Characterization of pectate lyase gene family in Fusarium oxysporum f. sp. Lycopersici genome and expression mode during inoculation

Abstract:

[Background] Tomato fusarium wilt is a common soil born fungal disease in tomato production. [Objective] To identify pectate lyase gene family members in Fusarium oxysporum f. sp. Lycopersici genome and to clarify the expression mode after inoculation.[Methods] PEL family was identified, and the distribution, physical and chemical properties, gene structure, and tertiary structure prediction of PELs in F. oxysporm f. sp. Lycopersici genome were performed by bioinformatics. Expression mode of FoPEL1−16 in inoculated tomato roots were analyzed by RT-qPCR. [Results] There were 16 FoPELs in F. oxysporm f. sp. Lycopersici genome. The amino acid sequences were 163−548 aa in length with 16−21 aa signal peptides. The FoPEL genes were unevenly distributed on 7 chromosomes. 16 FoPELs were divided into four groups according to gene structure and conserved motifs. Evolutionary analysis showed that FoPELs clustered in four clades. Similar domain structure presented in the same family according to tertiary structure prediction. RT-qPCR analysis showed that FoPEL expression levels significantly increased during inoculation. [Conclusion] The pectate lyase existed in the form of gene family in F. oxysporm f. sp. Lycopersici genome, and the difference of gene structure indicated their function diversity. The expression levels of FoPEL were significantly increased during infection, which indicated that FoPEL was involved in the pathogenicity. The study provided a theoretical basis for pathogenic gene function and plant-pathogen interaction of F. oxysporium.

Key words:Fusarium wilt;pectate lyase;genome;gene family