基因组特征的跨基因双胞胎和小麦的基因组替代形式的细胞遗传特征
E D Badaeva1, R O Davoyan2, N A Tereshchenko1
1N.I. Vavilov Institute of General Genetics of the Russian Academy of Sciences, Moscow, Russia.
Vavilovskii zhurnal genetiki i selektsii
|December 26, 2024
概括
合成小麦杂交品为作物改进提供了有价值的基因. 长期研究表明,八倍体混合体经历了显著的基因组重组,与稳定的六倍体不同,影响了未来的育种应用.
科学领域:
- 植物遗传学和育种.
- 细胞遗传学 细胞遗传学
- 基因组学就是基因组学.
背景情况:
- 合成的两体和基因组替代的小麦对于将野生亲属的基因转移到普通小麦 (Triticum aestivum L.) 中至关重要.
- 这些材料对于学术研究和育种至关重要,使小麦外来添加和替代线路的开发成为可能.
- 这些全聚体的长期稳定性和基因组命运,尤其是在初步验证后,往往是未知的.
研究的目的:
- 分析长期维持的合成小麦两倍体和基因组替代形式的细胞学稳定性和基因组构成.
- 研究随着时间的推移发生在六倍体和八倍体小麦外来杂交物中发生的基因组重组.
- 为了验证特定的小麦-艾吉洛普斯杂交的基因组组成,包括Avrotata.
主要方法:
- 六倍体 (2n=6x=42) 和八倍体 (2n=8x=56) 两倍体和基因组替代的小麦形式的型分析.
- 使用pAs1和pSc119.2探针进行染色体识别的C-绑定和光 in situ杂交 (FISH).
- 在六倍体和八倍体小麦外来杂交物之间对细胞稳定性的比较分析.
主要成果:
- 大多数分析的两类动物和基因组替代形式在细胞学上是稳定的,除了像Avrodes这样的例外,它显示了染色体组成的分离.
- 对Avrotata的染色体分析没有证实Aegilops uniaristata的N基因组存在;相反,它携带的是D基因组.
- 八倍化小麦-艾吉洛普斯杂交物 (公元7年,公元7147年) 呈现出更复杂的基因组重组,通过从不同的父母亚基因组中失去七对染色体,减少到六倍化水平.
结论:
- 长期维护显示合成小麦全聚聚体的基因组稳定性差异,八聚体经历了实质性的重组.
- 这项研究澄清了特定杂交物种的基因组组成,纠正了以前的假设 (例如,Avrotata).
- 在八倍体中观察到的基因组减少和重组会产生具有独特染色体组合的新型六倍体合成/混合基因组,为小麦育种提供新的途径.
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