Transcript Profiling Methods

Several methods have been used for high-throughput gene expression analysis; they include sequence analysis of cloned transcripts [differential display, subtrac-

Figure 9.1

Steps involved in microarray-based gene expression analysis tive hybridization, serial analysis of gene expression (SAGE) and sequencing of expressed sequence tags (ESTs)], and the use of microarrayed sequence probes for quantitative hybridization studies. Sequencing-based techniques can be very quantitative and precise but are dependent on the depth of sequencing, accurate sequencing, and authentic mapping of sequence to gene. They are also labor intensive. Microarray-based hybridization studies involve labeling of transcript representations from cells or tissues and hybridization of the labeled target to nucleic acid probes attached to a solid support in an arrayed pattern (Fig. 9.1). The bound label is proportional to the quantity of specific transcripts in the original RNA mixture. The probe arrays are miniaturized such that thousands of individual probes can be attached to a very small substrate providing high-throughput and experimental efficiency. This technique allows for the efficient analysis of virtually unlimited numbers of genes.

0 0

Post a comment