假定阴离子交换器SLC24A5影响斑马鱼和人类的色素
Rebecca L Lamason1, Manzoor-Ali P K Mohideen, Jason R Mest
1Jake Gittlen Cancer Research Foundation, Department of Pathology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.
Science (New York, N.Y.)
|December 17, 2005
概括
斑马鱼的金色基因突变会影响黑色素体的发育,类似于更浅的人类皮肤. 人类SLC24A5基因变异与欧洲人群的皮肤颜色较浅有关.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 人类色素化 人类色素化
背景情况:
- 人体较轻的色素与减少的黑色素体数量,大小和密度有关.
- 黑色素体是负责皮肤和头发颜色的关键器官.
研究的目的:
- 为了研究色素差异的遗传基础.
- 确定负责斑马鱼"金色"突变的基因及其在黑色素体生物生成中的作用.
- 探索与皮肤颜色的关系中,人类ortholog,SLC24A5的进化历史和种群遗传学.
主要方法:
- 斑马鱼遗传查和突变分析.
- 基因克隆和测序以识别黄金基因.
- 表达式分析和亚细胞局部化研究.
- 对人类的比较基因组学和人口遗传分析SLC24A5.5.
主要成果:
- 斑马鱼金色突变被确定为slc24a5 (nckx5) 基因中的一个缺陷.
- slc24a5局限于细胞内膜,可能是黑色素体或它们的前体.
- 在功能上,人类的SLC24A5正向标与斑马鱼相似.
- 一个特定的人类SLC24A5等位基因在欧洲人群中普遍存在,并与皮肤更浅和遗传多样性减少有关.
结论:
- SLC24A5在黑色素体生物发生和色素化中起着至关重要的作用.
- 进化保存的SLC24A5基因在人类群体中受到强烈的选择,导致皮肤颜色的变化.
相关概念视频
01:19X-linked Traits
In most mammalian species, females have two X sex chromosomes and males have an X and Y. As a result, mutations on the X chromosome in females may be masked by the presence of a normal allele on the second X. In contrast, a mutation on the X chromosome in males more often causes observable biological defects, as there is no normal X to compensate. Trait variations arising from mutations on the X chromosome are called “X-linked”.
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.
02:27Background and Environment Affect Phenotype
Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
02:32X and Y Chromosomes
Among mammals, the gender of an organism is determined by the sex chromosomes. Humans have two sex chromosomes, X and Y. Every human diploid cell has 22 pairs of autosomes and one pair of sex chromosomes. A human female has two X chromosomes, while a male has one X chromosome and one Y chromosome.
The germline cells such as egg and sperm cells carry only half the number of chromosomes, i.e., 22 autosomes and one sex chromosome. All eggs have an X chromosome, while sperm cells can carry an X or...
The germline cells such as egg and sperm cells carry only half the number of chromosomes, i.e., 22 autosomes and one sex chromosome. All eggs have an X chromosome, while sperm cells can carry an X or...