Plant stress-inducible promoters and their function

Promoter is an important cis-regulatory element for gene expression and plays an important role in the process of plant gene expression and regulation. Constitutive promoters are being used to drive alien gene expression in most transgenic engineering. Although constitutive promoters can improve resistance of transgenic plants to abiotic stresses, over- and constitutive-expression of the alien genes have been shown to cause stunted growth and reduction of yield in transgenic plants. Therefore, inducible promoters, which are expressed only when exposed to stresses, are of importance. This paper reviews the types and functions of plant gene promoters induced by bio- and abio-stresses. The prospect of stress-induced promoters was discussed.