概括
研究人员在基因组中确定了两个不同的人类tRNA-Valine基因. 结构分析揭示了同质性和一个基因中的独特基因替代,为基因组织和进化提供了洞察力.
科学领域:
- 人类基因组学 人类基因组学
- 分子生物学分子生物学
- 基因结构和基因功能
背景情况:
- 人类基因组包含大约12个tRNA-Valine基因,分布在不同的位置.
- 了解这些基因的结构和组织对于理解基因调节和进化至关重要.
研究的目的:
- 描述人类tRNA-Valine基因的结构组织.
- 研究不同tRNA-Valine基因位点及其侧面序列之间的关系.
主要方法:
- 克隆人类胎儿肝脏DNA片段,其中含有tRNA-Valine基因.
- 限制部位映射和电子显微镜对异质双重结构.
- 合同杂交以映射人体纤维细胞体内的体内转录序列.
主要成果:
- 确定了四个DNA片段,代表两个不同的tRNA-Valine基因位点.
- 在染色体社区内分散的重复序列中观察到同质性.
- 详细的分析揭示了非等位基因的近端侧面序列中的同质性块.
- 与常见的脊椎动物tRNA-Valine序列相比,一个基因表现出基因替代 (T为G在56位).
- 与tRNA-Valine结构序列相似的寡核酸被发现在两种基因的5'边界.
结论:
- 人类tRNA-Valine基因位于不同的基因组位置,具有独特的侧翼序列.
- 鉴定的同质和序列变异为基因进化和潜在的调节机制提供了洞察力.
- 在5'侧边区域存在tRNA-Valine样序列,这表明它们在基因调节中的潜在作用,包括转录启动.
更多相关视频
13:55Combined Immunofluorescence and DNA FISH on 3D-preserved Interphase Nuclei to Study Changes in 3D Nuclear Organization
Published on: February 3, 2013
09:32An Array-based Comparative Genomic Hybridization Platform for Efficient Detection of Copy Number Variations in Fast Neutron-induced Medicago truncatula Mutants
Published on: November 8, 2017
相关概念视频
Position-effect Variegation
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
Overview of Transposition and Recombination
Transposons make up a significant part of genomes of various organisms. Therefore, it is believed that transposition played a major evolutionary role in speciation by changing genome sizes and modifying gene expression patterns. For example, in bacteria, transposition can lead to conferring antibiotic resistance. Movement of transposable elements within the genetic pool of pathogenic bacteria can aid in transfer of antibiotic-resistant genetic elements. In eukaryotes, transposons can carry out...
Evolutionary Relationships through Genome Comparisons
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
Synteny and Evolution
John H. Renwick first coined the term “synteny” in 1971, which refers to the genes present on the same chromosomes, even if they are not genetically linked. The species with common ancestry tend to show conserved syntenic regions. Therefore, the concept of synteny is nowadays used to describe the evolutionary relationship between species.
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
Comparing Copy Number Variations and SNPs
Sequencing of the human genome has opened up several best-kept secrets of the genome. Scientists have identified thousands of genome variations that exist within a population. These variations can be a single nucleotide or a larger chromosomal variation.
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
