The loci controlling plasticity in flax
The loci controlling plasticity in flax
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DOI：
10.2147/rrb.s27198
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发表时间：
2012-01-01
期刊：
影响因子：
--
通讯作者：
Cullis, Christopher A.
中科院分区：
文献类型：
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作者：
Bickel, Cory L.;Lukacs, Marshall;Cullis, Christopher A.
亚麻在营养胁迫下发生了可遗传的基因组变化，包括总DNA含量的变化、rDNA拷贝数的变化和亚麻插入序列1（LIS-1）的出现。基因组变化的性质表明，这种机制与响应压力的其他DNA变化（例如转座因子的激活）非常不同，但目前尚不清楚。为了鉴定控制亚麻中响应于胁迫的基因组变化的基因，在响应的亚麻系Stormont cirrus和无响应的亚麻系白求恩之间进行了正反交。使用LIS-1的插入作为响应性的标准来测定F2代（来自自交的F1植物）响应营养胁迫的能力。89个F2中有29个在5周时有反应，这表明3-4个优势位点对于早期LIS-1插入都是必需的。70的76响应在10周，表明两个显性位点独立启动LIS-1插入在长期的营养胁迫下。F_1代植株及其以P_1或白求恩为母本的后代都能对LIS-1插入产生反应，表明LIS-1插入受核遗传控制，不涉及母本因素。因此，斯托蒙特卷云的基因组内的少数位点似乎控制的能力，响应营养胁迫与LIS-1插入。亚麻基因组的遗传图谱目前正在建设中，并将用于确定基因组内的这些位点。
Flax undergoes heritable genomic changes in response to nutrient stress, including changes in total DNA content, rDNA copy number variation, and the appearance of Linum Insertion Sequence 1 (LIS-1). The nature of the genomic changes suggests a very different mechanism, which is not yet understood, from that of other DNA changes in response to stress, such as the activation of transposable elements. To identify the genes that control genomic changes in response to stress in flax, reciprocal crosses were made between a responsive flax line, Stormont cirrus, and an unresponsive line, Bethune. The ability of the F2 generation ( from selfed F1 plants) to respond to nutrient stress was assayed using the insertion of LIS-1 as the criteria for responsiveness. Twenty-nine out of 89 F2s responded at 5 weeks, suggesting that 3-4 dominant loci were all necessary for early LIS-1 insertion. Seventy out of 76 responded at 10 weeks, indicating two dominant loci independently capable of initiating LIS-1 insertion under prolonged nutrient stress. F1 plants and their progeny with either Pl or Bethune as the maternal parent were capable of responding with LIS-1 insertion, indicating that LIS-1 insertion is under nuclear genetic control and does not involve maternal factors. Thus, a small number of loci within the genome of Stormont cirrus appear to control the ability to respond to nutrient stress with LIS-1 insertion. A genetic map of the flax genome is currently under construction, and will be used to identify these loci within the genome.