小鼠的粉红眼稀释基因:与人类的普拉德-威利和安吉尔曼综合征有关
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
概括
研究人员在小鼠中确定了粉红眼稀释 (p) 基因,发现其破坏会导致低颜色化. 这个基因,这个基因.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 发展生物学 发展生物学
背景情况:
- 鼠标染色体7上的粉红眼稀释 (p) 位点对于色素来说至关重要.
- 在p位点的突变导致低颜色化表型.
研究的目的:
- 从小鼠p locus中分离和表征互补DNA (cDNA) 克隆.
- 调查p突变体中低颜色化表型的遗传基础.
- 识别和定位小鼠p基因的人类同类.
主要方法:
- 从小鼠黑色素瘤和黑色素细胞库中分离cDNA克隆.
- 在六个独立突变的p位点的基因表达的分析.
- 使用染色体映射技术定位人类同类物.
主要成果:
- 发现p基因的转录在所有六个突变基因中都缺失或改变.
- 这种基因的破坏与低颜色化表型直接相关.
- 这种p基因的人类同类被定位在染色体15q11.2-q11.2.2.上.
结论:
- 鉴定出来的基因对于小鼠的正常色素是必不可少的.
- 这个基因的改变是粉红眼稀释表型的原因.
- 人类同类在普拉德-威利和安吉尔曼综合征区域附近的位置表明,在这些疾病中,低颜色素有作用.
相关概念视频
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...