基因词汇二
A
alternative splicing -- Eukaryotic genes are composed of exons and introns, the latter being removed by RNA splicing before transcribed mRNA leaves the nucleus. Commonly, a single gene can encode several different mRNA transcripts, caused by cell- or tissue-specific combination of different exons. This is known as alternative splicing.
Annealing -- The time- and temperature-dependent process by which two complementary single-stranded polynucleotides associate to form a double helix (see also hybridization)
Antisense strand -- the DNA strand of a gene which, during transcription, is used as a template by RNA polymerase to synthesize a complementary RNA strand.
反股 -- 意指一股DN**段为基因之所在,因此可用来当做模版使得RNA反转录脢在转录RNA时,可以合成和此DN**段完全结合的RN**段。
B
Bifurcation -- The graphical representation in a phylogenetic tree of an evolutionary speciation event whereby an ancestral taxon splits into two.
分歧点 -- 在演化的种形成事件中,物种由相同来源一分为二,其在种系发生树中的图示点。
blotting -- General term for the transfer of protein, RNA or DNA molecules from a relatively thick acrylamide or agarose gel to a paper-like membrane (usually nylon or nitrocellulose) by capillarity or an electric field, preserving the spatial arrangment. Once on the membrane, the molecules are immobilized, typically by baking or by ultraviolet irradiation, and can then be detected at high sensitivity by hybridization (in the case of DNA and RNA), or antibody labelling (in the case of protein). RNA blots are called Northern blots; DNA blots, Southern; protein blots, Western.
Blunt ends -- Descriptive of the structure of double-stranded DNA in which neither strand of the duplex extends further from the end than the other; often the product of cleavage by a restriction endonuclease. (see also sticky ended)
Branch -- The graphical representation of an evolutionary relationship in a phylogenetic tree.
分枝 -- 在种系发生树中,物种演化相互关系的图示。
C
Cancer Genome Anatomy Project -- The Cancer Genome Anatomy Project (CGAP) is an interdisciplinary program established and administered by the National Cancer Institute (NCI) to generate the information and technological tools needed to decipher the molecular anatomy of the cancer cell.
癌症基因体解剖计划 -- 癌症基因体解剖计划(CGAP)已经由国际癌症学会(NCI)建立并经营于于各个学科间,主要是产生信息及技术工具以便解决癌症细胞的分子解剖的各项秘密
Cap -- a specialized chemical group that is naturally added to the 5’ end of mRNA.
帽子 -- 一个特殊群,在自然下会加到5端的mRNA上
CASP -- Critical Assessment of techniques for protein Structure Prediction
CASP -- 于蛋白质结构的预测上作一关键性的技术评估
cDNA -- Complementary DNA; DNA that is synthesized, by reverse transcriptase, from an mRNA template, and therefore has no introns. (see also genomic DNA)
cDNA library -- A collection of cells, usually E. coli, transformed by DNA vectors each of which contains a different cDNA insert synthesized from a collection of mRNA species. (see also genomic library)
Cis-element -- a regulatory DNA sequence that serves as a protein binding site and controls the transcription of adjacent genes.
Clade -- A complete group of organisms derived from a common ancestor.
进化枝,分化枝 -- 生物体的全部族群源自于共同始祖
Cloning vector -- A technique for obtaining the desired gene that involves "chopping up" the entire genetic complement of a cell using restriction enzymes, then attaching each (resultant) DNA fragment to a vector and transferring it into a bacterium, and finally screening those (engineered) bacteria to locate the bacteria that are producing the desired product (e.g., a protein).
Codon -- a nucleotide triplet which specifies an amino acid or a signal for terminating the synthesis of a polypeptide.
密码子 -- 对应到特定胺基酸的核甘酸三联体或使多月太链合成中止的讯号
Consensus tree -- A branching diagram produced using a method for combining the grouping information contained in a set of cladograms for the same taxa into a single topology.
共同树 -- 利用分枝图分群方式合并分群讯息, 使相同之taxa包含在进化枝的集合中
Convergence -- The independent evolution of similar genetic or phenotypic traits.
