Project description:Tomato plants are commonly attacked by herbivorous mites, including by generalist Tetranychus urticae and specialists Tetranychus evansi and Aculops lycopersici. Mite feeding induces plant defense responses that reduce mite performance. However, via poorly understood mechanisms, T. evansi and A. lycopersici suppress plant defenses and, consequently, maintain a high performance on tomato. Accordingly, on a shared host, non-adapted T. urticae can be facilitated by either of the specialist mites, likely via the suppression of plant defenses. To better understand defense suppression and indirect plant-mediated interactions between herbivorous mites, we used microarrays to analyze transcriptomic changes in tomato after attack by either a single mite species (T. urticae, T. evansi, A. lycopersici) or two species simultaneously (T. urticae plus T. evansi or T. urticae plus A. lycopersici). Additionally, we assessed mite-induced changes in defense-associated phytohormones using LC-MS/MS. Compared to non-infested controls, jasmonates (JAs) and salicylate (SA) accumulated to higher amounts upon all mite-infestation treatments, but lowest increases were detected after single infestations with defense-suppressors. Strikingly, whereas 8 to 10% of tomato genes was differentially expressed upon single infestations with T. urticae or A. lycopersici, only 0.1% was altered in T. evansi-infested plants. Transcriptome analysis of dual-infested leaves revealed that T. evansi dampened T. urticae-triggered host responses on a genome-wide scale, while A. lycopersici primarily suppressed T. urticae-induced JA defenses. Our results provide valuable new insights into the mechanisms underlying host defense suppression and the plant-mediated facilitation of competing herbivores.
Project description:Transcriptome analysis reveals the response mechanism of Frl-mediated resistance to Fusarium oxysporum f. sp. radicis-lycopersici (FORL) infection in tomato
Project description:RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. IM-862 may stop the growth of colorectal cancer by stopping blood flow to the tumor. It is not yet known if chemotherapy is more effective with or without IM-862 in treating colorectal cancer.
PURPOSE: Randomized phase II trial to study the effectiveness of chemotherapy plus IM-862 in treating patients who have metastatic colorectal cancer.
Project description:To study whether there are differences in chromatin-mediated regulation between and within chromosomes in Fusarium oxysporum f. sp. lycopersici 4287 (FGSC9935), we determined the distribution of histone marks associated with euchromatin (H3K4me2) and facultative heterochromatin (H3K27me3) in vitro. We then determined whether these differences correlate with differences in dispensability and sequence divergence and gene expression.
