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Biology and Biotechnology of Environmental Stress Tolerance in Plants, Volume 3

Microarray technology has been used successfully to simultaneously

study the expression of thousands of genes in a wide range of genomics,

such as resistance gene identification, drug discovery, and clinical diagnoses

(Beltrame et al., 2007). Gene expression level data contain valuable infor­

mation about biological networks, cell states, and understanding of gene

function. One purpose of analyzing gene expression data is to determine

how the expression of each individual gene affects the expression of other

genes in the same genetic network. Another goal is to determine how genes

are expressed in the control and in the treatment groups.

8.3 MICROARRAY TECHNOLOGY TO STUDY ENVIRONMENTAL

STRESSES

To study environmental stresses microarray technology can be divided into

three parts (Figure 8.1):

• Part I: Chip Design and Preparation: First, the required informa­

tion is collected for the genes to be studied, then the nucleotides are

put together (by software), and the oligonucleotides are made 17 to

25 bp in length. These probes are placed on a glass slide (Kierzek et

al., 2008).

FIGURE 8.1 Microarray technology.