收敛 -- 具相似基因或表现型特征的独立演化
CpG islands -- short stretch of DNA, often <1 kb, containing CpG dinucleotides which are unmethylated and present at the expected frequency. CpG islands often occur at transcriptionally active DNA.
CpG island -- 长度小于 1000 个碱基的脱氧核糖核酸 , 其中包含未甲基化的CpG 双核甘酸序列 , 并以特定的频率出现 . CpG island 通常出现在随时准备好转录或转译的脱氧核糖核酸中可以观察到
D
dbEST -- dbEST is a division of GenBank that contains sequence data and other information on "single-pass" cDNA sequences, or Expressed Sequence Tags, from a number of organisms.
表现序列标帜数据库 -- 表现序列标帜数据库是基因库内的一部份,内含序列数据库和”只有单股定序”的互补DNA(cDNA)序列信息或一些生物体的表现序列标帜
Denaturation -- The destruction of the ordered folding of a protein or nucleic acid that is required for its normal function. Protein denaturation often involves a change from a specific globular or fibrous conformation to a random coil; nucleic acid denaturation often involves the dissociation of a duplex into single strands. (see also native structure)
Digital Differential Display -- Survey sequencing of mRNA gene products provides an indirect means of generating gene expression fingerprints for cancer cells and their normal counterparts. Digital Differential Display (DDD) is a computer method for comparing these fingerprints. Using a statistical test, genes whose expression levels differ significantly from one tissue to the next are identified and shown to the user.
数字差异陈列 -- 观察mRNA基因的序列产生提供一间接方法为了癌症细胞及与癌症细胞极为相似但是正常的细胞能够产生基因表现指纹。数字差异陈列(DDD)是利用计算机统计的方法来比较各个组织不同层级的基因表现。
Distance (evolutionary distance) -- A measure of the number of nucleotide substitutions per nucleotide site between two homologous DNA sequences that have accumulated since the divergence between the sequences.
距离(演化远近)-- 从两条相似DNA序列间发生相异处收集每个核甘酸位置发生替换个数的量度
Divergence -- The splitting of a taxonomic unit into two.
DNA cloning -- The production of a lineage of cells all of which contain one kind of DNA fragment of interest derived from a population of many kinds of DNA fragments. Operationally by:
inserting (recombining) a population of DNA molecules, known to contain the DNA of interest, into a population of vector DNA molecules in such a way that each vector molecule contains only a single DNA molecule from the original population;
transforming a population of host cells with the vector DNA recombinants such that each host cell takes up only one vector;
growing single host cells separately (cloning) by plating at low density to form a collection of separate colonies;
screening the colonies (clones) formed for the presence of the DNA of interest.
DNA library -- A library composed of complementary copies of cellular messenger RNAs.
DNA microarray -- Initially developed by Patrick Brown during the 1980s, these microarrays enable analysis of the levels of expression of genes in an organism, or comparison of gene expression levels (e.g., between diseased and non-diseased tissues) via hybridization of messenger RNA (mRNA) to its counterpart DNA sequence... when biological samples containing DNA (e.g., in liquid) are passed-over the array surface.
DNA polymerase -- An enzyme that can synthesize new DNA strands using a DNA template; several such enzymes exist. One of several classes of enzymes that polymerize DNA nucleotides using single or double-stranded DNA as a template.
dot blot -- Method for detecting a specific protein or message. A spot of solution is dotted onto nitrocellulose paper, a specific antibody or probe is allowed to bind and the presence of bound antibody/probe then shown by using a peroxidase-coupled second antibody, as in Western blot or by other visualization methods.
点印 -- 侦测特殊蛋白质或遗传讯息的方法. 在硝化纤维纸上点上特殊的点状溶液, 其中含有特殊的抗体或探针,在这些抗体或探针上再使用过氧化反应连结上二次抗体,用以提供呈色反应, 就类似西方转渍反应或者其它类似的方法.
