Elements perturbation in Arabidopsis thaliana under low temperature stress by ICP-MS based subcellular metallomics

Abstract

The mechanism of how plants response to low temperature stress is very important for resistance improvement and yield increase. As far as we know, no research has been reported on high coverage of elements perturbation of plants under low temperature stress by metallomics at subcellular level until now. In this study, a subcellular metallomics analytical method of Arabidopsis thaliana based on differential centrifugation-microwave digestion coupled with inductively coupled plasma mass spectrometry was developed. The correlation coefficients R2 of 69 elements were all above 0.9928 in the corresponding linear ranges of 3 orders of magnitude. The limits of detections (LODs) ranged from 0.000005 to 1.535 µg g-1, and limits of quantifications (LOQs) ranged from 0.00002 to 5.118 µg g-1. Forty elements in 5 subcellular fractions with 66.8% of accumulated percentage of relative standard deviations (RSDs) below 30% could be reasonably determined. The method accuracy was validated by certified reference material (CRM) (GBW10028). Under low temperature stress, the absolute contents of 51 subcellular fractions of 26 elements changed significantly with fold changes ranging from 0.18~3.16 between the low temperature group and the control one. Three main trends of significant elemental perturbation in subcellular components under cold stress were found: the contents of some elements (Co, Fe, Rb and W) increased in chloroplasts; the contents of elements (Eu, Nb, Th, Ti, Dy, Lu, Y, Cs, Si and Yb) increased in cell wall component; the contents of elements (Ba, K, Mg, Mn, P, Ca, Sr Mo and Zn) decreased in the nuclear component but increased in the chloroplast and mitochondrial components. The method was proved accurate, stable and reliable enough with wide elemental coverage, high throughput and high sensitivity, and it could be a good technical reference for the obtaining of multi-elemental characteristics at subcellular level in plants.