Ectopic expression of a cyanobacterial flavodoxin in creeping bentgrass impacts plant development and confers broad abiotic stress tolerance

Abstract

SummaryFlavodoxin (Fld) plays a pivotal role in photosynthetic microorganisms as an alternative electron carrier flavoprotein under adverse environmental conditions. Cyanobacterial Fld has been demonstrated to be able to substitute ferredoxin of higher plants in most electron transfer processes under stressful conditions. We have explored the potential of Fld for use in improving plant stress response in creeping bentgrass (Agrostis stolonifera L.). Overexpression of Fld altered plant growth and development. Most significantly, transgenic plants exhibited drastically enhanced performance under oxidative, drought and heat stress as well as nitrogen (N) starvation, which was associated with higher water retention and cell membrane integrity than wild‐type controls, modified expression of heat‐shock protein genes, production of more reduced thioredoxin, elevated N accumulation and total chlorophyll content as well as up‐regulated expression of nitrite reductase and N transporter genes. Further analysis revealed that the expression of other stress‐related genes was also impacted in Fld‐expressing transgenics. Our data establish a key role of Fld in modulating plant growth and development and plant response to multiple sources of adverse environmental conditions in crop species. This demonstrates the feasibility of manipulating Fld in crop species for genetic engineering of plant stress tolerance.

Transgenic creeping bentgrass overexpressing Osa‐miR393a exhibits altered plant development and improved multiple stress tolerance

“…For example, the accumulation of a small HSP, HSP25, was positively correlated with the thermotolerance in creeping bentgrass (Park et al ., ). To investigate the mechanism of miR393‐mediated plant response to heat stress at molecular level, we analysed expression of AsHSP17.0 and AsHSP26.7a , the two small HSP genes responding to high temperature in wild‐type and transgenic plants (Li et al ., , ; Sun et al ., ). Quantitative RT–PCR shows that AsHSP17.0 and AsHSP26.7a are induced during heat stress in both transgenic plants and controls, but the expression levels are higher in transgenics than in wild‐type controls (Figure f,g).…”

A Specific Single Nucleotide Polymorphism in the ATP Synthase Gene Significantly Improves Environmental Stress Tolerance of Synechococcus elongatus PCC 7942

“…fully used for improving the stress tolerances of higher plants (4,5). In recent years, cyanobacterial cells have been genetically engineered to produce many chemicals and fuels directly from carbon dioxide and solar energy by modifying natural metabolic pathways and installing heterologous synthetic pathways (6).…”

Transcriptional and Metabolic Profiling of Potato Plants Expressing a Plastid-Targeted Electron Shuttle Reveal Modulation of Genes Associated to Drought Tolerance by Chloroplast Redox Poise

“…Long before the advent of terrestrial plants, the Fld gene disappeared during the evolutionary transition of the green algal lineage from the open ocean to freshwater, correlating with changes in iron bioavailability across habitats (low in the ocean, high in freshwater) that impact Fd levels [ 18 ]. However, introduction of a plastid-targeted Fld in various plant species improved delivery of reducing equivalents to productive pathways of the chloroplast, which in turn restricted plastid ROS production and increased tolerance to drought and other stresses [ 15 , 16 , 19 , 20 , 21 , 22 ].…”