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991.
992.
The poultry feather color inheritance has been a hot research topic, because the feather color is a kind of important quality character.In this study, we used polyacrylamide gel electrophoresis to detect the polymorphisms of four quail populations of different feather color (China Yellow quail, Black quail, Korean quail, Beijing White quail) of agouti-related protein gene (Agrp) exon Ⅰ, so as to investigate the relationship of Agrp exon I with quail plumage color, and to provide reference for the breeding and production of quail.The results showed that two alleles were detected in the Agrp exon Ⅰ of China Yellow quail, Black quail, Korean quail, Beijing White quail populations,and expressed by A and B, respectively. Frequency of allele A in Beijing White quail was up to 0.9500. The frequency of B allele in Korean quail was the highest, reaching 0.3392, in Beijing White quail genes in the lowest frequency is only 0.0500. The genotype frequency of AA genotype in Beijing White quail was the highest (0.9500), the lowest in Korean quail and Black quail (0.4286). BB genotype was not observed in Beijing White quail. We speculated that it may have a certain relationship between Agrp exon Ⅰ B allele and feather color of quail.  相似文献   
993.
《Journal of plant nutrition》2013,36(12):2817-2829
ABSTRACT

Sulfur deficiency in garlic Allium sativum L. caused a reduction in growth together with chlorosis and necrosis of leaves. Large differences in shoot sulfur and sulphate concentrations between deficient and high sulfur treatments were only observed after 54 days growth. Using the mRNA differential display technique, a novel cDNA was isolated from shoots grown in sulfur depleted nutrient solution for 24 days. This novel cDNA was constitutively expressed in the shoots during further growth in sulfur depleted solution, but it was undetectable following 30 days recovery with sulfur supplementation. The cDNA sequence demonstrated a high degree of identity with a coat protein gene of a garlic latent carlavirus. The results suggest a possible relationship between low plant sulfur status and the induction of a latent carlavirus in garlic.  相似文献   
994.
Porcine alpha (1,2) fucosyltransferase (FUT2) gene was importance in glycosphingolipid biosynthesis-globo series, potentially played a regulatory role during Escherichia coli (E. coli) F18 infection process in weaned piglets. In order to explore sequence structure of porcine FUT2 gene and its biological function, this test amplified FUT2 gene CDS sequence of Dongchuan pigs by PCR, forecasted and analyzed the protein sequences and functional regions of FUT2 gene, its expression level was detected in 11 tissues of 8 Dongchuan weaned piglets in 35 days old at the meantime. The results showed that the CDS sequence of FUT2 gene was 1 023 bp, which encoded 340 amino acids. FUT2 protein was fat-soluble hydrophilic protein, which the structure was not stable, including a transmembrane helix structure, but without signal peptide that suggested the FUT2 protein was a membrane protein;FUT2 protein included 2 N-glycosylation sites (No. 185 and No. 305 amino acids), without O-glycosylation sites, there were 14 potential phosphorylation sites, included 6 Ser, 2 Thr and 6 Tyr, analyzing the functional regions found that the FUT2 protein had a superfamily of conserved domains:FUT1-FUT2-like (58-319 amino acids). The phylogenetic tree result showed that the relative relationship between swine and cattle was relatively close, but was distant from chimpanzee, human, mouse and rat. FUT2 gene was expressed in all 11 tissues of Dongchuan weaned piglets, there were higher expression in digestive tract and immune tissues. The present results suggested that FUT2 gene might play a role to resistance to E. coli F18 in weaned piglets, and might indirectly against E. coli F18 through the synthesis of fucosyltransferase.  相似文献   
995.
Climate change bears the risk of more frequent drought stress in the northern hemisphere with more frequent early summer drought events affecting main grain crops. Winter wheat (Triticum aestivum L.) is susceptible for such drought events at the flowering and grain filling stages. After drought, the grain yield decrease of three hybrids was about 20% lower compared to three wheat lines analyzed. Wheat grain proteins are classified into four main components such as albumin and globulin, gliadin, and glutenin. The latter two are closely related to the baking quality of flour and might be affected by drought. However, detailed knowledge about the influence of drought on the synthesis of specific storage protein fractions is scarce. By analyzing the grain protein fractions by means of SDS‐PAGE technique, we detected an increase in grain protein content as well as in HMW and some LMW glutenin sub‐fractions. The glutenin fraction seems to be most variable in gene expression under different environmental scenarios such as drought. However, the protein yield as well as the grain yield may be strongly decreased, which might be not acceptable in practice.  相似文献   
996.
