Sequence analysis of mRNA polyadenylation signals of rice genes

Most eukaryotic mRNAs receive a poly (A) tail at their 3′-ends through a process involving the cleavage of pre-mRNA and the concomitant polymerization of adenosine residues to the cleaved RNA end[1,2]. As un- translated regions (UTRs) may contain importa…     

Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution

We present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome--composed of approximately one billion base pairs of sequence and an estimated 20,000-23,000 genes--provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture.     

The ovalbumin gene region: common features in the organisation of three genes expressed in chicken oviduct under hormonal control.

Two large DNA fragments overlapping the chicken ovalbumin gene have been isolated by molecular cloning. Analysis of these fragments provided a map of a 46,000-base pair region of the chicken genome. This region contains the complete ovalbumin gene (including its mRNA leader-coding sequence) and at least two other genes of unknown function. All three genes are orientated in the same direction and their expression in chicken oviduct is under hormonal control. The three genes share some sequence homologies, suggesting that duplications have occurred in the ovalbumin gene region in the course of evolution.     

Q-Sepharose FF色谱分离制备鸡蛋卵白蛋白的研究

目的研究鸡蛋卵白蛋白的分离工艺条件。方法采用Q-Sepharose FF色谱法分离鸡蛋清中的卵白蛋白,并用电泳和RP-HPLC色谱法测定其纯度。结果在40mL色谱柱（Ф2．0cm×20cm）中,蛋清（蛋白质含量为27．5mg／mL）进样量为140mL时,色谱柱对卵白蛋白的吸附量达到饱和;用含0．15mol／L NaCl的Tris-HCl（pH8．0）洗脱液洗脱,获得的鸡蛋卵白蛋白的纯度达92％。结论采用Q-Sepharose FF色谱法分离鸡蛋卵白蛋白,整个工艺路线简便、快捷、成本低、效率高,适宜于工业生产应用。     

Chicken ovalbumin contains an internal signal sequence.

Ovalbumin is shown to contain an internal rather than an amino-terminal signal sequence. This internal signal can be recovered in a tryptic fragment which comprises residues 229--276 of mature ovalbumin and contains a region of striking sequence homology to amino-terminal cleaved signals of two other oviduct secretory proteins. The isolated tryptic fragment is used as a probe to demonstrate that a signal receptor is present in membrane vesicles derived from the rough but not in those derived from the smooth endoplasmic reticulum.     

Lucas数列的模数列的周期性

针对Lucas数列{Ln}以及给定的正整数m,由Ln关于模m的最小非负剩余bn构成一个新的数列{bn},称为Lucas数列的模数列.利用初等数论的相关知识和数学归纳法,证明了Lucas数列的模数列是周期数列,并且是纯周期数列.     

Isolation by molecular cloning of a fragment in the split ovalbumin gene

An EcoRI fragment of chicken DNA (fragment 'a') containing a sequence complementary to the 3' half of ovalbumin mRNA has been isolated by molecular cloning. Analysis of the cloned fragment proves conclusively that the chicken ovalbumin gene is split. Fragment 'a' contains no extensive sequence repeated elsewhere in the genome and represents the only type of organisation of this part of the split ovalbumin gene in chicken genome.     

有限自动机积的初(末)态试验序列、UIO序列和同步序列

主要对积运算后有限自动机的初(末)态试验序列、U IO序列和同步序列进行了讨论,给出了积运算后的有限自动机与积运算前有限自动机的初(末)态试验序列、U IO序列和同步序列的联系,并给出了极小有限自动机的初态试验序列与U IO序列间的联系。     

正定矩阵序列与其多项式序列

本文得出了正定矩阵序列收敛的等价定理,并给出其P-型和Q-型矩阵多项式序列的性质。     

DNA序列的分类

本文由浅入深提出三种分类模型,应用统计知识进行检验并指导分类,得到了精度较高的模型2和模型3,对从数学的角度解读人类基因图谱提供了一种思路。