Shi Jian Lei, Zai Wen Shan, Xiong Zhi Li, Wan Hong Jian, Wu Wei Ren
Fujian Provincial Key Laboratory of Crop Breeding by Design, College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, China.
Wenzhou Vocational College of Science and Technology, Wenzhou, China.
Planta. 2021 Oct 16;254(5):96. doi: 10.1007/s00425-021-03745-7.
NB-LRR genes in the three Solanum species showed specific constitution characteristics and evolved multiple clusters and duplicates. Some genes could respond to biotic stresses such as tomato bacterial wilt. Nucleotide-binding and leucine-rich repeat (NB-LRR, NLR) is a largest resistance gene family in plants, which plays a key role in response to biotic stresses. In this study, NB-LRR genes in cultivated tomato Solanum lycopersicum (Sl) and its wild relatives S. pennellii (Spe) and S. pimpinellifolium (Spi) were analyzed using bioinformatics approaches. In total, 238, 202 and 217 NB-LRR genes of 8 different types were found in Sl, Spe and Spi, respectively. The three species showed similar genomic characteristics. The NB-LRR genes were mainly distributed on chromosomes 4, 5 and 11 and located at the distal zones, forming multiple clusters and tandem duplicates. A large number of homologs appeared through gene expansion, with most Ka/Ks values being less than 1, indicating that purifying selection had occurred in evolution. These genes were mainly expressed in root and could respond to different biotic stresses. RT-qPCR analysis revealed that SlNLR genes could respond to tomato bacterial wilt, with SlNLR1 probably involved in the resistance response, whereas others being the opposite. The transcription factors (TFs) and interaction proteins that regulate target genes were mainly Dof, NAC and MYB families and kinases. The results provide a basis for the isolation and application of related genes in plant disease resistance breeding.
三种茄属植物中的NB-LRR基因呈现出特定的构成特征，并进化出多个簇和重复基因。一些基因能够对诸如番茄青枯病等生物胁迫作出反应。核苷酸结合富含亮氨酸重复序列（NB-LRR，NLR）是植物中最大的抗性基因家族，在应对生物胁迫中起关键作用。在本研究中，利用生物信息学方法分析了栽培番茄（Solanum lycopersicum，Sl）及其野生近缘种彭奈利番茄（S. pennellii，Spe）和醋栗番茄（S. pimpinellifolium，Spi）中的NB-LRR基因。分别在Sl、Spe和Spi中总共发现了8种不同类型的238个、202个和217个NB-LRR基因。这三个物种表现出相似的基因组特征。NB-LRR基因主要分布在4号、5号和11号染色体上，并位于远端区域，形成多个簇和串联重复。通过基因扩增出现了大量同源物，大多数Ka/Ks值小于1，表明在进化过程中发生了纯化选择。这些基因主要在根中表达，并能对不同的生物胁迫作出反应。RT-qPCR分析表明，SlNLR基因能够对番茄青枯病作出反应，其中SlNLR1可能参与抗性反应，而其他基因则相反。调控靶基因的转录因子（TFs）和相互作用蛋白主要是Dof、NAC和MYB家族以及激酶。这些结果为植物抗病育种中相关基因的分离和应用提供了依据。
