Characteristics And Functional Analysis Of The ENA P-Type ATpase Gene MaENA1in Metarhizium Acridum

Entomopathogenic fungi are naturally widespread in most terrestrial ecosystems.They have a world-wide distribution from the arctic to the tropics and colonize animpressive array of environments including forests, savannahs, swamps, coastal zonesand deserts. They have a wide range of applications with common characteristics interms of natural pest control, they also have considerable application potential anddevelopment prospects. In the past20years, great progresses have been made onentomopathogenic fungi, also made the insect pathogenic fungi became an importantpart of fungal biocontrol agents. When applied as biocontrol agent in field, conidia ofentomopathogenic fungi are exposed to high temperature and UV radiation, thetemperatures fluctuate in habitats of pest insect, and pests like locusts themselves couldalso employ behavioral fever to counter fungal infection, tolerance to heat stress isimportant for the fungal pathogens. Thus, entomopathogenic fungi are exposed to avariety of environments with osmotic stress, heat stress, UV radiation and other stresses.So we need to study and improve thess fungal biocontrol agents from all aspects.Metarhizium as environmentally harmful pesticides, compared with chemicalinsecticides have a larger advantage, at the same time they can also be used as a modelsystem for the study of insect-fungus interactions and genetic resources asbiotechnology.Metarhizium acridum, its capacity for stress tolerance is closely associated with itsproduction and application. A number of studies have found that ENA ATPase canproduce a high osmotic stress response and associated with some stress relatedpathways, i.e. MAPK pathways and the branches HOG pathway, Ca2+pathway, TORpathway. In these pathways, there are a balance between the node genes and ENA1.However, most of these studies were in yeast, human pathogens, bryophytes, we foundno studies and reports in insect pathogenic fungi. To elucidate the role of ENA ATPasein entomopathogenic fungi and explore the mechanisms involved, the ENA ATPasegene of M. acridum, MaENA1, was functionally studied by the construction of disruptedtransformant and complementary transformant, and the differential genes and pathwaysbetween disrupted transformant and wild strain were analyzed by Digital GeneExpression Profiling.The main results are as follows: ①M. acridum MaENA1does not affect the normal growth, germination rate,sporulation and virulence. MaENA1does not affect cell wall integrity, antioxidantcapacity, K+, the non ion tolerance to osmotic pressure②MaENA1is specifically sensitive to Na+stress and at the transcriptional level,under the presence of Na+, its expression was significantly upregulated.③MaENA1regulates the thermo-and UV-tolerances of conidia in M. acridum.④Digital Gene Expression analysis. Our transcriptome analysis revealed possibleinvolvements of many factors and signaling pathways in multi-stress responses,including various MAPK cascades, cAMP pathway, RIM101pathway, cytochromeP450superfamily, oxidoreductase genes, ion binding genes, DNA repair genes, othergens like MFS transporters (transporters of the major facilitator superfamily), ABCtransporters (ATP-binding cassette transporters), Cu/Zn-SOD because thermo-and UV-tolerances were reducing in ΔMaENA1.