Alcázar Rubén, von Reth Marcel, Bautor Jaqueline, Chae Eunyoung, Weigel Detlef, Koornneef Maarten, Parker Jane E
Department of Natural Products, Plant Biology and Soil Science, Laboratory of Plant Physiology, Faculty of Pharmacy. University of Barcelona, Barcelona, Spain; Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, Germany; Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany.
Department of Plant-Microbe Interactions, Max Planck Institute for Plant Breeding Research, Cologne, Germany; Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, Cologne, Germany.
PLoS Genet. 2014 Dec 11;10(12):e1004848. doi: 10.1371/journal.pgen.1004848. eCollection 2014 Dec.
Mechanisms underlying speciation in plants include detrimental (incompatible) genetic interactions between parental alleles that incur a fitness cost in hybrids. We reported on recessive hybrid incompatibility between an Arabidopsis thaliana strain from Poland, Landsberg erecta (Ler), and many Central Asian A. thaliana strains. The incompatible interaction is determined by a polymorphic cluster of Toll/interleukin-1 receptor-nucleotide binding-leucine rich repeat (TNL) RPP1 (Recognition of Peronospora parasitica1)-like genes in Ler and alleles of the receptor-like kinase Strubbelig Receptor Family 3 (SRF3) in Central Asian strains Kas-2 or Kond, causing temperature-dependent autoimmunity and loss of growth and reproductive fitness. Here, we genetically dissected the RPP1-like Ler locus to determine contributions of individual RPP1-like Ler (R1-R8) genes to the incompatibility. In a neutral background, expression of most RPP1-like Ler genes, except R3, has no effect on growth or pathogen resistance. Incompatibility involves increased R3 expression and engineered R3 overexpression in a neutral background induces dwarfism and sterility. However, no individual RPP1-like Ler gene is sufficient for incompatibility between Ler and Kas-2 or Kond, suggesting that co-action of at least two RPP1-like members underlies this epistatic interaction. We find that the RPP1-like Ler haplotype is frequent and occurs with other Ler RPP1-like alleles in a local population in Gorzów Wielkopolski (Poland). Only Gorzów individuals carrying the RPP1-like Ler haplotype are incompatible with Kas-2 and Kond, whereas other RPP1-like alleles in the population are compatible. Therefore, the RPP1-like Ler haplotype has been maintained in genetically different individuals at a single site, allowing exploration of forces shaping the evolution of RPP1-like genes at local and regional population scales.
植物物种形成的潜在机制包括亲本等位基因之间有害（不兼容）的遗传相互作用，这种相互作用会给杂种带来适合度代价。我们报道了来自波兰的拟南芥品系直立叶兰茨贝格（Ler）与许多中亚拟南芥品系之间的隐性杂种不亲和性。这种不兼容的相互作用由Ler中Toll/白细胞介素-1受体-核苷酸结合-富含亮氨酸重复序列（TNL）的RPP1（寄生霜霉识别蛋白1）样基因的多态性簇以及中亚品系Kas-2或Kond中类受体激酶Strubbelig受体家族3（SRF3）的等位基因决定，导致温度依赖性自身免疫以及生长和繁殖适合度丧失。在此，我们对RPP1样Ler位点进行了遗传剖析，以确定各个RPP1样Ler（R1-R8）基因对不亲和性的贡献。在中性背景下，除R3外，大多数RPP1样Ler基因的表达对生长或病原体抗性没有影响。不亲和性涉及R3表达增加，并且在中性背景下通过工程手段使R3过表达会诱导矮化和不育。然而，但没有单个RPP1样Ler基因足以导致Ler与Kas-2或Kond之间的不亲和性，这表明至少两个RPP1样成员的共同作用是这种上位性相互作用的基础。我们发现RPP1样Ler单倍型很常见，并且在波兰大波兰地区戈尔佐夫的一个当地种群中与其他Ler RPP1样等位基因一起出现。只有携带RPP1样Ler单倍型的戈尔佐夫个体与Kas-2和Kond不亲和，而种群中的其他RPP1样等位基因是兼容的。因此，RPP1样Ler单倍型在单个位点的遗传不同个体中得以维持，可以探究在局部和区域种群尺度上塑造RPP1样基因进化的力量。
