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

TABLE 7.1 (Continued)

TF

Gene

Transgenic

Effect

References

Plant

bHLH

AtbHLH68

Arabidopsis

↑ Drought

Le et al. (2017)

PebHLH35

Arabidopsis

↑ Drought

Dong et al. (2014)

ZmPTF1

Maize

↑ Drought

Li et al. (2019)

AtbHLH112

Arabidopsis

↑ Drought/salt

Liu et al. (2015)

BcICE1

Canola

↑ Cold

Zhang et al. (2018)

OsbHLH068

Arabidopsis

↑ Salt

Chen et al. (2017)

TabHLH39

Arabidopsis

↑ Salt/drought/cold

Zhai et al. (2016)

FtbHLH2

Arabidopsis

↑ Cold

Yao et al. (2018)

FtbHLH2

Arabidopsis

↑ Cold

Yao et al. (2018)

FtbHLH3

Arabidopsis

↑ Drought/oxidative

Yao et al. (2017)

AH

Tomato

↑ Low temperature

Qiu et al. (2016)

DIICE1

Arabidopsis

↑ Cold

Yang et al. (2019)

PubHLH1

Tobacco

↑ Cold

Jin et al. (2016)

ThbHLH1

Arabidopsis

↑ Osmotic stress

Ji et al. (2016)

ZmPTF3

Maize

↑ Drought

Gao et al. (2018)

GmbHLH57

Soybean

↑ Fe deficiency

Li et al. (2018)

TabHLH1

Tobacco

↑ Pi/N starvation

Yang et al. (2016)

OsbHLH035

Rice

↑ Salt

Chen et al. (2018)

PtFIT

Populus

↑ Iron

Huang & Daim (2015)

ILR3

Arabidopsis

↑ Iron

Samira et al. (2018)

TabHLH49

Wheat

↑ Drought

Liu et al. (2020)

AtbHLH68

Arabidopsis

↑ Drought

Le et al. (2017)

AtbHLH18

Arabidopsis

↑ Fe deficiency

Cui et al. (2018)

Transcription factors constitute an integral part of the genetic circuits

which dynamically regulate gene networks to enhance plant stress tolerance.

DNA-binding domains (DBD) of plant TFs can be replaced with engineered

zinc fingers or TAL effectors to meet specific needs (Beerli & Barbas, 2002;

Townsend et al., 2009). Consequently, engineering DBD strategy of the TFs

facilitate binding of TFs to any target genomic sequence in plants (Gitzinger

et al., 2009; Lu et al., 2009). Synthetic/Artificial TFs (ATFs) are promising

alternative to naturally occurring TFs and composed of a translational fusion

of DBD and effector domains (ED: repressor or activator). ATFs have DNA

binding specificity and potential to act on particular promoter to carryout acti­

vation or repression of a specific gene. Previously genome editing tools (ZF

domains and TALEs) have been extensively used to design DBDs for ATFs.