一个单一的基因导致雄性不育和分离扭曲在Drosophila杂交的混合物
1Department of Biology, University of Rochester, Rochester, NY 14627-0211, USA. pdns@mail.rochester.edu
Science (New York, N.Y.)
|December 17, 2008
概括
过度驱动基因会导致Drosophila pseudoobscura杂交物种的男性不育和分离扭曲. 这种遗传冲突是分种之间物种化和繁殖隔离的关键驱动因素.
科学领域:
- 进化生物学 进化生物学
- 遗传学 是一个遗传学.
- 规范研究研究 规范研究
背景情况:
- 品种化涉及生殖隔离,但推动后胞胎隔离的基因组力量尚不清楚.
- 几种快速进化的基因有助于混合不育性/不可生存性,但它们的生态驱动因素仍然不清楚.
研究的目的:
- 为了确定负责物种化的基因和进化力量.
- 为了调查Drosophila pseudoobscura亚种中后阴性隔离的遗传基础.
主要方法:
- 来自波哥大和美国Drosophila pseudoobscura亚种的混合后代的比较分析.
- 基因映射和功能性研究,以确定导致混合不相容的基因.
主要成果:
- 过度驱动基因被确定为F1杂交品种中男性不育和分离扭曲的原因.
- 这个单一的基因在研究的亚种之间起到强大的繁殖障碍作用.
- 过度驱动的快速进化表明积极的达尔文选择.
结论:
- 遗传冲突,以过度驱动基因为例,是物种化过程中的一个重要的进化力量.
- 了解像Overdrive这样的基因对于破译生殖隔离机制至关重要.
相关概念视频
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Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
01:49Law of Segregation
When crossing pea plants, Mendel noticed that one of the parental traits would sometimes disappear in the first generation of offspring, called the F1 generation, and could reappear in the next generation (F2). He concluded that one of the traits must be dominant over the other, thereby causing masking of one trait in the F1 generation. When he crossed the F1 plants, he found that 75% of the offspring in the F2 generation had the dominant phenotype, while 25% had the recessive phenotype.
02:50Dosage Compensation
In animals, gender is determined by the number and type of sex chromosome. For example, human females have two X chromosomes, and males have one X and one Y chromosome, whereas C.elegans with one X chromosome is a male, and the one with two X chromosomes is a hermaphrodite.
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In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...
02:03Law of Independent Assortment
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01:18Dihybrid Crosses
Overview
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.