関連する実験動画
Updated: Jun 27, 2026

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Long-term In Vivo Tracking of Inflammatory Cell Dynamics Within Drosophila Pupae
Published on: June 14, 2018
ドロソフィラの粘着タンパク質をコードする拡張性遺伝子は,リモートアップストリーム配列が欠けている変種では発現しません
Cell
|July 1, 1982
まとめ
ドロソフィラ・メラノガスターの遺伝的変異
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
- 発達生物学 発達生物学とは
背景:
- ドロソフィラ・メラノガスター遺伝子のSgs4は,幼虫の唾液腺における粘着ポリペプチド (sgs-4) の合成に不可欠である.
- Sgs4遺伝子発現とsgs-4ポリペプチド生成は,幼虫の発達と結合に不可欠です.
研究 の 目的:
- 異なるドロソフィラ・メラロノガスター菌株におけるSgs4遺伝子の構造的および発現的変異を調査する.
- 非生産者株におけるsgs-4mRNAの欠如または少量の遺伝的根拠を特定する.
主な方法:
- 生産者および非生産者ドロソフィラ菌株におけるSgs4遺伝子構造とmRNAレベルの比較分析.
- Sgs4遺伝子の上流のデレーションと構造的変異を特定するためにDNAシーケンシング.
- Sgs4遺伝子発現に関連したDNAase I過敏部位の分析.
主要な成果:
- Sgs4遺伝子の構造は,タンデム21bpの繰り返しによる長さの変化を示しており,タンパク質とmRNAの長さに影響するが,豊富には影響しない.
- 非産生菌株は,sgs-4 mRNAが著しく減少または欠落しており,上流のDNA削除と相関しています.
- 非生産株 (日本株およびBER-1) の削除は,Sgs4.4より上流で唾液腺特異的DNAase I過敏性サイトを含む.
結論:
- アップストリームDNAの削除,特にDNAアゼI過敏部位などの調節要素に影響を与えるものは,非生産性ドロソフィラ菌株におけるSgs4遺伝子発現の欠如に起因する.
- Sgs4のコーディングシーケンス内のタンデムリピートの数は,ポリペプチドとmRNAの長さに影響するが,発現レベルには影響しない.
- この研究は,Drosophila melanogaster.の遺伝子発現を制御する上流の規制領域の重要性を強調しています.
関連する概念動画
Genome Size and the Evolution of New Genes
While every living organism has a genome of some kind (be it RNA, or DNA), there is considerable variation in the sizes of these blueprints. One major factor that impacts genome size is whether the organism is prokaryotic or eukaryotic. In prokaryotes, the genome contains little to no non-coding sequence, such that genes are tightly clustered in groups or operons sequentially along the chromosome. Conversely, the genes in eukaryotes are punctuated by long stretches of non-coding sequence.
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.
DNA-only Transposons
DNA-only transposons are called autonomous transposons since they code for the enzyme transposase that is required for the transposition mechanism. Insertion of transposons can alter gene functions in multiple ways. They can mutate the gene, alter gene expression by introducing a novel promoter or insulator sequence, introduce new splice sites, and change the mRNA transcripts produced, or remodel chromatin structure.
The donor site from where the transposon is excised is either degraded or...
The donor site from where the transposon is excised is either degraded or...
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...
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...
Reporter Genes
Reporter genes are a type of protein-coding gene that are often tagged to a gene of interest. Once inside a target cell, reporter genes usually produce visually identifiable characteristics like fluorescence and luminescence when expressed along with the gene of interest. Thus, reporter genes “report” the presence or absence of genes of interest in an organism, determine the gene expression pattern, or track the physical location of a DNA segment or protein in the cell.
Commonly used reporter...
Commonly used reporter...