E
Ectopic (illegitimate) transcription -- low-level transcription in many cell types of genes which are predominantly expressed in certain types of cell
易位(不合规则)转录 -- 在许多形式细胞低量转录某些特定细胞显著表现的基因
exon -- The sequences of the RNA primary transcript (or the DNA that encodes them) that exit the nucleus as part of a messenger RNA molecule. In the primary transcript neighbouring exons are separated by introns.
表现子 -- 离开原子核成为讯息核糖核酸分子的核糖核酸主要转录序列。 在主要转录过程附近,表现子会被介入子所分开。
F
G
gene -- Originally defined as the physical unit of heredity but the meaning has changed with increasing knowledge. It is probably best defined as the unit of inheritance that occupies a specific locus on a chromosome, the existence of which can be confirmed by the occurrence of different allelic forms. Given the occurrence of split genes, it might be re-defined as the set of DNA sequences (exons) that are required to produce a single polypeptide.
基因 -- 原本是定义遗传上的物质单位,但随着知识的增加意义也随之改变。也许现在最好定义它是遗传上的单位,占有染色体上一个特别的区域,可被证实有不同的对偶型式。对分离的基因来说,它可被定义成一组需要用来产生蛋白质的脱氧核糖核酸序列,即外子。
genomic DNA -- DNA that has been isolated from a cell and therefore contains introns, as opposed to cDNA
Genomic library -- A collection of transformed cells, each of which contains DNA fragments; the entire population represents the total genome of an organism, e.g. a rat library containing DNA fragments which together comprise the entire rat genome. Appropriate screening methods can select a single transformed cell that contains a specific gene. (see also cDNA library)
Glycosylation -- the addition of carbohydrates to proteins.
醣化作用 -- 在蛋白质上连接碳水化合物。
H
Helicase -- A protein that unwinds DNA at replication forks.]
HGI -- HGI, the Human Gene Index, replaced the Human cDNA Database(HCD) in April of 1997. HGI contains human EST sequences sequenced at TIGR as well as human ESTs from GenBank's dbEST database. There are a set of 29 non-human gene indices at TIGR. All the information contained in these databases is free, no password or contract is required as it was with HCD. In addition to the Indices, TIGR offers the TIGR Microbial Database, the TIGR Parasites Database, the Expressed Gene Anatomy Database, and the BAC End Sequence Database.
HGI -- 全名为Human Gene Index。是人类基因的参考索引,在1997年4月时候取代了HCD(Human cDNA Database)的功能。HGI包含NCBI(GeneBank)中db EST数据库及TIGER机构所定序出来的人类表现序列标志(EST)序列信息。此外,在TIGER机构中也有29个非人类的基因参考索引(non-human gene indices),而且所有信息都是免费的;像HCD一般,不需签合约与通关密码就可取得信息。除了基因的参考索引,TIGER机构也提供微生物数据库(TIGER Microbial Database)、寄生虫数据库(TIGER Parasites Databases)、表现基因之解剖学数据库(Expressed Gene Anatomy Database)以及BAC载体端序列数据库(BAC End Sequence Database)。
Housekeeping genes -- Tissue-specific gene expression
持家基因 -- 属于特定组织才有的基因表现
Hybridization -- (of nucleic acids) Technique in which single-stranded nucleic acids are allowed to interact so that complexes, or hybrids, are formed by molecules with sufficiently similar, complementary sequences. By this means the degree of sequence identity can be assessed and specific sequences detected. The hybridization can be carried out in solution or with one component immobilized on a gel or, most commonly, nitrocellulose paper. Hybrids are detected by various means: visualization in the electron microscope; by radioactively labelling one component and removing non-complexed DNA; or by washing or digestion with an enzyme that attacks single-stranded nucleic acids and finally estimating the radioactivity bound. Hybridizations are done in all combinations: DNA-DNA (DNA can be rendered single-stranded by heat denaturation), DNA-RNA or RNA-RNA. In situ hybridizations involve hybridizing a labelled nucleic acid (often labelled with a fluorescent dye) to suitably prepared cells or histological sections. This is used particularly to look for specific transcription or localization of genes to specific chromosomes (FISH analysis).The time- and temperature-dependent process by which two complementary single-stranded polynucleotides associate to form a double helix = annealing (hybridization)
Homology -- Similarity by common ancestry or genetic relatedness.
