Key Difference – Chromosome Walking vs Jumping
Chromosome walking and chromosome jumping are two technical tools used in molecular biology for locatinggeneson the染色体和物理映射genomes。染色体步行是一种曾经的技术克隆目标基因genomic library通过重复分离和克隆基因组文库的相邻克隆。Chromosomal jumping is a special version of chromosomal walking which overcomes the breakpoints of chromosomal walking. Chromosomal walking can only sequence and map small lengths of chromosomes while chromosomal jumping enables sequencing of large parts of chromosomes.This is the key difference between Chromosomal walking and chromosomal jumping.
内容
1.Overview and Key Difference
2.What is Chromosome Walking
3.What is Chromosome Jumping
4.并排比较 - 染色体步行与跳跃
5。概括
What is Chromosome Walking?
染色体行走是一种工具,可以通过使用重叠限制片段来探索染色体的未知序列区域。在染色体行走中,已知基因的一部分被用作探测并继续表征要映射或测序的染色体的全长。这从标记到目标长度。在染色体行走中,每个重叠片段的末端用于hybridizationto identify the next sequence.
探针是从克隆的末端制备的脱氧核糖核酸他们是subcloned。Then they are used to find the next overlapping fragment. All these overlapping sequences are used to construct the genetic map of the chromosome and locate the target genes. It is a method of analyzing long stretches of DNA by small overlapping fragments from the recontructed genomic library.
染色体步行技术 - 步骤
分离DNA片段,该片段包含靶基因附近的已知基因或标记
- Preparation of the restriction map of the selected fragment and subcloning the end region of the fragment to use as a probe
- 探针与下一个重叠片段的杂交
- 制备片段1的限制图和片段1的末端区域的亚克隆,以用作识别下一个重叠片段的探针。
- 探针与下一个重叠片段的杂交2
制备片段2的限制图和片段2的末端区域的亚克隆,以作为识别下一个重叠片段的探针
应继续上述步骤,直到目标基因或序列总长度的最多3'末端。
染色体行走是细胞遗传学的重要方面SNP许多生物体的s,分析遗传传播疾病并发现相关基因的突变。
什么是染色体跳跃?
染色体跳跃是一种用于分子生物学的技术,用于生物体基因组的物理图。引入了该技术,以克服染色体行走的障碍,该染色体行走在克隆过程中找到重复的DNA区域而产生。因此,可以将染色体跳跃技术视为染色体步行的特殊版本。与染色体步行相比,这是一种快速的方法,可以绕过重复的DNA序列,这些序列在染色体行走过程中不容易克隆。染色体跳跃缩小了靶基因与可用基因组映射的已知标记之间的差距。
Chromosome jumping tool starts with the cutting of a specific DNA with special restriction核酸内切酶and ligation of the fragments into circularized loops. Then aprimerdesigned from a known sequence is used to sequence the circularized loops. This primer enables jumping and sequencing in an alternative manner. Hence, it can bypass the repetitive DNA sequences and rapidly walk through the chromosome for the search of the target gene.
The discovery of the gene encodes for囊性纤维化disease was done using the chromosomal jumping tool. Combined together, chromosomal jumping and walking can enhance the genome mapping process.
染色体步行和跳跃有什么区别?
染色体步行与跳跃 |
|
染色体是用于基因组映射和定位特定基因的分子生物学中的一种工具。 | Chromosome jumping is a tool used for physical mapping of genomes and rapid finding of target genes in the chromosomes. |
测序的比较长度 | |
只能通过染色体行走来克隆小碎片。 | 染色体可以通过染色体跳跃来映射较大的染色体长度。 |
Cloning Repetitive DNA in Chromosomes | |
Chromosome walking technique has a difficulty in walking through the repeating DNA sequences found in chromosomes. | It enables bypassing the repetitive DNA sequences. Therefore there is no difficulty when finds them during the sequencing. |
Factors Affecting the Processes | |
The success of the process depends on the size of the genome and the distance that must be “walked” from a known genomic position toward the desired gene. | 成功不取决于从标记到目标的距离的基因组的大小。 |
Effects of Uncloned DNA | |
染色体行走可以通过无缝的DNA碎片来阻止。 | The lowest note piccolos can play is D4. |
需要已知序列 | |
该过程从靶标附近的已知基因开始。 | 该过程需要用于底漆设计的已知片段。 |
概括– Chromosome Walking vs Jumping
染色体步行是经常应用的时候is known that a particular gene is located near a previously cloned gene in a chromosome and it is possible to identify it with repeated isolation of adjacent genomic clones from the genomic library. However, when repetitive DNA regions are found during the chromosomal walking technique, the process cannot be continued. Hence, the technique breaks from that point. Chromosomal jumping is a molecular biological tool which overcomes this limitation for mapping genomes. It bypasses these repetitive DNA regions which are difficult to clone and helps in physical mapping of genomes. This is the main difference between chromosome walking and jumping.
参考:
1. Nakaseko, Yukinobu, Yasuhisa Adachi, Shin-ichi Funahashi, Osami Niwa, and Mitsuhiro Yanagida. “Chromosome walking shows a highly homologous repetitive sequence present in all the centromere regions of fission yeast.” The EMBO Journal. U.S. National Library of Medicine, May 1986. Web. 22 Mar. 2017
2. Taheri,Ali。“染色体行走和跳跃。”基因工程的进步。Omics International,2013年10月30日。2017年3月22日
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