Research On Differential Proteomics About Regeneration Of Schmidtea Mediterranea Planarian

Regeneration is the organism repairing the whole body process after injured or being cut, through forming the new tissues or organs to replace it. In the biological world, the phenomenon of regeneration exists everywhere, which inspired the scientists to study the mechanism of regeneration.Freshwater planarian (Schmidteam editerranea), also known planarian, which belongs to Platyhelminthes, is a kind of free-living animals. Because of its amazing ability to regenerate, it is the ideal model organism for regeneration research. To study the mechanism of planarian regeneration will help us to comprehend the mechanism of human regeneration in the future, which has important scientific significance in the organs'regeneration and transplantation.This experiment intends to take the regeneration and normal tissue of planarian as the research object, have proteomics related-technology as a means, use two-dimensional gel electrophoresis to separate total protein of two planarians organizations, build the protein expression profiles in two different states of planarians. To identify differentially expressed proteins after analysis and comparison the profiles. These proteins are then analyzed by mass spectrometry and bioinformatics analysis. Thus we determine the expression of regeneration-specific protein, which can further explore the gene encoding the protein's role in regeneration.Firstly, we extracted the total protein from the two different tissues, and separated them by two-dimensional gel electrophoresis (2-DE) after washing and precipitating the protein respectively. By silver staining, UMax Powerlook scanner scanning and analysising the images by ImageMasterTM software, we identify differentially expressed protein spots. Then we cut the difference points to be digested by Trypsin,and then analysis them by tandem matrix-assisted laser desorption ionization time of flight mass spectrometry (MADLI TOF-TOF) to get the peptide mass fingerprinting (PMF). Using the Mascot protein database search software in the NCBInr database to identified these differentially proteins. After the basis of the points of each protein peptide, through a planarians protein database to search the corresponding amino acid sequences and nucleotide sequences.Then we got the two-dimensional electrophoresis gels having the better repeatability and resolution about the two different tissues. And we also obtained 132 differentially expressed proteins, and then identified 21 different proteins points which has significant differentially expression by mass spectrometry (MS). By comparing the differences proteins of normal tissue and regeneration tissue of planarian, we found that most of these proteins exist in these two kinds of tissue, just as a down-regulated expression in the regeneration, which indicated that these proteins may be in recycling low or no expression for the regeneration.Lastly, the MS results show there are 15 protein spots highly expressed in normal tissues; three points in regeneration tissue highly expressed. Only two proteins expressed in normal and one in regeneration. This result shows that these proteins may be play a role in the process of planarian regeneration. Moreover, according to the results of identification and functional analysis, we found that most of these proteins are cytoskeletal proteins. It suggested these proteins play an important role in the body reconstruction when planarian happens to regenerate.