Biological Function Analysis Of A Novel Mutant Zinc Finger Protein Gene In Magnaporthe Oryzae

Rice is one of the most important food crop, about half of the world’s population torice as the main food. The Magnaporthe oryzae （M. oryzae） is the causative agent ofrice blast disease and presents a significant threat to the safety of worldwide riceproduction. Breeding reasonably, planting resistant varieties and using of chemicalpesticides are the main measures to control the rice blast presently. However, When anew disease-resistant varieties planted widely3-5years, the new drug-resistant andpathogenic groups emerge, resulting in the loss of resistance of these varieties, easilyleading to the outbreak and spread of the rice blast for their single disease-resistance,the variability of the pathogen, as well as the genetic diversity the rice blast fungusphysiological race, The long-term use of the single chemical pesticides not only makesthe rice blast fungus resistance of ordinary chemical pesticides continue to improve, butalso result in the climbing of the prevention cost in company with the worsening of theenvironment. Therefore, rice production is to be badly in need of the new controlstrategy for environmental protection and safety.Prevention of the rice blast is always the problem to rice production cannot beignored. To understand mechanisms of the growth development and pathogenicmolecular regulation process about the rice blast fungus is an important prerequisite tocontrol the disease. T-DNA insertional mutagenesis is an effective way to identify riceblast fungus genes related. This article founds a novel pathogenic gene MoZF1in M.oryzae using agrobacterium tumefaciens mediated transformation （ATMT）. Byknockout and genetic complementation, we studied the function of MoZF1about the regulations of the growth, conidia formation, antirecession force and pathogenicity of M.oryzae.Our research group identified a T-DNA mutant （T-23） from the ATMT mutantlibrary, which displayed reduced pathogenicity and conidiation and so on. The insertionlocus was identified using thermal asymmetric interlaced polymerase chain reaction（TAIL-PCR）. Sequences of the PCR products were matched to MGG₀8239.6of M.oryzae, one hypothetical protein. The predicted ORF of this gene was1780bp long,encoding501amino acids, and there was three extrons and two introns on.Primers were designed based on the complete genome sequence of M. oryzae toconstruct the targeted gene disruption vector and fusion expression vector （i.e., thecomplementary expression vector）. Finally, we got the targeted gene disruptiontransformants （ΔMozf1-4） and complementary transformants （ΔMozf1/ZF1-5） usingATMT method into M. oryzae. We evaluated the characteristics such as the myceliummorphology, conidiation and other biological ones. Our studies display that the targetedgene disruption transformants have some defects in mycelium morphology, conidiationand pathogenicity, but complementary transformants has a great consistency with thewild-type strains. Our results suggest that Mozf1serves as a pathogenicity factor thatregulate these characteristics.After the above studies suggest that the Mozf1gene plays an important role in theregulation of the mycelial growth, conidia formation and pathogenicity in M. oryzae.