ABSTRACT
Knowledge about life processes has expanded dramatically during the 20th century and produced the modern disciplines of genomics and proteomics. However, there remains the great challenge of discovering the integration and regulation of living components in time and space within the cell. As we move into the postgenomic period, the complementarity between genomics and proteomics will become apparent, and the connections between them will be exploited, although genomics, proteomics, or their simple combination will not provide the data necessary to interconnect molecular events in living cells in time and space. The cells in a group are different entities, and differences arise even among cells grown in homogeneous conditions considered to have identical genetic information. These cells respond differently to perturbations.
