相关实验视频
Updated: Jul 11, 2026
08:10
Environmentally Induced Heritable Changes in Flax
Published on: January 26, 2011
一种表观遗传突变,负责花对称性的自然变化
Nature
|September 18, 1999
概括
表观遗传变化,特别是DNA甲基化,可以在自然种群中引起显著的花突变. 这项研究表明,Lcyc基因中的罕见甲基化缺陷解释了Linaria vulgaris的250年历史的花对称性突变.
科学领域:
- 进化生物学 进化生物学
- 植物遗传学 植物遗传学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 实验室突变的分子研究与自然种群不同.
- 了解自然突变对于进化见解至关重要.
研究的目的:
- 描述一个自然的Linaria vulgaris突变体与改变的花的对称性.
- 研究这种突变的遗传和表观遗传基础.
主要方法:
- 突变的Linaria vulgaris的表型特征.
- 对Lcyc基因的分子分析,Lcyc基因是Antirrhinum cycloidea的同类物.
- DNA甲基化分析和基因表达研究.
主要成果:
- 突变者表现出半径对称而不是双边对称.
- 一个Lcyc基因的缺陷,以广泛的甲基化和沉默为特征,导致突变.
- 这种表观遗传修饰是可遗传的,并与表型共同分离.
- 身体逆转与Lcyc脱甲基化和恢复基因表达相关.
结论:
- 表观遗传突变,特别是DNA甲基化,可以推动自然种群的进化变化.
- 甲基化是一个重要的,但经常被忽视的,产生遗传形态变异的机制.
- 这项研究强调了表观遗传学在进化中的重要性,挑战了以前关于其稀有性的假设.
相关概念视频
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.
03:33Genetic Drift
Natural selection—probably the most well-known evolutionary mechanism—increases the prevalence of traits that enhance survival and reproduction. However, evolution does not merely propagate favorable traits, nor does it always benefit populations.Life is not fair. A deer grazing contentedly in a field can have her meal cut tragically short by a bolt of lightning. If the doomed doe is one of only three in the population, 1/3 of the population’s gene pool is lost. Random events like this can...
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.
02:08Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
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.
02:08Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...