The Prelimary Studies On Expression Patterns And Function Of MAP Kinase Kinase Gene Family In Oryza Sativa L.

Mitogen-activated protein kinase(MAPK) cascades play a crucial role in plant growth and development as well as biotic and abiotic stress responses.In rice(Oryza sativa),a monocot model and economically important cereal crop,only two MAPKKs were characterized.In this study.We have identified 9 members of the rice MAPKKs family through an EST and cDNA hitting search of rice genome databases.Results of the experiment is as following.1.Upon real time PCR,we analyze the difference of expression of OsMKKs under different organ(leaf,root and flower).The result indicate that OsMKKI,OsMKK3, OsMKK4,OsMKK5,OsMKK6 or OsMKK10-2 confer expression in shoot root and flower, and the expression is varied in root.OsMKK8,OsMKK9 or OsMKK10-1 confer low expression in diferent organ,they expressed mainly in root and flower.2.Upon elicitor inducing with the different signal molecules such as H₂O₂,salicylic acid(SA),abscisic acid(ABA),methyl jasmonic acid(MeJA),Mannitiol,NaCl and cold(4℃) treatment.8 of 90sMKKs genes were found to be induced at the mRNA level during either early,late,or both stages of treatment.The genome-wide expression analysis suggests that:OsMKK1 confers strong expression under the induction of H₂O₂,SA,ABA,MeJA, Mannitiol,NaCl or Cold(4℃)and early expression before 30 minutes.When treated with H₂O₂,SA,Mannitiol,NaCl,the expression of OsMKK1 in the root was earlier and higher than in the shoot.But the expression of OsMKK1 under the induction of ABA,Me-JA is on the contray.OsMKK3 confers complex expression under the induction of H₂O₂,SA,ABA, MeJA,Mannitiol,NaCl or Cold(4℃).OsMKK3 confers strong expression under the induction of Mannitiol,NaCl or Cold(4℃).OsMKK3 confers different expression under the induction of SA,ABA and Me-JA between leaves and roots of,in the early time when treated with SA,the expression rised in the root but declined in the shoot,the expression of ABA and Me-JA in on the contrary.OsMKK3 confers fall expression when treated with H₂O₂.OsMKK4 confers early strong expression under the induction of H₂O₂,MeJA and Mannitiol.The early expression of OsMKK4 treated with ABA,NaC1 and low temperature(4℃) is different between shoot and root,it rised in the root and declined in the shoot OsMKK4 confers early fall expression when treated with SA.OsMKK5 confers early strong expression under the induction of H₂O₂,SA,ABA, Me-JA,Mannitiol and NaCl.It expressed late when treated with H202,and early when treated with ABA and NaCl.When treated with SA and Mannitiol,it expressed early in the root and late in the shoot,it expressed on the contray when treated with Me-JA.When treated with low temperature(4℃),it confers rise expression in the shoot and fall expression in the root.OsMKK6 confers strong expression under the induction of H₂O₂,SA,ABA,MeJA, Mannitiol,NaCl or Cold(4℃).It expressed late when treated with H₂O₂ and early when treated with SA,NaCl or Cold(4℃).It expressed different between shoot and root when treated with the ABA or Mannitiol.OsMKK8 and OsMKK9 confers no expression under the different inductionOsMKK10-1 confers strong expression under the induction of H₂O₂,SA,NaCl and low temperature,It expressed late when treated with H₂O₂ and early when treated with SA, NaCl or low temperature(4℃).OsMKK10-2 confers strong expression under the induction of H₂O₂,it expressed early in the root and late in the shoot.It confers decline expression under the induction of low temperature(4℃).It expressed different between shoot and root when early treated with SA,ABA,Me-JA,Mannitiol and NaCl,its expression rised in the shoot and falled in the root when treated with ABA or Me-JA,its expression rised in the root and failed in the shoot when treated with SA,Mannitiol and NaCl.3.One of rice MAPKKs which known as OsMKK3 was cloned and analyzed by gene overexpression and silencing ways.