Transgenic RXLR Effector PITG_15718.2 Suppresses Immunity and Reduces Vegetative Growth in Potato

Abstract

Phytophthora infestans causes the severe late blight disease of potato. During its infection process, P. infestans delivers hundreds of RXLR (Arg-x-Leu-Arg, x behalf of any one amino acid) effectors to manipulate processes in its hosts, creating a suitable environment for invasion and proliferation. Several effectors interact with host proteins to suppress host immunity and inhibit plant growth. However, little is known about how P. infestans regulates the host transcriptome. Here, we identified an RXLR effector, PITG_15718.2, which is upregulated and maintains a high expression level throughout the infection. Stable transgenic potato (Solanum tuberosum) lines expressing PITG_15718.2 show enhanced leaf colonization by P. infestans and reduced vegetative growth. We further investigated the transcriptional changes between three PITG_15718.2 transgenic lines and the wild type Désirée by using RNA sequencing (RNA-Seq). Compared with Désirée, 190 differentially expressed genes (DEGs) were identified, including 158 upregulated genes and 32 downregulated genes in PITG_15718.2 transgenic lines. Eight upregulated and nine downregulated DEGs were validated by real-time RT-PCR, which showed a high correlation with the expression level identified by RNA-Seq. These DEGs will help to explore the mechanism of PITG_15718.2-mediated immunity and growth inhibition in the future.

Copper ions suppress abscisic acid biosynthesis to enhance defence against Phytophthora infestans in potato

“…Droplets (10 µl) were pipetted onto the surface of detached leaves, placed in sealed boxes with moist tissue to maintain humidity, and kept in weak light. Lesions were measured 3–5 days post‐inoculation (dpi) and scored as described previously (Wang et al , ). Disease indexes were analysed with about 30 leaves from 10 potato plants for each treatment.…”

“…The biomass level analysis was performed as described by Wang et al (). The leaves were harvested at 3–5 dpi and total DNA was extracted with cetyltrimethylammonium bromide solution.…”

A nonspecific lipid transfer protein, StLTP10, mediates resistance to Phytophthora infestans in potato

“…For drop inoculation, the surfaces of detached leaves were inoculated with 15 μl of P. infestans zoospore suspension and then placed at 18°C in sealed boxes with 100% RH environment, and kept in weak light. The diameters of lesions were measured at 5 dpi and scored as described by Wang et al (2019). The biomass of P. infestans was also analysed.…”

Genome-Wide Identification and Characterization of Potato Long Non-coding RNAs Associated With Phytophthora infestans Resistance

“…The P. infestans isolate HLJ, a strongly pathogenic oomycete, was conserved at the State Key Laboratory of Shandong Agricultural University, Tai’an, Shandong, China ( Wang et al, 2019 ). P. infestans HLJ was grown in Petri dishes with Rye A for 2 weeks at 18°C.…”