I
I.M.A.G.E. Consortium Goals -- The I.M.A.G.E. Consortium was initiated in 1993 by four academic groups on a collaborative basis after informal discussions led to a common vision of how to achieve an important goal in the study of the human genome: the Integrated Molecular Analysis of Genomes and their Expression. Specifically, we share high-quality, arrayed cDNA libraries and place sequence, map, and expression data on the clones in these arrays into the public domain. Using this information, unique clones can be rearrayed to form a "master array" which we hope will ultimately contain a representative cDNA from each and every gene in the genome under study. The human and mouse genomes are the first to be studied. Recently, rat, zebrafish, and Xenopus have been added, and we anticipate arraying (and sharing) cDNA libraries from additional species over time. All of our clones are available free of any royalties, and may be used by anyone agreeing with our guidelines.
I.M.A.G.E. 联盟目标 -- 公元1993 年四个学术团队在非正式讨论后,对于如何达成人类基因体研究重要目标有了共识,因此开始合作I.M.A.G.E. 联盟:基因体及其表现的整合性分子层次分析。尤其我们将高品质排列好的互补脱氧核糖核酸( cDNA ) 数据库以及这些微盘数组中植株的序列图谱和表现资料置于公众领域。利用这个信息,我们希望将来可以产生包含研究中基因体每一个基因的各个代表性互补脱氧核糖核酸的最终「原版微盘数组」, 并从其中重新排列出独一无二的植株组。最先研究的是人类和小鼠的基因体。近来大鼠,斑马鱼和非洲有爪水生蛙( Xenopus )的研究陆续加入,我们预期排列(和共享)新加入研究物种的互补脱氧核糖核酸数据库也会陆续产生。我们所有的植株免任何授权费提供任何人在同意我们规范指导下的使用。
Informative site -- A site that is used to choose the most-parsimonious tree from among all the possible phylogenetic trees. In molecular evolution, a site where there are at least two different kinds of nucleotides or amino acids, and each of them is represented in at least two sequences.
intron -- A non-coding sequence of DNA within a gene (cf. exon), that is transcribed into hnRNA but is then removed by RNA splicing in the nucleus, leaving a mature mRNA that is then translated in the cytoplasm. Introns are poorly conserved and of variable length, but the regions at the ends are self-complementary, allowing a hairpin structure to form naturally in the hnRNA; this is the cue for removal by RNA splicing. Introns are thought to play an important role in allowing rapid evolution of proteins by exon shuffling. Genes may contain as many as 80 introns.
介入子 -- 基因内未编码的DNA序列(参见编码顺序), 虽然它转录成hnRNA, 但在细胞核内RNA剪接后移除, 保留成熟的mRNA, 亦即在细胞质内进行转译. Intron 不易保存且长度多变, 但在末端区域它能自我互补, 并且在hnRNA内行成自然型式的发簪结构, 这暗示着RNA剪接后移除. Intron 在蛋白质编码顺序曳步的快速发展扮演重要角色, 基因中可能含有80个以上的 intron.
J
K
L
Lagging strand (Okazaki fragment) -- Fragments of a single-stranded DNA synthesized on the discontinuous site of a DNA replication fork. (see also semi-discontinuous)
Leading strand -- The continuous DNA strand synthesized at a fork during DNA replication. (see also lagging strand; semi-discontinuous)
Ligase -- One of a class of enzymes that join two substrate molecules in energy- (usually ATP-) dependent reaction, e.g. an amino acyl-tRNA synthetase, a carboxylase; in molecular biology, an enzyme that attaches the 3'-end of one polynucleotide to the 5'-end of another. (see also synthetase)
Locus control region (LCR) -- a stretch of DNA containing regulatory elements which control the expression of genes in a gene cluster that may be located tens of kilobases away.
