Expression And Regulation Analysis Of Maize Plasma Membrane Intrinsic Protein Coding Gene ZmPIP1;1in Arabidopsis Under Stress Conditions

Maize is a major crop around the world.Similarily,as the most important crop in China's agriculture,maize has made great contributions to food production,animal husbandry and agricultural economy.Therefore,it's the agricultural researchers' duty and goal to increase the yield per unit,total yield and breeding quality.Aquaporins have special function in response to abiotic stress in plant.Molecular mechanism of aquaporins tolerance to stress should be further studied in maize,and it's significant for breeding and improvement in yeild and quality of maize.This research identified a plasma membrane intrinsic protein ZmPIP1;1 from maize and analysed its function in drought and salt tolerance of transgenic Arabidopsis plants.The main results are as follows:1.ZmPIP1;1 contains six putative transmembrane a-helices and a conserved sequence.Subcellular localization experiment indicated that the gene ZmPIP1;1 was localized on the plasma membrane and endoplasmic reticulum..2.In maize,ZmPIP1;1 was the highest expressed PIPs and was highly abundant in tassel,ear,leaf,stem and root whereas it was lowly expressed in embryo and endosperm.3.ZmPIP1;1 was induced with 10% PEG and 100 mM NaCl both in maize roots and shoots in different time,we thought that ZmPIP1;1 may be involved with maize osmotic and salt stress tolerance.4.Primary root length of ZmPIP1;1-Oe Arabidopsis plants in drought and salt stress and growth of ZmPIP1;1-Oe Arabidopsis plants under drought treatment in soil culture indicated that overexpression of ZmPIP1;1 improved Arabidopsis plants' tolerance to drought and salt stress.5.Induced expression of stress responsive genes in ZmPIP1;1-Oe Arabidopsis plants under drought and salt stress suggested that ZmPIP1;1 was rapidly induced by drought and salt stress,and it regulated a number of genes involved in stress response.6.Decreased contents of ROS and increased activities of ROS scavenging enzymes in ZmPIP1;1-Oe Arabidopsis plants under drought and salt stress showed that overexpression of ZmPIP1;1 might improved regulation of the modulation of cellular osmoprotection and cellular redox and ROS homeostasis,and this might result from increased activities of ROS scavenging enzymes.In conclusion,we found that ZmPIP1;1 was rapidly induced upon under water stress,and it could improve plants' tolerance to drought and salt stress when be overexpressed in Arabidopsis not only by up-regulation of stress responsive genes but also by increasing of ROS scavenging enzymes activities.