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71.
72.
异三元G蛋白是真核细胞感知外界信号后将信号传递到胞内的重要分子,参与生物体广泛的信号转导。为了研究家蚕体内G蛋白的生理功能及其作用机制,运用生物信息学方法预测了家蚕G蛋白γ1亚基(Gγ1)的序列,设计引物验证预测序列后,克隆了家蚕Gγ1的序列,再通过酶切克隆至表达载体pET-41b(+)后,导入E.coliBL21宿主菌中,经异丙基β-D-硫代半乳糖苷(IPTG)诱导表达重组谷胱甘肽硫转移酶(glutathione s-transferase,GST)融合蛋白,并亲和层析纯化表达产物。家蚕Gγ1重组GST融合蛋白经SDS-PAGE电泳和Western blot分析,在分子质量约36 kD处出现特异性蛋白条带,重组蛋白经GST亲和层析柱纯化后,得到了高纯度的融合蛋白,说明已经成功克隆到家蚕Gγ1基因,并在E.coliBL21中高效表达。 相似文献
73.
Wheat yield and quality are dependent largely on nitrogen (N) availability. In this study, we performed the first metabolomic analysis of the response to high-N fertilizer during wheat grain development using non-targeted gas chromatography-mass spectrometry (GC–MS). Quality parameter analyses demonstrated that high-N fertilizer application led to a significant increase in grain protein content and improvement in starch and bread-making quality. Comparative metabolomic profiling of six grain developmental stages resulted in identification of 74 metabolites, including amino acids, carbohydrates, organic acids and lipids/alcohol, which are primarily involved in carbon and N metabolism. Under high-N fertilizer treatment, numerous metabolites accumulated significantly during grain development. Principal component analysis revealed two principal components as being responsible for the variances resulting from N-fertilizer treatments. Metabolite–metabolite correlation analysis demonstrated that the high-N treatment group had a greater number of positive correlations among metabolites, suggesting that high-N fertilizer treatment induced a concerted metabolic change that resulted in improved grain development. Particularly, the high-N treatment-mediated significant accumulation of metabolites involved in the TCA cycle, starch and storage protein synthesis could be responsible for the improvement of grain yield and quality. Our results provide new insight into the molecular mechanisms of wheat grain development and yield and quality. 相似文献
74.
Allelic variation in high-molecular-weight glutenin subunit Loci of Glu-1 in Japanese common wheats 总被引:2,自引:0,他引:2
Seed storage proteins of 131 Japanese Norin wheat (Triticum aestivum) varieties were fractionated by sodium dodecyl sulfate
polyacrylamide gel electrophoresis to determine allelic make-up in varieties at each of three loci that control high-molecular-weight
(HMW) glutenin subunits. Three alleles were identified at the Glu-A1 locus, six at the Glu-B1 locus and five at the Glu-D1
locus. Twenty-four different, major glutenin HMW subunits were identified and each contained three to five subunits and seventeen
different glutenin subunit patterns were observed for 19 subunits in the 131 Japanese Norin varieties. Fourteen alleles were
identified by comparison of subunit mobility with that previously found in hexaploid wheat. Japanese Norin varieties showed
a specific pattern of allelic variation in glutenin HMW subunits, different from that of Chinese and other country common
wheats in allelic frequency at Glu-1 loci.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
75.
小麦编码高分子量谷蛋白亚基基因的转化 总被引:17,自引:0,他引:17
以小麦的幼穗和幼胚作为转化受体,首次用抗除草剂草甘麟的EPSPs基因作为选择标记,通过基因枪法共转化,将小麦编码高分子量谷蛋白亚基的基因1Dx5和1Dy10转移到普通小麦京花1号中,获得33株再生植株,经PCR初步检测有12株同时扩增到了3个处在不同质粒上的外源基因EPSPs, 1Dx5和1Dy10的目标片段。将部分PCR检测为阳性的转化体 相似文献
76.
Due to their broad population diversity, old wheat varieties or landraces play an important role in increasing the genetic
variability of agronomic traits. On these grounds, an analysis was made of the high molecular weight (HMW) glutenin subunit
composition of the old Hungarian wheat variety Bánkúti 1201. It was found that several genotypes with differing breadmaking
qualities can be distinguished for this character. When using old varieties in breeding, it is possible to broaden the genetic
background of characters responsible for breadmaking quality by separating the populations. A more detailed analysis of the
protein composition of germplasm created in this way will be required to obtain a better understanding of this complex character
for its conscious introduction into breeding programmes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
77.
普通小麦胚乳谷蛋白亚基的遗传研究 高分子量谷蛋白亚基变异的多样性及其在F#-1的遗传行为 总被引:23,自引:2,他引:21
本文研究了70个普通小麦品种和4个烘烤品质优良的亲本与4个农艺亲本间配置的20个正反交F#-1,以及1个杂交小麦F#-1的胚乳高分子量谷蛋白亚基。发现它们在品种间的变异较大,在品种内是稳定和一致的。它们在杂种F#-1呈现共显性遗传和倾母现象。讨论了杂种F#-1胚乳高分子量谷蛋白亚基共显性遗传在杂种判断和品种纯度鉴定中的应用。 相似文献
78.
First record of the little fire ant,Wasmannia auropunctata (Hymenoptera: Formicidae), in Chinese mainland
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In January 2022, we received ant specimens collected from three field colonies from Shantou City, Guangdong Province, China. They were identified as the little fire ant, Wasmannia auropunctata, through morphological and molecular analyses. Wasmannia auropunctata is listed as one of the 100 most dangerous invasive species by the International Union for Conservation of Nature (IUCN) and has spread from its native range in South America to every continent except Antarctica. DNA analysis of mitochondrial cytochrome c oxidase subunit I (COI) in nine specimens of W. auropunctata found that they had a close genetic relationship with specimens from Argentina. This study represents the first formal record of the establishment of W. auropunctata outdoor in Chinese mainland. However, the invasion stage and occurrence degree of W. auropunctata in China are not clear to date. The implementation of quarantine measures, investigation of the occurrence and distribution, and development of monitoring and control strategies are needed to actively respond to the threat posed by this highly invasive ant. 相似文献
79.
大肠杆菌肠毒素ST1—LTB融合蛋白工程菌株的免疫原性研究 总被引:9,自引:1,他引:8
已构建的能表达大肠杆菌肠毒素ST1LTB融合蛋白的工程菌株BL21(DE3)(pXETSLT1)及其表达产物经动物试验证实没有毒性反应。用从IPTG诱导的工程菌中提取的包涵体或经甲醛灭活的工程菌制成抗原,免疫小鼠,结果免疫小鼠至少能抵抗15MLD的大肠杆菌强毒株C83902(K88ac,ST+,LT+)的攻击。用提取的包涵体免疫家兔后,采集的血清能够中和天然ST1的毒性。这表明构建的工程菌株BL21(DE3)(pXETSLT1)可以作为预防幼畜大肠杆菌性腹泻基因工程菌苗的候选株。 相似文献
80.
为了证实长发带芒草中的y型高分子量谷蛋白亚基的存在,利用SDS-PAGE分析了3份长发带芒草的高分子量谷蛋白亚基组成,发现其y亚基的迁移率均较普通小麦中迁移率最快的D y12亚基迁移率更快,应用PCR扩增、序列测定及基因编码区体外表达等方法研究了1份材料中的y亚基,确认了长发带芒草比普通小麦中迁移率最快的D y12亚基迁移率更快的T ay亚基的真实存在及表达。研究结果证实带芒草属具有与普通小麦中相类似的y型高分子量谷蛋白亚基。 相似文献