Ph1作为多倍体小麦中主要染色体配对位置的分子表征
Simon Griffiths1, Rebecca Sharp, Tracie N Foote
1John Innes Centre, Colney, Norwich NR4 7UH, UK.
Nature
|February 10, 2006
概括
对于小麦生育能力至关重要的Ph1位点已被确定为5B染色体上的特定区域. 这个区域包含一个独特的结构,涉及异色染色素和cdc2基因,可能负责其介质配对控制.
科学领域:
- 遗传学 是一个遗传学.
- 植物生物学 植物生物学
- 分子生物学分子生物学
背景情况:
- 面包小麦的高肥力依赖于一个稳定的多倍体基因组.
- 小麦物种 (六倍体和四倍体) 在化过程中表现出类似双倍体的行为,由Ph1位点控制.
- 在小麦杂交物中,Ph1位点阻止了相关染色体之间的配对.
研究的目的:
- 为了定位Ph1的位置.
- 了解Ph1活动的结构基础及其在小麦半变化中的作用.
主要方法:
- 基因测绘以精确确定Ph1的位置.
- 对小麦5B染色体结构的分析.
- 相关小麦物种的比较基因组学.
主要成果:
- Ph1位点定位在小麦5B染色体上的2.5兆基间歇区域.
- 这一区域包含了一个结构,其中的子端粒异色素被插入到与cdc2相关的基因中.
- 这种结构的存在与相关物种中的Ph1活性相关.
结论:
- 已识别的结构是Ph1位点的强有力的候选者.
- 这种结构很可能是在多化过程中产生的,对小麦中介性稳定性至关重要.
- 了解Ph1的结构,可以了解小麦基因组的进化和生育能力.
相关概念视频
01:20Monohybrid Crosses
Overview
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.
01:15The Antenna Complex
Plants and other photosynthetic organisms comprise pigments capable of absorption of direct sunlight. These pigments are present in the reaction center - the main site of photochemical reactions as well as in the antenna complex. Under average light conditions, the rate at which reaction center pigments absorb light is far below the electron transport chain's capacity. As a result, the reaction center alone cannot provide enough energy to drive photosynthesis. The photosynthetic efficiency can...
02:27Trihybrid Crosses
Trihybrid Crosses
Some of Mendel’s crosses examined three pairs of contrasting characteristics. Such a cross is called a trihybrid cross. A trihybrid cross is a combination of three individual monohybrid crosses. For example, plant height (tall vs. short), seed shape (round vs. wrinkled), and seed color (yellow vs. green).
The F1 generation plants of a trihybrid cross are heterozygous for all three traits and produce eight gametes. Upon self-fertilization, these gametes have an equal chance to...
Some of Mendel’s crosses examined three pairs of contrasting characteristics. Such a cross is called a trihybrid cross. A trihybrid cross is a combination of three individual monohybrid crosses. For example, plant height (tall vs. short), seed shape (round vs. wrinkled), and seed color (yellow vs. green).
The F1 generation plants of a trihybrid cross are heterozygous for all three traits and produce eight gametes. Upon self-fertilization, these gametes have an equal chance to...