基因点控制区 -- 一群基因丛集中额外含有控制基因表现的调节子的DNA,可能位于数万个碱基之外
M
Maximum parsimony -- The selection of the phylogenetic tree requiring the least number of substitutions from among all possible phylogenetic trees as the most likely to be the true tree.
Messenger RNA (mRNA) -- an RNA molecule that serves as a template for protein synthesis.
信使核糖核酸 -- 核糖核酸的一种,当蛋白质合成中当作模板指定讯息的转译。
Monophyletic -- Sharing a common ancestor.
Multifurcation -- A graphical representation of an unknown branching order in a phylogenetic tree involving three or more taxa. Rarely, a graphical representation of a speciation event resulting in the simultaneous production of more than two species.
N
Natural selection (selection) -- Differential reproduction of different members of a species due to the variability in fitness among individuals or genotypes, leading to changes in allele frequencies over time.
天择 -- 天择是改变对偶基因频率的主要因素,因为天择的结果使某种基因型的个体减少,因而改变原有的对偶基因频率。
Neutral mutation -- Evolution at the molecular level is primarily determined by mutational input and random genetic drift, rather than by natural selection.
天然突变 -- 演化过程中在分子的层次上主要是经由随机的基因流而决定,并非藉由天择所影响。
Northern blot -- An electroblotting method in which RNA is transferred to a filter and detected by hybridization to32 P-labelled RNA or DNA.
北方转渍法 -- 一种电子转印方法,将 RNA 转移至滤纸上,加上要试验的放射性标志RNA或DNA,以进行杂合,以自动显影技术观察
O
P
PDB -- Protein Data Bank
PDB -- 蛋白质数据库
Phylogenetics -- The reconstruction of the evolutionary history of a group of taxa or genes.
中性(一般)突变 -- 分子层次的演化,主要来自天然突变和遗传漂变,而不是天择。
系统发生学重建生物之间数个相关种或一群相关基因的演化历史
Phylogeny -- The evolutionary history of a group of taxa or genes and their ancestors.
Poly-A tail -- a tract of about 200 adenine nucleotides added to the 3’ ends of eukaryotic mRNAs.
Polyadenylation -- the process of adding a poly-A tail to a pre-mRNA.
Polymerase chain reaction (PCR) -- The first practical system for in vitro amplification of DNA, and as such one of the most important recent developments in molecular biology. Two synthetic oligonucleotide primers, which are complementary to two regions of the target DNA (one for each strand) to be amplified, are added to the target DNA (that need not be pure), in the presence of excess deoxynucleotides and Taq polymerase> Taqpolymerase, a heat-stable DNA polymerase. In a series (typically 30) of temperature cycles, the target DNA is repeatedly denatured (around 90°C), annealed to the primers (typically at 50-60°C) and a daughter strand extended from the primers (72°C). As the daughter strands themselves act as templates for subsequent cycles, DNA fragments matching both primers are amplified exponentially, rather than linearly. The original DNA need thus be neither pure nor abundant, and the PCR reaction has accordingly become widely used not only in research, but in clinical diagnostics and forensic science.
聚合(酉每)反应 -- 以人工方法将一段DNA复制,是分子生物近期的一项重大发明。利用两种合成的引发物(primer),互补于目标DNA的两端(分别在不同的单股),加入目标DNA(不需特别纯化),加入过量的dNTP和Taq聚合(酉每)( Taq聚合(酉每) : 是耐热(酉每) )。在一连续的温度变化周期(典型30个周期),重复的使目标DNA变性(约摄氏90度),黏附住引发物(典型于摄氏50-60度)借此延伸复制出子股(摄氏72度)。而子股则在下一次的周期中被当成新的模板,这些DN**段以指数性倍率被复制,并非线性。如此一来取得的DNA可以容许不够干净或量极少,因此聚合(酉每)反应不只用于科学研究,也被广泛的用于临床使用和法医学上。
Pre-mRNA -- the primary transcripts that are processed to form messenger RNAs in eukaryotic cells.
