The Peptidomics Of Cell Apoptosis And Rice Based On NanoLC-MS/MS

Peptidomics has attracted widespread attention since birth.Peptidomics studied the cell small peptides with certain functions which could not been found by the proteomics ways.In the present study,we learned about the apoptosis process and salt stress process in pepdomics.Apoptosis is the process of programmed cell death that may occur in multicellular organisms.In contrast to necrosis,which is a form of traumatic cell death that results from acute cellular injury,in general apoptosis confers advantages during an organism's lifecycle.Currently more of the studies focus on the relationship between apoptosis and cancer or various autoimmune diseases.There were many studies about the apoptosis based on proteomic.For a clearing understanding of the changes of peptides in apoptosis process,we checked the peptidome of the cells at the stage of apoptosis.In this study,we treated the Hela cells with hydrogen peroxide?H₂O₂?as an oxidative stress model and observed the changes of peptides in apoptotic cells.The main results as follows:1.To determine the type of cell death induced by H₂O₂ in HeLa cells,we measured the percentage of apoptotic HeLa cells using AnnexinV-FITC/PI flow cytometry.Hela cells were treated with 1 mM,2 mM and 5 mM of H₂O₂ for 6 h.When the cells reached 3.5 million,treatment of cells with 5 mM H₂O₂,40% apoptosis after 6 h,and the cells almost in late apoptotic state.2.We incubated Hela cells for 6h with either medium alone,or medium containing 2 or 5 mMH₂O₂ and detected 385 peptides in Hela cells,of which we were able to in total identify 93 proteins with significant variations.In our study,only 30 peptides are internal fragments,and mainly correspond to C-or N-terminal fragments.These 93 protein precursors of peptides are associated with protein metabolic process,apoptotic process,cell cycle and so on.Bioactive plant peptides play important roles in plant growth and development and insect resistance.However,the systematic research on the plant peptidomics are still rare.In the present study,the exploration of extracting and detection of natural plant peptides in rice were performed.The plant peptides were extracted by urea and detected using nanoLC-MS/MS instrument.About 110 peptides were identified in rice leaves and roots,and they distributed in many active sites through the peptide cellular localization.The results indicated that these peptides might be involved in important physiological activities of rice.