関連する実験動画
Updated: Aug 24, 2026

11:06
Identifying DNA Mutations in Purified Hematopoietic Stem/Progenitor Cells
Published on: February 24, 2014
まとめ
研究者は,乳糖抑制遺伝子 (lacI) プロモーターと乳糖抑制遺伝子プロモーターを配列化した.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 遺伝子規制 遺伝子規制
背景:
- ラクトース抑制遺伝子 (lacI) は,構成的に発現する遺伝子である.
- 遺伝子の調節を理解することは,様々な生物学的プロセスにとって極めて重要です.
研究 の 目的:
- 弱発現のLACI遺伝子のプロモーター領域をシーケンシングする.
- LACI発現を高める"アップ"プロモーター変異 (Iq) の遺伝的基礎を特定する.
主な方法:
- LACLプロモーターとIQミュータントのDNA配列解析.
- 配列化を助けるために,LacI遺伝子を小さなプラズミッドにクローンする.
主要な成果:
- lacIプロモーターとIQ変異は順序付けに成功しました.
- -35の位置での単一の塩基変化が,IQ変異体におけるLACI発現の10倍の増加の原因として特定されました.
結論:
- プロモーター領域の特定の塩基の変化は,遺伝子発現を大幅に高めます.
- この発見は,遺伝子プロモーターの調節のメカニズムについての洞察を提供します.
関連する概念動画
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...
Conservative Site-specific Recombination and Phase Variation
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
The Eukaryotic Promoter Region
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...
The Eukaryotic Promoter Region
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...
Operon Model
The operon model represents a fundamental mechanism of gene regulation in prokaryotes, enabling coordinated expression of genes involved in related metabolic or functional pathways. Operons consist of structural genes, a promoter, and an operator, with transcription regulated by repressors, activators, and small effector molecules.Structure and Function of OperonsAn operon is a cluster of structural genes transcribed together under the control of a single promoter. The promoter region...
Inducible Operons: lac Operon
The lac operon in Escherichia coli is a model for understanding inducible gene regulation and metabolic flexibility. It integrates local control by lactose and global regulation through catabolite repression, enabling E. coli to preferentially metabolize glucose when available and switch to lactose utilization when glucose is scarce.Structure and Function of the lac OperonThe lac operon contains three structural genes: lacZ (β-galactosidase), lacY (lactose permease), and lacA (thiogalactoside...