信使核糖核酸前驱物 -- 为脱氧核糖核酸经由转录而得的最初转录体,要再经过修饰处理才变成信使核糖核酸,在真核生物中,修饰的作用包括5’端的加帽作用及3’端的聚腺核苷酸化作用,此外,也会进行编码序列剪接作用。
Primase -- An enzyme that creates an RNA primer for initiation of DNA replication.
Primer -- An RNA sequence hybridized to a DNA template whose elongation by a DNA polymerase constitutes DNA synthesis. A random primer is a mixture of polynucleotides with all four bases at each sequence position; an arbitrary primer is a single species with a single base at each sequence position.
Probe -- A polynucleotide, often radiolabelled, used to detect complementary sequences, e.g. an mRNA used to locate its gene by a corresponding Southern blotting method.= hybridization probe
Promoter -- a combination of short sequence elements to which RNA polymerase binds in order to initiate transcription of a gene.
R
Reading frame -- The translational reading frame describes the mechanism which moves a ribosome three nucleotides at a time during translation.
读取片段 -- 一种机制,用于描述核醣体在转译的过程,一次移动三个核甘酸
Recombinant DNA technology -- Techniques of gene cloning. Recombinant DNA refers to the molecule formed by joining a DNA of interest to vector DNA. See gene cloning.
Replication forks -- The point at which the two strands of DNA are separated to allow replication of each strand.
Restriction endonucleases -- Endonuclease that recognizes a particular short DNA sequence which they cleave. They help to protect cells from viral infection and are used in work with DNA.
Reverse transcriptase -- A DNA polymerase that uses an RNA template; an RNA-dependent DNA polymerase.
Ribosomal RNA (rRNA) -- the RNA component of ribosomes.
核糖体核糖核酸 -- 核糖核酸的一种,为组成核糖体的成分
Ribosomes -- particles composed of RNA and proteins that are the sites of protein synthesis.
粒线体 -- 由核糖核酸和蛋白质组成的颗粒,是蛋白质合成的场所.
Root -- In rooted trees, the common ancestor of all the taxa under study.
RNA (ribonucleic acid) -- a polymer of ribonucleotides
核糖核酸 -- 为核糖核苷酸的聚合物,核糖核甘酸由含氮碱基、五碳醣基与磷酸根组成,其中碱基决定为哪一种核糖核酸,核糖核苷酸的种类有四种,有:腺核糖核苷酸、尿核糖核苷酸、鸟份核糖核苷酸、胞核糖核苷酸
RNA splicing -- RNA sequences transcribed from introns are excised and discarded while those transcribed from exons are spliced together in the same linear order as the exons.
S
SAGE -- Serial Analysis of Gene Expression, or SAGE, is an experimental technique designed to gain a quantitative measure of gene expression. The SAGE technique itself includes several steps utilizing molecular biological, DNA sequencing and bioinformatics techniques. These steps have been used to produce 9 or 10 base "tags", which are then, in some manner, assigned gene descriptions. For experimental reasons, these tags are immediately adjacent to the 3' end of the 3'-most NlaIII restriction site in cDNA sequences
SAGE -- 基因表现的连续分析(SAGE),是一种实验的设计为了得到一个确切的基因表现量。SAGE技术包括利用几个分子生物的步骤,DNA定序及生物信息的技术。这个步骤可以产生9或10个碱基的”标签”经由实验的结果,这些标签会接近含有大量NlaIII限制脢的cDNA序列的3端
Sense strand -- the DNA strand of a gene which is complementary in sequence to the anitsense strand, and identical to the transcribed RNA sequence, except that in the latter the base thymine has consistently been replaced by uracil.
Signal (leaser) sequence -- a hydrophobic sequence at the amino terminus of a polypeptide chain that targets it for secretion in bacterial or incorporation into the endoplasmic reticulum in eukaryotic cells.
讯息(指挥)序列 -- 蛋白质末端的一段疏水性氨基酸,在细菌中引导蛋白质分泌或在真核细胞中将蛋白质并入内质网。
Signal recognition particle (SRP) -- a particle composed of proteins and 7SL RNA that binds to signal sequences and targets polypeptide chains to the endoplasmic reticulum.
