Genome-wide identification and characterization of genes involved in phosphate recycling and transport
Student name: Ms Radhika Mehtani
Guide: Dr Pallavi Somvanshi
Year of completion: 2017
Host Organisation: National Institute of Plant Genome Research, New Delhi
Supervisor (Host Organisation): Dr Jitender Giri
Abstract: Phosphorus is a crucial nutrients required for plant’s optimal growth. It makes P unavailable to plants by forming complexes with calcium salts, aluminium or iron oxide which plants can utilize in fully oxidized state, H2PO4- or HPO42- . To overcome this nutritional stress, plants have evolved their mechanism which includes root system architecture change; biochemical changes such as release of organic acid, anthocyanin accumulation; increase phosphate transporters expression and production of enzymes like acid phosphatases, ribonucleases and exonucleases.
Purple acid phosphatases (PAP) are the acid phosphatases involved in release of inorganic phosphorus (Pi) from orthophosphate monoesters that are present in rhizosphere and their recycling within the plant. PAPs are stated to be released under low P condition, thereby indicating their role in disabling P famishment. PAPs in Setaria itlaica have been identified, possessing their characteristics including metallophos domain and conserved motifs. They show more closeness with Oryza sativa PAPs rather than Arabidopsis thaliana PAPs. Various attributes involving phonotypical and biochemical assays have been studied for PAPs under both P sufficient and P deficient growth media.
SPDT (SULTR-like phosphorus distribution transporter) gene, in involved in P accumulation in the grain, finally storing it in the form of indigestible phytate. This indigestible phytate causes waterways pollution and also lowers the availability of zinc and iron to the grains by forming complexes. In this study, we have identified SPDT gene in various plant species and studied their characteristics in terms of domain architecture, phylogenetic relationships among themselves and their in-silico expression showing maximum expression in shoot tissue and flower buds. The gene of approximately 2kb size has also been amplified.
KEYWORDS: PAPs, SPDT, Phosphate, Phytate, Transporters
