Cotton Major Latex Protein 28 Functions as a Positive Regulator of the Ethylene Responsive Factor 6 in Defense against Verticillium dahliae

Abstract

In this study, we identified a defense-related major latex protein (MLP) from upland cotton (designated GhMLP28) and investigated its functional mechanism. GhMLP28 transcripts were ubiquitously present in cotton plants, with higher accumulation in the root. Expression of the GhMLP28 gene was induced by Verticillium dahliae inoculation and was responsive to defense signaling molecules, including ethylene, jasmonic acid, and salicylic acid. Knockdown of GhMLP28 expression by virus-induced gene silencing resulted in increased susceptibility of cotton plants to V. dahliae infection, while ectopic overexpression of GhMLP28 in tobacco improved the disease tolerance of the transgenic plants. Further analysis revealed that GhMLP28 interacted with cotton ethylene response factor 6 (GhERF6) and facilitated the binding of GhERF6 to GCC-box element. Transient expression assay demonstrated that GhMLP28 enhanced the transcription factor activity of GhERF6, which led to the augmented expression of some GCC-box genes. GhMLP28 proteins were located in both the nucleus and cytoplasm and their nuclear distribution was dependent on the presence of GhERF6. Collectively, these results demonstrate that GhMLP28 acts as a positive regulator of GhERF6, and synergetic actions of the two proteins may contribute substantially to protection against V. dahliae infection in cotton plants.

GhCPK33 Negatively Regulates Defense against Verticillium dahliae by Phosphorylating GhOPR3

“…Verticillium wilt is a type of vascular disease caused by the soil-borne fungus Verticillium dahliae, and it is the most destructive disease of cotton (Gossypium hirsutum) production (Gao et al, 2013a;Yang et al, 2015). Unfortunately, there is no Verticillium wilt immune germplasm in the widely planted upland cotton .…”

RNA-seq Transcriptome Response of Flax (Linum usitatissimum L.) to the Pathogenic Fungus Fusarium oxysporum f. sp. lini

“…From 14 transcripts matching MLPs, 11 were consistently repressed (Supplementary Figure S5V). Although the function of these proteins has not been completely elucidated, there is evidence of their regulation through hormone signaling (Ruperti et al, 2002; Yang et al, 2015; Wang et al, 2016), and activation in response to pathogens (Schenk et al, 2000; Kiirika et al, 2014; Yang et al, 2015). However, our results were opposite to these studies and we found only one study were 16 major latex proteins were repressed in response to oxidative stress in Arabidopsis (Stanley Kim et al, 2004).…”

The potato transcription factor StbZIP61 regulates dynamic biosynthesis of salicylic acid in defense against Phytophthora infestans infection

“…Transient expression assays were performed as described by Yang et al (2014). Approximately 1.7 kb upstream of StICS1 was amplified from genomic DNA by PCR and cloned into pGWB435 (Invitrogen) to generate the StICS1 Pro :Luc reporter construct.…”