Lipid Profiling Leymus chinensis Root Insensitive to Ca Deprivation

Abstract

Abstract Background Leymus chinensis (L. chinensis) is a perennial native forage grass widely distributed in the steppe of Inner Monoglia as the dominant species. Calcium (Ca) as an essential mineral element important for plant’s adaptation to its growth environment. Results In this study, significance of Ca for L. chinensis growth and membrane stability was investigated and compared with that for Arabidopsis. Previously it was found that Ca deprivation strongly inhibited Arabidopsis seedling growth, disrupted the plasma membrane stability and selectivity, accompanied with increasing fluid-phase based endocytosis and contents of all major membrane lipids. In contrast, L. chinensis seedlings growth and root endocytosis activity were not affected by Ca deprivation. The plasma membrane maintained high selectivity. The PC:PE ratio, an indicator of the membrane stability, is five times higher in the L. chinensis than the Arabidopsis. In addition, Ca deprivation did not affect contents of all major lipid types in L. chinensis. Ca deprivation increased the MDA contents and decreased the SOD activity in L. chinensis, which were opposite with Arabidopsis. L. chinensis roots have higher contents of PC, PI, MDGD, PG, CL, DGDG, LPC, but less of PE, DAG, TAG, PS, LPA, LPE, LPS than those in Arabidopsis roots. Moreover, 31 unique lipid species were found in L. chinensis, and 66 unique in Arabidopsis. Conclusions This study revealed that L. chinensis root has unique membrane lipid composition without much Ca dependence, which might be accounted for the plant’s ability to distribute wide-range of natural environment.