Overexpression of PtDefensin enhances resistance to Septotis populiperda in transgenic poplar. (March 2020)

• Record Type: Journal Article
• Authors: Wei, Hui; Movahedi, Ali; Xu, Chen; Sun, Weibo; Wang, Xiaoli; Li, Dawei; Zhuge, Qiang
• Is Part Of: Plant science. Volume 292(2020)
• Publication Date: 2020-03
• Subjects: Populus trichocarpa -- PtDefensin -- MYC2 -- JAZ -- SAR -- Septotis populiperda; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2019.110379
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: Overexpression of PtDefensin increased resistance to Septotis populiperda . Overexpression of PtDefensin upregulated of MYC2 related to jasmonic acid. Overexpression of PtDefens in may improve the resistance of plants to pathogens. Abstract: Plant defensins have been implicated in the plant defense system, but their role in poplar immunity is still unclear. In the present study, we present evidence that PtDefensin, a putative plant defensin, participates in the defense of poplar plants against Septotis populiperda infection. After the construction of recombinant plasmid PET-32a- PtDefensin, PtDefensin protein was expressed in Escherichia coli strain BL21 (DE3) and purified through Ni-IDA resin affinity chromatography. The Trx-PtDefensin fusion protein displayed no cytotoxic activity against RAW264.7 cells but had cytotoxic activity against E . coli K12D31 cells. Analyses of PtDefensin transcript abundance showed that the expression levels of PtDefensin responded to abiotic and biotic stresses. Overexpression of PtDefensin in 'Nanlin 895' poplars ( Populus × euramericana cv 'Nanlin895') increased resistance to Septotis populiperda, coupled with upregulation of MYC2 (basic helix-loop-helix (bHLH) transcription factor) related to jasmonic acid (JA) signal transduction pathways and downregulation of Jasmonate-zim domain (JAZ), an inhibitor in the JA signal transduction pathway. We speculate that systemic acquired resistance (SAR) was activated in non-transgenic poplars after S . populiperda incubation, and that induced systemic resistance (ISR) was activated more obviously in transgenic poplars after S . populiperda incubation. Hence, overexpression of PtDefensin may improve the resistance of poplar plants to pathogens.