GhWRKY70D13 Regulates Resistance to Verticillium dahliae in Cotton Through the Ethylene and Jasmonic Acid Signaling Pathways

Abstract

Verticillium wilt caused by Verticillium dahliae is a destructive cotton disease causing severe yield and quality losses worldwide. WRKY transcription factors play important roles in plant defense against pathogen infection. However, little has been reported on the functions of WRKYs in cotton's resistance to V. dahliae. Here, we identified 5, 5, and 10 WRKY70 genes in Gossypium arboreum, Gossypium raimondii, and Gossypium hirsutum, respectively, and investigated the expression profiles of all GhWRKY70 genes in various cotton tissues and in response to hormone treatment or V. dahliae infection. Reverse transcription-quantitative PCR analysis showed that GhWRKY70D13 was expressed higher in roots and stems than in other tissues, and up-regulated after V. dahliae inoculation. Knock-down of GhWRKY70D13 improved resistance to V. dahliae in both resistant and susceptible cotton cultivars. Comparative analysis of transcriptomes generated from wild-type and stable RNAi (RNA interference) plant with down-regulated GhWRKY70D13 showed that genes involved in ethylene (ET) and jasmonic acid (JA) biosynthesis and signaling were significantly upregulated in the GhWRKY70D13 RNAi plants. Consistently, the contents of 1-aminocyclopropane-1-carboxylic (ACC), JA, and JA-isoleucine levels were significantly higher in the GhWRKY70D13 RNAi plants than in wild-type. Following V. dahliae infection, the levels of ACC and JA decreased in the GhWRKY70D13 RNAi plants but still significantly higher (for ACC) than that in wild-type or at the same level (for JA) as in non-infected wild-type plants. Collectively, our results suggested that GhWRKY70D13 negatively regulates cotton's resistance to V. dahliae mainly through its effect on ET and JA biosynthesis and signaling pathways.

The Cotton BEL1-Like Transcription Factor GhBLH7-D06 Negatively Regulates the Defense Response against Verticillium dahliae

“…Moreover, phytohormone crosstalk networks play important roles during plant abiotic and biotic stress responses [ 26 ]. For example, the transcription factor WRKY70, a node of convergence for SA- and JA-mediated signals for plant defense, has been shown to also be a negative regulator during the beginning of ABA-controlled stomatal closure [ 27 , 28 ]. GhATAF1, a NAC transcription factor, confers abiotic and biotic stress responses by regulating phytohormonal signaling networks [ 29 ].…”

Genome-Wide Analysis of Ribosomal Protein GhRPS6 and Its Role in Cotton Verticillium Wilt Resistance

“…Breeding disease-resistant varieties is one of the most economical and effective control measures [4]. In recent years, more and more diseaseresistant genes have been reported, such as the G. hirsutum TIR-NBS-LRR gene GhDSC1, which mediates resistance against Verticillium wilt [11], while heterologous expression of the cotton NBS-LRR gene GbaNA1 enhances Verticillium wilt resistance in A. thaliana [39], GhWRKY70D13 regulates resistance to V. dahliae in cotton through the ethylene and Jasmonic acid signaling pathways [2], GbMPK3 overexpression increases cotton sensitivity to V. dahliae by regulating Salicylic acid signaling [1], HyPRP1 performs a role in negatively regulating cotton resistance to V. dahliae via the thickening of cell walls and ROS accumulation [14], and an ethylene response-related factor, GbERF1-like, from G. barbadense improves resistance to V. dahliae via activating lignin synthesis [17]. The study of these genes has given people a deeper understanding of the molecular basis of resistance to V. dahliae in cotton, but the complexity of tetraploid cotton genome has hindered the cultivation of disease-resistant varieties.…”

“…Cotton is one of the most important cash crops in the world and can be used as an important raw material for the textile, chemical, pharmaceutical, and national defense industries [ 1 ]. The soil-borne fungus Verticillium dahliae is one of the most destructive fungi in the world’s cotton growing areas [ 2 ]. The fungus infects over 200 dicotyledon plant species and live in soil as a dormant structure called microsclerotia for many years.…”

Identification of the Group III WRKY Subfamily and the Functional Analysis of GhWRKY53 in Gossypium hirsutum L.

“…The release of the cotton genome sequence and the establishment of the cotton functional genome database CottonFGD provide a suitable research basis for identifying and analyzing G. hirsutum L. WRKY members. Several researchers had identified and analyzed cotton WRKY family genes in recent years and cloned and identified some essential genes [ 42 , 46 , 47 , 48 , 49 , 50 ]. However, there were few reports on the role of the WRKY gene in cotton fiber development.…”