Gene Expression Profiling Research Articles

Genes encode proteins and proteins dictate cell function. Therefore, the thousands of genes expressed during a particular cell determine what that cell can do. Moreover, each step within the flow of data from DNA to RNA to protein provides the cell with a possible control point for self-regulating its functions by adjusting the amount and sort of proteins it manufactures.At any given time, the quantity of a specific protein during a cell reflects the balance between that protein's synthetic and degradative biochemical pathways. Thus, control of those processes plays a critical role in determining what proteins are present during a cell and in what amounts. In addition, the way during which a cell processes its RNA transcripts and newly made proteins also greatly influences protein levels. Transcript processing provides a further level of regulation for eukaryotes, and therefore the presence of a nucleus makes this possible. In prokaryotes, translation of a transcript begins before the transcript is complete, thanks to the proximity of ribosomes to the new mRNA molecules. In eukaryotes, however, transcripts are modified within the nucleus before they're exported to the cytoplasm for translation.Eukaryotic transcripts also are more complex than prokaryotic transcripts. For instance, the first transcripts synthesized by RNA polymerase contain sequences which will not be a part of the mature RNA.