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Genetics and Microarray in Environmental Stress Response

data, in salinity, cold, heat, and light stresses, the regulation of six antioxidant

enzymes in 10 natural Arabidopsis ecotypes was evaluated. The expression

profiles of 36 genes encoding six enzymatic antioxidants including CSD1-3,

FSD1-3, MSD1-2, CAT1-3, APX1-6, APXT, APXS, GPX1-8, MDAR1-5,

and DHAR1-4 were evaluated. In particular, the FSD1, FSD2, CSD1, and

CSD2 genes encode SOD. CAT2 and CAT3 for CAT; APX3-6, APXT, and

APXS for APX, GPX1, GPX2, GPX5, GPX6, and GPX7 for GPX. In low

light and cold stresses, it further up-regulates the expression of genes (Filiz

et al., 2019).

Salinity is one of the most important environmental stresses that reduces

growth and yield in plants (Hill et al., 2016). The expression pattern of 1,728

genes in response to salinity stress in rice was investigated by microarray

method (Kamaluldeen et al., 2014). Also, a study examined the expression

pattern of 32,000 genes in response to salinity stress in wheat, a total of 3,416

genes increased in salinity and 2,580 genes showed decreased expression

(Kawaura et al., 2008). As previously mentioned, low throughput methods

are used to confirm the results of microarrays, for example, in a study by

Salami et al. (2017), the expression analysis of Hv TIP2;3 and Hv TIP4;1 in

barley genotypes under salinity stress was performed by real-time method.

Identification of new genes and determination of their expression pattern is

done with the aim of adapting plants to different types of stresses, and in this

regard, effective solutions should be created in plant modification to improve

stress tolerance.

8.6 CONCLUSION

Plants are subject to various environmental stresses during their growth and

development. The response to these stresses involves changes at the cellular

and molecular levels. Microarray provides a new opportunity for biological

search, including the explanation of genes in specific processes such as cell

cycle, growth, and development, the evaluation of the effects of chemical

and genetic disorders, and the identification of genes. Identification of toler­

ance mechanisms and genes involved in stress response with the help of

powerful microarray technology can help to take measures to improve toler­

ance to various stresses in crops and improve their performance by methods

such as genetic engineering. Microarray is based on gene network. Different

methods can be proposed to reconstruct gene regulatory networks, such as

protein interaction networks and gene expression networks to identify hub

genes.