IN SEARCH OF DIFFERENTIALLY EXPRESSED GENES AND PROTEINS

A great challenge for modern cell biology is the successful examinatio n of the co-expression of thousands of genes under physiological or pa thological conditions and how the expression patterns define the diffe rent states of a single cell, tissue or a microorganism. Gene expressi on can be analyzed today on a large scale by advanced technical approa ches for differential screening of proteins and mRNAs. The identificat ion of differentially expressed mRNAs has been successfully applied to understand gene function and the underlying molecular mechanism(-s) o f differentiation, development and disease state. Analysis of gene exp ression by the systematic mapping of thousands of proteins present in a cell or tissue can be achieved by the use of two-dimensional (2D) ge l electrophoresis, quantitative computer image analysis, and protein i dentification techniques. In this article, we comment on some of these techniques and try to stress their advantages and drawbacks. We show how data from RNA/DNA mapping, sequence information from genome projec ts and protein pattern profiling can be linked with each other and ann otated. These comprehensive approaches permit the study of differentia l gene and protein expressions in cells or tissues. (C) 1997 Elsevier Science B.V.