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41.
采用生物信息学的方法,从UniGene簇Hs.632918中选择1条人磷酸甘油酸变位酶(Phosphoglycerate mu-tase,PGAM)的表达序列标签(Expressed sequence tag,EST)AY007118.1作为种子序列进行电子步移,得到一长为2 750 bp的cDNA序列.对其进行开放阅读框(Open reading frame,ORF)分析,发现该cDNA序列具有完整的ORF框架,ORF长度765 bp,共编码254个氨基酸.cDNA 5’端具有Kozak序列、TATA盒和CAAT框,3’端具有加尾信号和Poly A尾巴.对该序列进行限制性酶切位点、CpG岛、基因定位分析,结果发现了81个酶切位点,一个长度为627 bp、GC含量为55%、Y值为0.695的CpG岛,最后将该基因定位于第12号染色体的长臂上.同时对PGAM蛋白的二级结构和特殊结构进行了初步预测.结果显示,PGAM蛋白中存在α螺旋、β-折叠片和无规卷曲结构,没有跨膜结构的片段,无信号肽,蛋白定位于细胞质或细胞核. 相似文献
42.
Pang Ze Li Ming-xue Zhou Jin-tao Qiu Zhen-dong Song Ying-ji Song Yan-ru Waqar Ahmed Song Bo Liu Shan-shan 《东北农业大学学报(英文版)》2021,28(1):1-14
Studies have shown that the three subunits of β-conglycinin are the main potential allergens of soybean sensitive patients.And β-conglycinin has adverse effects on nutrition and food processing.So solation and production of lines with lower β-conglycinin content has been the focus of recent soybean breeding projects.Soybean lines with deficiency in one or all subunits of β-conglycinin have been obtained.An effective and rapid system to identify such mutations will facilitate genetic manipulation of the β-conglycinin subunit composition.Here,two segregating F_2 populations were developed from crosses between Cgy-1/cgy-1 (CC),an α′-lacking line (Δα′),and DongNong 47 (DN47),a wild-type (Wt) Chinese soybean cultivar with normal globulin components,and Cgy-2/cgy-2 (CB),an α-lacking line (Δα),and DN47.These populations were used to estimate linkage among the cgy-1 (conferring α′-null) and cgy-2 (α-null) loci and simple sequence repeat (SSR) markers.Seven SSR markers (Sat_038,Satt243,Sat_307,Sat_109,Sat_231,Sat_108 and Sat_190) were determined to co-segregate with cgy-1,and six SSR markers (Satt650,Satt671,Sat_418,Sat_170,Satt292 and Sat_324) co-segregated with cgy-2.Linkage maps being composed of seven SSR markers and cgy-1 locus,and six SSR markers and the cgy-2 locus were then constructed.It assigned that the cgy-1 gene to chromosome 10 at a position between Sat_307 and Sat_231,and the cgy-2 gene to chromosome 20 at a position between Satt650 and Satt671.These markers should enable map-based cloning of the cgy-1 and cgy-2 genes.For different subunit-deficiency types[α′-null,α-null and (α′+α)-null types],the two sets of SSR markers could also detect of polymorphism between three normal cultivars and seven related mutant lines.The identification of these markers is great significance to the molecular marker-assisted breeding of soybean β-conglycinin subunits. 相似文献
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J. Ren H. Tang X. Yan X. Huang B. Zhang H. Ji B. Yang D. Milan & L. Huang 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2009,126(1):30-36
The enterotoxigenic Escherichia coli (ETEC) F4ac is a major cause of diarrhoea in newborn and young pigs. The locus for the intestinal ETEC F4ac receptor (F4acR) has been mapped to pig chromosome (SSC) 13q41 with known homology to human chromosome (HSA) 3q21 and q29. However, the causative gene and mutation(s) remain unknown. The aim of this study was to characterize gene-derived markers on SSC13q41 for fine mapping of the F4acR locus, and construct a high-resolution pig–human comparative map to select positional candidate genes for F4acR. Pig-specific sequence-tagged site markers were developed for 20 genes that are located in a 6.8-Mb region on HSA3q21 and q29, and a total of 34 single-nucleotide polymorphisms (SNPs) were identified in 14 of 20 markers developed. Eighteen markers were mapped to SSC13q41, while the other two markers ( PLXNA1 and KLF15 ) were assigned to SSC13q32 and SSC7q13, respectively, by radiation hybrid mapping. This result showed that there was a small conserved segment on SSC7 corresponding to HSA3q21. A framework map comprising 18 markers on SSC13q41 was established, refining the synteny breakpoint on SSC13q41 to a region of 12.3 centiRay. The comparative radiation hybrid (RH) map revealed three interesting candidate genes for F4acR from the human genome, viz. MUC4 , MUC13 and MUC20 . Linkage analysis with six marker polymorphisms revealed that MUC4 had the most significant linkage with the F4acR locus. 相似文献
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46.
电子鼻技术在食品检测中的应用 总被引:11,自引:0,他引:11
随着嗅觉传感器技术的不断发展,电子鼻技术得到了广泛的研究与应用。电子鼻由气敏传感器阵列、信号处理子系统和模式识别子系统等3种功能器件组成。为此,阐述了电子鼻技术的结构组成,介绍了其在食品新鲜度检测、果蔬成熟度评价及饮料与酒类识别等轻工业中的应用现状与发展趋势,并指出了这些新技术实现过程中所需要解决的问题。 相似文献
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在电力系统中,由于开关容量及运行方式限制,通常在低压系统中多采用1段母线、1台变压器运行方式。为了避免这种运行方式在母线检修、故障时可能造成停电的缺点,因此可用断路器将单母线分段。母线经断路器分段后。对重要用户可以从不同段引出两个回路,有两个电源供电。母线分段的数目。可以根据电源数目和容量来分.段数越多,停电的范围越小,所需电气设备越多.一般以4~6段为宜。本文对此配电母线进行N级联锁推导其算法.有利于今后解决多级联锁的问题。 相似文献
49.
徐悦 《农业机械化与电气化》2014,(4):91-92
电子商务给农产品市场注入了新的活力。阐述农产品电子商务的含义,分析我国发展农产品电子商务的可行性和面临的主要问题,指出农产品电子商务的发展方向,为改进我国农产品市场交易方式、完善市场信息服务功能提供参考。 相似文献
50.
This paper describes the practical use of a global positioning system receiver (hand-held GPS) as a means of measuring and describing pasture areas invaded by weeds. The accuracy of two GPS units, a hand-held GPS with an external antenna (GPS with an antenna) and the differential global positioning system receiver (DGPS), were examined in Morioka, northern Japan. In addition, an area of weed patches and a pasture, determined using the GPS with an antenna, were compared to the measurements made with a conventional tape and a weed map was created based on the coordinate data of latitude and longitude measurements. The accuracy of the GPS with an antenna was poor (8.3 m); however, the precision of the unit was reasonable in measuring area. An area estimation error by the GPS with an antenna was 7% when practically measuring weed patches of 141 m2 and 1% in a paddock of 12 566 m2 . From these results, it appears that the GPS with an antenna might have an acceptable error in measuring areas for weed control in a pasture. A weed map produced from the coordinate data surveyed using the GPS with an antenna enables the state of weed growth and its domination in an area of pasture to be visually understood. Therefore, GPS technologies easily can be applied to quickly obtain information on weed infestation. 相似文献