IDENTIFICATION OF PROTEINS AFTER TWO DIMENSIONAL ELECTROPHORESIS BY PEPTIDE MASS FINGERPRINTING USING MALDI-TOF-MS

摘要

With the rapid development of DNA sequencing technology, more and more genes have been sequenced, and the human genome project will be completed in 5 years. Now the post-genome era, proteome era has come. Proteome means the whole proteins expressed by genome in a cell or tissue. Studying of proteome can reveal many problems that can't be solved only by genome project. For example how the proteins of cell to be post-translation modified and how to compare the proteins of health cell with that of disease cell, the relation between gene and its function also can be investigated. The basic technologies of proteome mainly consist of two parts, one is separating the whole proteins of a cell, and the other is identifying the separated proteins. Two-dimensional electrophoresis (2-DE) is now the most powerful separating technique and the key method of separation in proteome. Identification of proteins separated by 2-DE has many ways such as immunoblotting, N- or C- terminal microsequencing, internal sequence tag and peptide mass fingerprinting (PMF). With the advances of MS technology, the mass accuracy of peptide measured by MALDI-TOF-MS can reach 0.1%-0.01%. Now peptides mass has been the very important data used to identify proteins in proteome project. In this study, proteins isolated from human lung cancer cell (PLA-801) by 2-DE have been identified by PMF and database searching.