Complex Rearrangements Lead to Novel Chimeric Gene Fusion Polymorphisms at the Arabidopsis thaliana MAF2-5 Flowering Time Gene Cluster
Complex Rearrangements Lead to Novel Chimeric Gene Fusion Polymorphisms at the Arabidopsis thaliana MAF2-5 Flowering Time Gene Cluster
复制标题
DOI：
10.1093/molbev/msn300
复制
发表时间：
2009-03-01
影响因子：
10.7
通讯作者：
Purugganan, Michael D.
中科院分区：
文献类型：
--
作者：
Caicedo, Ana L.;Richards, Christina;Purugganan, Michael D.
多基因家族的串联基因簇是基因重排的热点，可能是新基因形成的重要来源。在这里，我们报告的模式植物物种，拟南芥的MAF 2 -5基因簇的分子群体遗传分析。MAF 2 -5基因是MADS盒多基因家族簇，在5号染色体上跨越类似于24 kbp。我们发现这些基因之间的异质进化动力学，所有这些基因都与花抑制因子FLC密切相关，并被认为在控制开花时间中起作用。thaliana.低水平的非同义单核苷酸多态性（SNP）观察MAF 4和MAF 5表明纯化选择和功能的保护。相反，在MAF 2和MAF 3中观察到高水平的非同义SNP、插入-缺失和重排，包括在A. thaliana.这些融合的基因，涉及MAF 2和部分MAF 3，表达，导致嵌合的，选择性剪接的转录MAF 2的生产。关联研究支持所描述的MAF 2-MAF 3基因重排和开花时间的物种之间的相关性。发现基因簇内的复杂重排，如MAF 2观察到的那些，可能在产生生态重要的表型变异中发挥作用，强调需要新兴的高通量基因分型和测序技术，以正确地重建基因嵌合体和其他复杂的多态性。
Tandem gene clusters of multigene families are rearrangement hotspots and may be a major source of novel gene formation. Here, we report on a molecular population genetic analysis of the MAF2-5 gene cluster of the model plant species, Arabidopsis thaliana. The MAF2-5 genes are a MADS-box multigene family cluster spanning similar to 24 kbp on chromosome 5. We find heterogeneous evolutionary dynamics among these genes, all of which are closely related to the floral repressor, FLC, and are believed to play a role in the control of flowering time in A. thaliana. Low levels of nonsynonymous single nucleotide polymorphism (SNP) observed for MAF4 and MAF5 suggest purifying selection and conservation of function. In contrast, high levels of nonsynonymous SNPs, insertion-deletion, and rearrangements are observed for MAF2 and MAF3, including novel gene fusions that persist as a moderate-frequency polymorphism in A. thaliana. These fused genes, involving MAF2 and portions of MAF3, are expressed, resulting in the production of chimeric, alternatively spliced transcripts of MAF2. Association studies support a correlation between the described MAF2-MAF3 gene rearrangements and flowering time variation in the species. The finding that complex rearrangements within gene clusters, such as those observed for MAF2, might play a role in the generation of ecologically important phenotypic variation, emphasize the need for emerging high throughput genotyping and sequencing techniques to correctly reconstruct gene chimeras and other complex polymorphisms.