Sela-Buurlage M B, Budai-Hadrian O, Pan Q, Carmel-Goren L, Vunsch R, Zamir D, Fluhr R
Department of Plant Sciences, Weizmann Institute of Science, Rehovot, Israel.
Mol Genet Genomics. 2001 Aug;265(6):1104-11. doi: 10.1007/s004380100509.
Resistance to different pathogenic races of Fusarium oxysporum f. sp. lycopersici (F. o. lycopersici) was explored at two genomic levels in tomato. Six independent Fusarium resistance loci were identified by comparing the responses of a complete set of 53 lines carrying different introgressed regions of the Lycopersicon pennellii genome in a L. esculentum background. The loci confer varying degrees of resistance to different races of the pathogen. Corresponding map positions from different tomato species were aligned and in some cases revealed parallel resistance to F. o. lycopersici with qualitative changes in race specificities. One of the loci identified corresponds to the previously characterized complex resistance locus I2, which is involved in resistance to F. o. lycopersici race 2. A novel member of this locus, I2C-5, which belongs to the NBS-LRR family of resistance genes, was cloned and shown to confer partial resistance in transgenic plants. Thus, at a particular complex locus gene members can confer full or partial resistance to F. o. lycopersici race 2. The results of our whole-genome mapping analysis underline the robust independent origin of resistance to a particular disease and demonstrate the conservation of resistance features at syntenic loci, together with the rapid diversification of genes for innate resistance within loci.
在番茄的两个基因组水平上探究了对尖孢镰刀菌番茄专化型（F. o. lycopersici）不同致病小种的抗性。通过比较53个品系在番茄背景下携带潘那利番茄（Lycopersicon pennellii）基因组不同渐渗区域的全套品系的反应，鉴定出了6个独立的镰刀菌抗性位点。这些位点对病原菌的不同小种具有不同程度的抗性。对来自不同番茄物种的相应图谱位置进行了比对，在某些情况下揭示了对F. o. lycopersici的平行抗性以及小种特异性的定性变化。鉴定出的其中一个位点对应于先前表征的复杂抗性位点I2，它参与对F. o. lycopersici小种2的抗性。该位点的一个新成员I2C - 5，属于抗性基因的NBS - LRR家族，被克隆并在转基因植物中表现出部分抗性。因此，在一个特定的复杂位点，基因成员可以对F. o. lycopersici小种2赋予完全或部分抗性。我们全基因组图谱分析的结果强调了对特定疾病抗性强大的独立起源，并证明了同线位点抗性特征的保守性，以及位点内固有抗性基因的快速多样化。
