Molecular Determinants and Regulatory Mechanisms of Nutrient Exchange Between Plant and AMF

Most of the land plant species establish mutualistic associations with arbuscular mycorrhizal fungi (AMF). This is an evolutionary conserved symbiotic relationship where mycorrhizal partner provides nutrients [especially nitrogen (N), phosphorus (P)] in exchange of carbon compounds from the host plant. Various plant genes, hormones and receptors regulate this association at different levels. The key signaling molecules involved in AM-host symbiosis are plant derived hormones i.e., strigolactones (SLs) and fungal derived Myc factors including, lipo chito oligosaccaharides. In addition, successful establishment of mycorrhizal symbiosis also requires regulation of various transcripts induced by mutual exchange of signals. After the process of symbiotic development, the genes responsible for nutrient uptake and translocation are upregulated, in order to improve the supply of nutrients to the host plants, especially under nutrient deficient conditions. However, till date, an updated information on the mechanism underlying the process of signaling, molecular cascade, development of mycorrhizal structures and nutrient exchange between host and mycorrhiza is lacking. Therefore, present review tries to bridge the gaps underlying various molecular dialogues during mycorrhizal symbiosis and nutrient exchange between host and AM fungal interface.