apple, Japanese radish, cucumber, burdock and onion) gave -hydroxycamphor selectively. Using burdock, (+)-camphorquinone was reduced to give (−)-3S-exo-hydroxycamphor (4a) as major product in high stereoselectivity with high yield. Moreover, 1,2-cyclohexanedione (1c) and 2-methylcyclohexanone (1d) with various vegetables afford enantiomerically pure trans- and/or cis-alcohol, respectively. Various vegetable reduction gave a new idea of a biotechnological process. 相似文献
83.
With four soils differing in K supplying power and with four rice cultivars (Oryza sativa L.) differing in K uptake kinetic parameters, the relationship between K fertilizer application and soil redox status in rhizosphere and; the distribution of ferrous iron and other toxic substances on the root surface and in the rhizosphere; and the effect of K supply on uptake of reduced iron by rice plants have been studied.The results show that K application on K-deficient soils reduced the content of active reducing substances and ferrous iron in the soil, raised the soil redox potential in the rhizosphere, increased the Eh value of rice roots and lowered the content of iron in the rice plants. These effects of K varied with different rice cultivars. When no K fertilizer was applied, active reducing substances and ferrous iron in rhizosphere soils were decreased more by the rice cultivars absorbing K strongly (e.g. Shanyou 64) than by cultivars absorbing K weakly (e.g. Zhongguo 91). Therefore, the diminution of the toxic substances by K application in the weakly K-absorbing cultivars was more significant.The observation of a rhizobox separated by a nylon screen showed that appreciably more iron oxides, compared with the control, were deposited at or adjacent to the root surfaces of the rice plant supplied with K fertilizer, fully demonstrating the relationship between K nutrition and the total oxidizing power of rice plants. According to the distribution of active reducing substances and ferrous iron, the oxidizing range of the rice root extended in K application treatment a few centimeters away from the root plane. K application to rice affected the soil redox status in rhizosphere in many ways. The main effect was an increase of the oxidizing power of the rice root. As a result, the value of soil Eh was increased, the contents of active reducing substances and ferrous iron were lowered, as well as the number of oxygen consuming microorganisms. 相似文献
84.
Balunas MJ Jones WP Chin YW Mi Q Farnsworth NR Soejarto DD Cordell GA Swanson SM Pezzuto JM Chai HB Kinghorn AD 《化学与生物多样性》2006,3(8):897-915
In an attempt to determine the relationships between the plant profiles (country of collection, taxonomy, plant part) and the compound classes isolated with cytotoxic activity against a panel of human tumor cell lines, the data compiled from a 15-year anticancer drug-discovery project were subjected to an analysis of variance (ANOVA). The results indicate significant trends in cytotoxic activity relative to collection location, taxonomy, plant part, and compound classes isolated. Plant collections were made in tropical forests in six countries, with collections from Ecuador resulting in higher activity than those from Indonesia and Peru. Interestingly, collections from Florida were not statistically different than those from the countries with higher biodiversity. One hundred and forty-five families were represented in the collections, with the Clusiaceae, Elaeocarpaceae, Meliaceae, and Rubiaceae having low ED50 (half maximal effective dose) values. Especially active genera included Aglaia, Casearia, Exostema, Mallotus, and Trichosanthes. Roots and below-ground plant materials were significantly more active than above-ground materials. Cucurbitacins, flavaglines, anthraquinones, fatty acids, tropane alkaloids, lignans, and sesquiterpenoids were significantly more active than xanthones and oligorhamnosides. The results from this study should serve as a guide for future plant collection endeavors for anticancer drug discovery. 相似文献
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87.
Abscisic acid plays an important role in the regulation of strawberry fruit ripening 总被引:10,自引:0,他引:10
The plant hormone abscisic acid (ABA) has been suggested to play a role in fruit development, but supporting genetic evidence has been lacking. Here, we report that ABA promotes strawberry (Fragaria ananassa) fruit ripening. Using a newly established Tobacco rattle virus-induced gene silencing technique in strawberry fruit, the expression of a 9-cis-epoxycarotenoid dioxygenase gene (FaNCED1), which is key to ABA biosynthesis, was down-regulated, resulting in a significant decrease in ABA levels and uncolored fruits. Interestingly, a similar uncolored phenotype was observed in the transgenic RNA interference (RNAi) fruits, in which the expression of a putative ABA receptor gene encoding the magnesium chelatase H subunit (FaCHLH/ABAR) was down-regulated by virus-induced gene silencing. More importantly, the uncolored phenotype of the FaNCED1-down-regulated RNAi fruits could be rescued by exogenous ABA, but the ABA treatment could not reverse the uncolored phenotype of the FaCHLH/ABAR-down-regulated RNAi fruits. We observed that down-regulation of the FaCHLH/ABAR gene in the RNAi fruit altered both ABA levels and sugar content as well as a set of ABA- and/or sugar-responsive genes. Additionally, we showed that exogenous sugars, particularly sucrose, can significantly promote ripening while stimulating ABA accumulation. These data provide evidence that ABA is a signal molecule that promotes strawberry ripening and that the putative ABA receptor, FaCHLH/ABAR, is a positive regulator of ripening in response to ABA. 相似文献
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目的和方法:比较自发性高血压大鼠(SHR)和对照(WKY)大鼠心脏和主动脉丝裂素活化蛋白激酶磷酸酶-1(MKP-1)及细胞外信号调节激酶(ERK-1)的表达,并观察用磷酸钙共沉淀方法转染MKP-1基因对血管紧张素Ⅱ(Ang Ⅱ)刺激平滑肌细胞(VSMC)^3H-胸腺叫啶(^3H-TdR)掺入的影响,以探讨MKP-1在细胞增殖中的调节作用。结果:①与WKY大鼠相比,SHR心脏和主动脉MKP-1呈低表达,分别降低53%和45%(P均<0.01);而SHR心脏和主动脉ERK-1呈明显高表达(P均<0.01),SHR心脏和主动脉ERK-1与MKP-1蛋白比值明显高于WKY。②AngⅡ 10^-7mol/L刺激VSMC增殖较对照组增加257%(P<0.01),转染野生型MKP-1基因细胞可使AngⅡ刺激的^3H-TdR掺入较未转染的细胞降低63%(P<0.05),转染突变型MKP-1基因和转染空载体的VSMC对AngⅡ的刺激与单纯AngⅡ组相比无明显抑制作用(P>0.05)。结论:SHR心血管组织中促增殖肥大的ERK-1表达较其失活的MKP-1占优势,并且MKP-1可显著抑制AngⅡ的VSMC增殖。 相似文献