関連する実験動画
Updated: Jul 13, 2026
16:47
Dissection of a Mouse Eye for a Whole Mount of the Retinal Pigment Epithelium
Published on: February 27, 2011
ネズミのピンクアイの希釈遺伝子:人間のプラダー・ウィリー症候群とエンジェルマン症候群との関連
J M Gardner1, Y Nakatsu, Y Gondo
1Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, PA 19111.
Science (New York, N.Y.)
|August 21, 1992
まとめ
研究者らは,ネズミのピンクアイの希釈 (p) 遺伝子を特定し,その障害がヒポピグメンテーションを引き起こすことを発見しました. この遺伝子は,この遺伝子を
科学分野:
- 遺伝学 遺伝学とは
- 分子生物学は分子生物学である.
- 発達生物学 発達生物学とは
背景:
- ネズミの染色体7にあるピンクアイの薄解 (p) 部位は,色素化にとって極めて重要です.
- pロクスの変異により,下色素化現象型が生じる.
研究 の 目的:
- マウスのp局所から補完的なDNA (cDNA) クローンを分離し,特徴づけること.
- p変異体における低色素化フェノタイプの遺伝的基礎を調査する.
- マウスp遺伝子のヒト同類体を特定し,局所化する.
主な方法:
- ネズミのメラノーマとメラノサイト図書館からのcDNAクローンの分離.
- pロクスの6つの独立した突然変異アレルにおける遺伝子発現の分析.
- 染色体マッピング技術を用いてヒトの同類体の局所化.
主要な成果:
- p遺伝子からのトランスクリプトは,すべての6つの変異性アレルで欠落または変化していることが判明しました.
- この遺伝子の障害は,ヒポピグメンテーションのフェノタイプと直接相関しています.
- p遺伝子のヒトホモログは,染色体15q11.2-q11.2.2に局在していた.
結論:
- 特定された遺伝子は,マウスの正常な色素化に不可欠である.
- この遺伝子の変異は,ピンクアイの希釈フェノタイプの原因である.
- プラダー・ウィリー症候群とエンジェルマン症候群の領域の近くにあるヒトの同類体の位置は,これらの疾患における低pigmentationの役割を示唆しています.
関連する概念動画
01:11Genetic Lingo
Overview
01:39Epistasis
In addition to multiple alleles at the same locus influencing traits, numerous genes or alleles at different locations may interact and influence phenotypes in a phenomenon called epistasis. For example, rabbit fur can be black or brown depending on whether the animal is homozygous dominant or heterozygous at a TYRP1 locus. However, if the rabbit is also homozygous recessive at a locus on the tyrosinase gene (TYR), it will have an unshaded coat that appears white, regardless of its TYRP1...
01:33Pleiotropy
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
02:32Position-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.
01:43Incomplete Dominance
Gregor Mendel's work (1822 - 1884) was primarily focused on pea plants. Through his initial experiments, he determined that every gene in a diploid cell has two variants called alleles inherited from each parent. He suggested that amongst these two alleles, one allele is dominant in character and the other recessive. The combination of alleles determines the phenotype of a gene in an organism.
02:41Lethal Alleles
Agouti: A Lethal Allele
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...
Lucien Cuénot discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is responsible for the color of the coat in mice. This gene codes for an agouti-signaling protein, which is responsible for melanin distribution in mammals. The wild-type allele gives rise to gray-brown coat color in mice, while the mutant allele gives rise to yellow coat color. In addition to coat color, the agouti gene is associated with the yellow...