2 Dimensional Apparatus
GE Healthcare, USA
Proteins
are biochemical compounds consisting of one or more polypeptides typically
folded into a complex formed facilitating a biological function. The analysis
of the proteomic organization of the cell requires techniques conserving the
native state of the protein complexes. In 1975, P. H. O'Farrell and J. Klose
introduced 2-dimensional electrophoresis which separates proteins according to
two independent properties in two different steps: the first dimension step,
isoelectric focusing (IEF), separates proteins according to their isoelectric
points (pI); the second dimension step, SDS-Polyacrylamide Gel Electrophoresis
(SDS-PAGE), separates protein according to their molecular weights. Two-dimensional electrophoresis (2-D
electrophoresis) is a powerful and widely used method for the analysis of
complex protein mixtures extracted from cells, tissues, or other biological
samples. Thousands of different proteins can be separated, and information such
as pI of the protein, apparent molecular weight, and amount of each protein can
be obtained. The spots will then be used for further analysis like MALDI TOF,
LC-MS/MS, etc. 2-dimensional electrophoresis has several applications. For
example, by comparing the proteins from normal and cancer cells,
cancer-specific proteins can be identified and developed into markers for
cancer diagnosis, or drug target for cancer treatment.