讯号认识颗粒 -- 由蛋白质和7sL RNA所组成的颗粒,会与讯号序列结合并带领生太链到内质网中
Single-strand binding protein (SSB) -- Protein that binds to single-stranded DNA usually near the replication fork to stabilize the single strands.
SnRNA -- small nuclear RNA species, such as the U1, U2, U3 series, which are often involved in the RNA splicing mechanism.
SnRNA -- 为 small nuclrar RNA 的缩写 ,为小分子的核糖核酸 , 例如 U1 , U2 , U3 系列 , 通常与核糖核酸的剪接有关
Splice acceptor site -- the junction between the end of an intron terminating in the dinucleotide AG, and the start of the next exon.
剪接接受位 -- 位在介入子终端的AG核苷对和下一个表现子之间的接合点
Splice donor site -- the junction between the end of an exon and the start of the downstream introns, commencing with the dinucleotide GT.
剪接提供位 -- 位在表现子终端和下一个表现子之间的接合点,由GT核苷对起始.
Sticky ends -- Descriptive of the structure of a double-stranded polynucleotide in which one strand extends further from the end than the other to create a single-stranded 'tail'; especially the product of cleavage by a restriction endonuclease at a palindromic sequence. Also known as cohesive ended or staggered ended. (see also blunt ended (flush ended))
T
TATA box -- a common promoter element.
Taxon (plural, taxa) -- A taxonomic group of any rank (e.g., species, genus, etc.) to which individual organisms are assigned.
Template -- A polynucleotide that encodes the information from which another polynucleotide, of complementary sequence, is synthesized.
Topology -- The branching pattern of a phylogenetic tree.
拓朴学 -- 演化树的分枝图样
Transcription -- the synthesis of RNA from DNA using RNA polymerase.
Transcription factor -- a protein that regulates the activity of RNA polymerase.
Transfer RNA (tRNA) -- RNA molecules that function as adaptors between amino acids and mRNA during protein synthesis.
转移核糖核酸 -- 核糖核酸的一种,当蛋白质合成时,当氨基酸与信使核糖核酸的转接器。转移核糖核酸与将被送到组装位置的氨基酸共价键结,每一个转移核糖核酸的3’端均为CCA序列,这个序列对蛋白质的合成非常重要,因为转移核糖核酸的3’端正是蛋白质合成时,氨基酸的接受处
Transformation -- The process by which a cell line, that can normally be expected to undergo a limited number of cell divisions before death, becomes immortal; also the process by which isolated foreign DNA is introduced into a cell or bacterium.
Translation -- the synthesis of a polypeptide chain from an mRNA template.
转译 -- 由信使核糖核酸片段合成多肽键的过程
Transgenic organism -- An organism whose genome has been modified by introduction of novel DNA.
Transition -- The substitution of a purine from a puring or a pyrimidine from a pyrimidine.
转换 -- DNA的碱基取代突变,其中一个purine(如Adenine)被另一个purine(如Guanine)所取代,或一个pyrimidine被另一个pyrimidine所取代。
Transversion -- The substitution of a purine from a pyrimidine or vice versa.
转变 -- DNA的碱基取代突变,其中一个purine(如Adenine)被另一个pyrimidine (如thymidine)所取代,或一个pyrimidine被另一个purine所取代。
U
UniGene -- UniGene is an experimental system for automatically partitioning GenBank sequences into a non-redundant set of gene-oriented clusters. Each UniGene cluster contains sequences that represent a unique gene, as well as related information such as the tissue types in which the gene has been expressed and map location.
单基因 -- 单基因为一实验系统,可将基因库序列自动分割成多个非重复的基因导向丛,每个单基因丛含有单基因的序列并含有基因在组织中如何表现与其在染色体的位置
Uracil -- a pyrimidine found in RNA that base-pares with adenine.
尿嘧啶 -- 核糖核酸中的一种嘧啶,与腺嘌呤形成碱基对。