A shotgun proteomic approach reveals protein expression in morphological changes and programmed cell death in Mimosa pigra seedlings after treatment with coumarins

Mimosa pigra L. (Fabaceae), commonly known as giant mimosa, is one of the major invasive species, constituting a serious threat to agricultural crops and other plants in the biodiversity. With this study, we aimed to investigate the mechanism underlying the effects on plant growth and development upon exposure to two coumarins. Protein solutions were obtained from giant mimosa seedlings that had been exposed to the coumarins, and they were analyzed with the shotgun proteomic method by liquid chromatography–tandem mass spectrometry (LC–MS/MS). The proteins were identified in seedlings treated with coumarins. The control plants expressed 621 proteins, the plants treated with isoscopoletin expressed 613 proteins, and the plants treated with umbelliferone expressed 640 proteins. The classification of proteins by PANTHER software found that the coumarins interfered with proteins involved in cellular component organization or biogenesis and metabolic processes. STITCH analysis of protein expression after treatment with coumarins confirmed that CUL4, ESF, LNG2 and SCD2 played a role in plant growth and development. WAK1 and WAT1 were involved in cell wall and cell surface responses. At3g61030 and CIP111 were related to Ca2+ accumulation and CAND1, CUL4 and ML5 were linked with programmed cell death. It is worthwhile to mention that coumarins increased morphological changes in the epidermis, Ca2+ accumulation in the roots and protein expression in plant growth and development, morphological changes, Ca2+ accumulation as well as in programmed cell death.