Lipo-chitooligosaccharide and thuricin 17 act as plant growth promoters and alleviate drought stress in Arabidopsis thaliana.
作者: Sowmyalakshmi Subramanian ; Erika Mitkus ; Alfred Souleimanov ; Donald L Smith
Lipo-chito-oligosaccharide (LCO-from Bradyrhizobium japonicum) and thuricin 17 (Th17-from Bacillus thuringiensis) are bacterial signal compounds from the rhizosphere of soybean that have been shown to enhance plant growth in a range of legumes and non-legumes. In this study, an attempt to quantify phytohormones involved in the initial hours after exposure of Arabidopsis thaliana to these compounds was conducted using UPLC-ESI-MS/MS. A petri-plate assay was conducted to screen for drought stress tolerance to PEG 8000 infusion and plant growth was studied 21-days post-stress. Arabidopsis thaliana plants grown in trays with drought stress imposed by water withhold were used for free proline determination, elemental analysis, and untargeted proteomics using LC-MS/MS studies. At 24 h post-exposure to the signal compounds under optimal growth conditions, Arabidopsis thaliana rosettes varied in their responses to the two signals. While LCO-treated rosettes showed a decrease in total IAA, cytokinins, gibberellins, and jasmonic acid, increases in ABA and SA was very clear. Th17-treated rosettes, on the other hand, showed an increase in IAA and SA. Both treatments resulted in decreased JA levels. Under severe drought stress imposed by PEG 8000 infusion, LCO and Th17 treatments were found to significantly increase fresh and dry weight over drought-stressed control plates, indicating that the presence of the signaling compounds decreased the negative effects experienced by the plants. Free proline content increased in LCO- and Th17-treated plants after water-withhold drought stress. Elemental analysis showed a significant increase in carbon percentage at the lower concentration of Th17. Untargeted proteomics revealed changes in the levels of drought-specific ribosomal proteins, glutathione S-transferase, late embryogenesis proteins, vegetative storage proteins 1 and 2, thaumatin-like proteins, and those related to chloroplast and carbon metabolism. The roles of some of these significantly affected proteins detected under drought stress are discussed.
2022-01-01·Frontiers in plant science
The stimulatory effect of Thuricin 17, a PGPR-produced bacteriocin, on canola (Brassica, napus L.) germination and vegetative growth under stressful temperatures.
作者: Mahtab Nazari ; Iraj Yaghoubian ; Donald L Smith
Exposure to unfavorable conditions is becoming more frequent for plants due to climate change, posing a threat to global food security. Stressful temperature, as a major environmental factor, adversely affects plant growth and development, and consequently agricultural production. Hence, development of sustainable approaches to assist plants in dealing with environmental challenges is of great importance. Compatible plant-microbe interactions and signal molecules produced within these interactions, such as bacteriocins, could be promising approaches to managing the impacts of abiotic stresses on crops. Although the use of bacteriocins in food preservation is widespread, only a small number of studies have examined their potential in agriculture. Therefore, we studied the effect of three concentrations of Thuricin17 (Th17), a plant growth-promoting rhizobacterial signal molecule produced by Bacillus thuringiensis, on germination and vegetative growth of canola (Brassica napus L.) under stressful temperatures. Canola responded positively to treatment with the bacterial signal molecule under stressful temperatures. Treatment with 10 -9 M Th17 (Thu2) was found to significantly enhance germination rate, seed vigor index, radical and shoot length and seedling fresh weight under low temperature, and this treatment reduced germination time which would be an asset for higher latitude, short growing season climates. Likewise, Thu2 was able to alleviate the adverse effects of high temperature on germination and seed vigor. Regarding vegetative growth, interestingly, moderate high temperature with the assistance of the compound caused more growth and development than the control conditions. Conversely, low temperature negatively affected plant growth, and Th17 did not help overcome this effect. Specifically, the application of 10 -9 (Thu2) and 10 -11 M (Thu3) Th17 had a stimulatory effect on height, leaf area and biomass accumulation under above-optimal conditions, which could be attributed to modifications of below-ground structures, including root length, root surface, root volume and root diameter, as well as photosynthetic rate. However, no significant effects were observed under optimal conditions for almost all measured variables. Therefore, the signal compound tends to have a stimulatory impact at stressful temperatures but not under optimal conditions. Hence, supplementation with Th17 would have the potential as a plant growth promoter under stressed circumstances.
2020-06-01·Journal of pharmaceutical sciences3区 · 医学
Delivery of TSPAN1 siRNA by Novel Th17 Targeted Cationic Liposomes for Gastric Cancer Intervention.
3区 · 医学
作者: Zhengmao Lu ; Tao Pang ; Xiaoyi Yin ; Hangtian Cui ; Guoen Fang ; Xuchao Xue ; Tianhang Luo
Several studies focus on the relationship between immune cells in the tumor microenvironment and tumor cells. Th17 cells, a naïve CD4+ T cell subtype, secrete IL-17 cytokines that further the progression and metastasis of tumors, such as gastric cancer, which is a leading cause of cancer-related death worldwide. Moreover, previous studies have demonstrated that the polarization ratio of CD4+ T cells to Th17 cells is closely related to the Tetraspanin 1 (TSPAN1) protein. Therefore, in this study, we designed a novel Th17 antibody-modified liposome polycation-DNA complex (LPD) encapsulated with TSPAN1 small interfering RNA (siRNA) (Th17-LPDT), to decrease the polarization of CD4+ T cells, and thereby inhibit the development of gastric cancer. Our in vitro results demonstrated the decrease in CD4+ T cells polarization to Th17 cells follwing Th17-LPDT treatment. Furthermore, in vivo data proved that Th17-LPDT treatment significantly inhibits the formation of gastric tumors. We believe that Th17-LPDT is a promising targeted nanoparticle drug for the clinical treatment of gastric cancer and this study provides a new strategy for tumor intervention.