Genomic and genic sequence variation in synthetic hexaploid wheat （AABBDD） as compared to their parental species

In order to understand the genomic changes during the evolution of hexaploid wheat, two sets of synthetic hexaploid wheat from hybridization between maternal tetraploid wheat （AABB） and paternal diploid goat grass （DD） were used for DNA-AFLP and single strand conformation polymorphism （SSCP） analysis to determine the genomic and genic variation in the synthetic hexaploid wheat. Results indicated that more DNA sequences from paternal diploid species were eliminated in the synthetic hexaploid wheat than from maternal tetraploid wheat, suggesting that genome from parental species of lower ploidity tends to be eliminated preferentially. However, sequence variation detected by SSCP procedure was much lower than those detected by DNA-AFLP, which indicated that much less variation in the genic regions occurred in the synthetic hexaploid wheat, and sequence variations detected by DNA-AFLP could be derived mostly from non-coding regions and repetitive sequences. Our results also indicated that sequence variation in 4 genes can be detected in hybrid F1, which suggested that this type of sequence variation could be resulted from distant hybridization. It was interesting to note that 3 out of the 4 genes were mapped and clustered on the long arm of chromosome 2D, which indicated that variation in genic sequences in synthetic hexaploid wheat might not be a randomized process.     

Differential binding of conA and WGA on the cell surface,the role of sialic acid in their expression and the increased activity of sialidase after cis-Platin treatment

Summary It is reported that concanavalin A (conA) and wheat germ agglutinin (WGA) have a differential binding pattern on normal mouse spleen lymphocytes and the surface of Dalton's lymphoma cells. It is suggested that sialic acid on the cell surface controls the expression of lectin binding sites. Further, it has been observed that the increased release of sialic acid from cell surfaces aftercis-dichlorodiammine platinum (II) (cis-Platin) treatment is due to the increased activity of sialidase.To whom reprint requests should be addressed.     

反胶束中脂肪酶CSL催化性能的研究

以葵花籽油为底物，考察了未见报道的国产脂肪酶ＣＳＬ在ＡＯＴ／异辛烷反胶束体系中的催化性能，当底物体积分数为１０％，ＰＨ＝８．０，Ｔ＝３１３Ｋ，水与表活性剂的浓度比Ｗ０＝１２时，脂肪酶的催化活力最高；而且，当底物体积分数为２０％时，仍未发生抑制现象。     

四川栽培小麦幼胚培养再分化能力变异性的研究

以N6为基本培养基，对四川栽培小麦品种、品系以及农家品种共45个基因型的幼胚离体培养，进行了植株再生能力变异性的研究。结果表明，供试材料间的形态发生能力存在明显变异，表现为器官建成速度明显不同，芽器官和根器官再生率存在极显著差异，分别变异在15．00％－95．45％和0－95．45％之间，由每个幼胚外植体起源的愈伤组织再生出1．0cm以上的芽数及其芽长均存在极显著差异。     

Contents and distribution of rare earth elements in wheat seeds

Contents of 15 rare earth elements (REEs) in the seeds of 60 breeds of wheat have been analyzed by the inductively-coupled plasma mass spectrometry (ICP-MS). The distribution pattern of contents of REEs in wheat seeds has been observed and compared with that in soils. Comparison with literature data has also been made. The results show that the background of REEs in wheat seeds is 10-11-10-8 g.g-1, 3-4 levels lower than in soils. The distribution pattern is light REEs higher in contents and slight Eu-anomaly, similar to that in soils. The data obtained in this study can accurately represent the background content of REEs in wheat seeds.     

脂肪酶基因结构和氨基酸序列的比较

采用PCGENE6 8软件系统对真菌脂肪酶基因和氨基酸序列进行了分析。真核生物中多数结构基因中含有内含子 ,但真菌脂肪酶基因几乎有一大半的是连续的 ;对于有内含子的基因 ,不同脂肪酶基因所含内含子数目各异。所有脂肪酶一级结构中都包含Gly X1 Ser X2 Gly保守序列 ,在真菌脂肪酶中该序列更保守 ;Ser、Asp/Glu和His3个氨基酸残基组成了真菌脂肪酶的活性中心 ;大多数真菌脂肪酶是糖蛋白 ,但也有一些不含糖基的脂肪酶 ,主要取决于脂肪酶一级结构中是否存在糖基化识别序列。     

抗大鼠肝脏脂酶抗血清的制备及应用

按照ＲＨＬｃＤＮＡ核苷酸序列所预示肽链的氨基酸序列，化学合成了与肽链Ｎ端、Ｃｕｍｄｊｔ ｋ ｕｋ ｓｈ ｃｆ ｙｉｄ ｒ ３ｗｈ ｅｅｄｙ     

利用多因素综合相关法预测小麦赤霉病发生程度的数学模型及其应用

小麦赤霉病是一种气候流行病,其发生流行程度的轻重,主要取决于当地4月下旬到5上旬小麦抽穗开花期20天内的气候条件,如果气温适合、湿度大时,则蔓廷成灾。本文是采用多因子综合相关法,通过计算条件频率得出预报方程,其历史拟合率高达95.6％。