The Research Of The Phosphorus Transport Protein Induced By AMF Specificity AsPT1and AsPT4Transport Receptor Function

Phosphorus is one of the three essential major nutrition elements for plant growth, and soil deficiency has become a major factor restricting China’s crop yield. The symbiotic, arbuscular mycorrhizal fungi(AMF) and host plants formed, shaping a network by mycelium in the soil to absorb soil phosphorus broader, improves plant phosphorus uptake rate. The phosphorus between mycorrhizal fungi and host plant uptake and transport mainly by phosphate transporter protein which is located in the plants and fungi symbiotic interface. However, at present whether phosphate transporter protein can participate in phosphorus signal transduction by forming transporter receptors is also poorly understood.The topic, using AM fungi Glomus intraradices and Astragalua sinicus L. as materials, choose two specific expression phosphate transporter genes induced by mycorrhizal fungi from six AsPhtl, the phosphate transporter gene-AsPTl and AsPT4genes, which is separated from our laboratory a family. Using molecular biology, biochemistry and physiology and other methods, we have deeply studied the phosphate transporter protein AsPTl and AsPT4interacting and identifying outside Pi in the symbiosis with mycorrhizal and regulating plant root growth and development of plant root hormone transporter receptor function. Which providing new molecular evidence in fully clarifying the phosphate transporter protein AsPTl and AsPT4how to adjust the AM symbiosis and plants in symbiosis with AMF and non-symbiotic growth, especially abruscular growth and development and improvement of host nutrition.1. AsPTl and AsPT4proteins play an important role in the growth and development of mycorrhizal.they not only regulate the formation of symbiotic further regulate arbuscular development. Once decreasing of AsPTl and AsPT4genes expression, infection intensity and arbuscular abundance in the symbiont of AMF and host would decrease significantly, leading to arbuscular dysplasia, early degradation and even death.2. AsPTl and AsPT4play a major role in the Astragalua sinicus L. symbiotic and non-symbiotic Pi transport pathway. And AsPTl transporter receptor function may have, in addition to transport phosphorus, but also can identify the Pi signal, adjust the symbiotic interface of phosphate homeostasis by Pi signaling pathways. In addition, AsPTl and AsPT4genes in addition to being induced expression in mycorrhizal symbiosis time, but also expressed in the apical non-symbiotic plants, and decreased expression of symbiotic plants in root tips.3. The silence expression of AsPTl and AsPT4genes under different phosphorus concentration conditions have affected the PKA signaling pathway in plants, resulting in the changes of trehalose activity, which we can speculate that AsPTl and AsPT4involved in the process of Pi signal transduction.4. AsPTl and AsPT4regulate the developmental status of non-symbiotic plant roots, especially in lateral root development. The silence expression of AsPT1and AsPT4genes have affected the plant hormone levels of Astragalua sinicus L. transformation root, especially IAA-asp bound to aspartate. In addition, exogenous hormones can influence AsPTl and AsPT4gene expression. It can be speculated, AsPTl and AsPT4transporter protein may be a hormone receptor, which can regulate growth and development of plant roots through transporting and regulating hormones in plants.In short, AsPT1and AsPT4phosphate transporter protein plays a large role in the AMF fungal symbiosis with the host plant, regulating the growth of arbuscular mycorrhizal structures. Moreover, AsPTl and AsPT4may be a class of very complex multi-functional of transporter receptor, which is not only involved in the signaling pathway and also involved in the abiotic stress signaling processes and plant hormone signaling process.