AIM: To investigate the molecular mechanism that hepatitis B virus X protein (HBx) inhibits the promoter activity of secreted frizzled-related protein 5 (SFRP5). METHODS: Serial truncated fragments of SFRP5 promoter were amplified and cloned into luciferase reporter vector pGL3-Basic. LO2 cells were transfected with recombinants, and then infected with the adenoviral vector expressing HBx protein (Ad-HBx) or the analogous adenovirus expressing green fluorescent protein (Ad-GFP) for control. The infection efficiency was examined under a fluorescence microscope and the activity of SFRP5 promoter was measured by luciferase assay. RESULTS: Truncated fragments of SFRP5 promoter were successfully constructed. Compared with the pGL3-Basic control, the luciferase activity was 6.32±0.04 of the -478 bp~+47 bp fragment, 5.79±0.32 of the -811 bp~+47 bp fragment, 3.59±0.34 of the -1 235 bp~+47 bp fragment, 3.86±0.39 of the -1 677 bp~+47 bp fragment and 3.26±0.42 of the -2 072 bp~+47 bp fragment, respectively. Overexpression of HBx inhibited the activity of SFRP5 promoter. The average inhibitory rates were 44% for -478 bp~+47b, 46% for -811 bp~+47 bp, 28% for -1 235 bp~+47 bp, 24% for -1 677 bp~+47 bp and 40% for -2 072 bp~+47 bp, respectively. CONCLUSION: HBx suppresses the activity of SFRP5 promoter, leading to down-regulation of SFRP5 expression.  相似文献   
997.
选用80±3日龄、体重为22.7±1.1kg的松辽黑仔猪27头,随机分为3个处理,每个处理3个重复,每个重复3头仔猪。通过测量日增重、日采食量、料肉比、腹泻程度及日粮蛋白质消化率,分析日粮蛋白质水平对松辽黑仔猪生长性能的影响。实验表明,在日采食量方面3组日粮无显著差异。日增重方面,1周和2周时对照组与实验组有差异,在整个实验期3组日粮无显著差异。料肉比方面,1周时对照组与实验组有差异,在整个实验期3组饲料的料肉比无显著差异。腹泻方面,17.7%组和14.7%组的腹泻情况优于对照组。蛋白质消化率方面,1d、2周、3周时对照组与实验组有差异,在整个实验期3组日粮差异不显著。实验表明,当日粮蛋白含量为17.7%时松辽黑仔猪有较低的腹泻率和较好的生长性能及蛋白质消化率,并能较好的体现松辽黑猪的种质特性。  相似文献   
998.
水稻OsRFP1基因的原核表达与蛋白纯化   总被引:1,自引:0,他引:1  
以推导的氨基酸序列分析,水稻OsRFP1基因编码一分子量为34.24kDa锌指蛋白。将OsRFP1基因编码区cDNA序列插入到pGEX4T-3载体中构建OsRFP1-gst融合基因的表达载体,并将质粒转化宿主菌大肠杆菌BL21DE3。经IPTG诱导,融合蛋白在BL21DE3细胞中获得表达。利用亲和层析的方法对融合蛋白进行了纯化,SDS-PAGE蛋白电泳显示获得一60kDa的唯一蛋白条带,即OsRFP1-GST融合蛋白。  相似文献   
999.
Three wheat flours, hard red winter (HRW), hard white winter (HWW) and soft red winter (SRW), were fractionated by sieving into four different particle size fractions, <38, 38–53, 53–75, and >75 μm. The medium fractions, 38–53 and 53–75 μm, of the HRW and HWW wheat had higher protein contents than the finest and coarsest fractions. The finest fractions had the highest levels of damaged starch. Tortillas made from the medium fractions of HRW and HWW, especially the 53–75 μm fraction, had longer rupture distance and better foldability. The finest fraction yielded tortillas with shorter rupture distance and worse foldability. Fractionation by flour particle size slightly affected protein composition of the flour. Size exclusion-high performance liquid chromatography (SE-HPLC) analyses showed that the compositions of SRW wheat proteins were significantly different from those of HRW and HWW wheat proteins. SRW had more low molecular weight (LMW) and less high molecular weight (HMW) protein than HRW and HWW had. The <38 μm fractions of HRW and HWW had more LMW proteins than other fractions. The amount of LMW proteins of flours correlated negatively with the rupture distance and foldability of tortillas. Particle size of the flours was the major factor affecting the tortilla texture.  相似文献   
1000.
通过人粒-巨噬细胞集落刺激因子与疏氧还蛋白融合的形式,利用PTxFus表达载体,高效地表达了其可溶性融合蛋白,该融合蛋白具有较高的热稳定性。  相似文献   
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