Micro-XRF Spectrometers

Analyzing Mineral Levels and Distribution in Plants

Bruker’s M4 TORNADO micro-XRF spectrometer plays an important role in researching the role of alternative splicing (AS) mechanisms which appear to function in plant responses to environmental stress. Research scientists use the M4 TORNADO to help understand adaptive strategies used by plants to withstand a deficiency or excess of a specific mineral nutrient. This in turn helps determine ways to breed crops with higher mineral nutrient-use efficiency.

Research scientists at Nanjing Agricultural University, Nanjing, China and La Trobe University, Melbourne, Australia collaborated to analyze the role of serine/arginine-rich (SR) proteins which regulate AS mechanisms. They generated mutants of SR protein genes of the rice (Oryza sativa) family to determine if they had a regulatory role in mineral uptake and mobilization in rice shoots. Roots grown in either the presence or the absence of phosphorus (P) were of particular interest.

Distribution of phosphorus in selected leaves was analyzed with micro-XRF scanning at a high resolution using the M4 TORNADO to confirm that necrotic spots in the leaves only arise under excessive accumulation of phosphorus. This work helped prove that the targets of AS are highly nutrient-specific. It also verified the role of AS in mineral nutrition by characterizing mutants in genes encoding SR proteins that function in AS. Researchers identified proteins as mineral nutrient regulators in rice, showing that three SR protein-encoding genes regulate the phosphorus uptake and remobilization between leaves and shoots of rice, demonstrating that AS has a key role in regulating the mineral nutrient homeostasis in rice.