相关实验视频
Updated: Aug 4, 2026

09:19
In ovo Expression of MicroRNA in Ventral Chick Midbrain
Published on: September 16, 2013
概括
研究人员克隆了一只的DNA,其中包含了ovomucoid基因. 分析发现了基因.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 卵基因对于理解鸟类蛋的形成至关重要.
- 之前的研究集中在蛋白质产品上,但基因结构在很大程度上仍未表征.
研究的目的:
- 为了克隆和表征小卵状基因的5'-部分.
- 为了研究卵基因的结构组织,包括中间序列的存在和数量.
主要方法:
- 使用体外包装将一个含有ovomucoid基因的EcoRIDNA片段克隆为15千基基对的lambda菌体Charon 4A.
- 克隆DNA片段的限制映射.
- 对DNA结构的电子显微镜分析.
主要成果:
- 成功克隆了一个15千基基因对的DNA片段,其中包含了ovomucoid基因的5'-部分和终结编码.
- 限制映射和电子显微镜证实,在卵基因内至少存在六个中间序列 (内子).
- 克隆的DNA片段包括终结密码子 (UGA),并延伸到结构基因的5'-区域.
结论:
- 小卵状基因被干预序列广泛中断.
- 这一发现为进一步研究鸟类物种的卵状基因表达和调节提供了基础.
- 克隆的DNA片段是研究基因结构和进化的宝贵资源.
相关概念视频
Operons
Prokaryotes can control gene expression through operons—DNA sequences consisting of regulatory elements and clustered, functionally related protein-coding genes. Operons use a single promoter sequence to initiate transcription of a gene cluster (i.e., a group of structural genes) into a single mRNA molecule. The terminator sequence ends transcription. An operator sequence, located between the promoter and structural genes, prohibits the operon’s transcriptional activity if bound by a repressor...
Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
Operons
Prokaryotes can control gene expression through operons—DNA sequences consisting of regulatory elements and clustered, functionally related protein-coding genes. Operons use a single promoter sequence to initiate transcription of a gene cluster (i.e., a group of structural genes) into a single mRNA molecule. The terminator sequence ends transcription. An operator sequence, located between the promoter and structural genes, prohibits the operon’s transcriptional activity if bound by a repressor...
Multi-species Conserved Sequences
Next-generation sequencing technologies have created large genomic databases of a variety of animals and plants. Ever since the human genome project was completed, scientists studied the genome of primates, mammals, and other phylogenetically distant living beings. Such large-scale studies have provided new insights into the evolutionary relationship between organisms.
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Although the genome of each species varies greatly from each other, a few sequences are highly conserved. Such conserved DNA...
Exon Recombination
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...

