A WHEAT CALRETICULIN GENE (TACRT1) CONTRIBUTES TO DROUGHT TOLERANCE IN TRANSGENIC ARABIDOPSIS

The TaCRT1 gene is a member of calreticulin (CRT) family in wheat. In our previous study, we showed that transgenic tobacco lines over expressing wheat TaCRT1 showed enhanced tolerance to salt stress. This study aimed to determine whether TaCRT1 over expression would increase drought tolerance in transgenic Arabidopsis. Over expression of TaCRT1 in Arabidopsis plants enhances tolerance to drought stress. However, the transgenic line was found to retard the growth. Moreover, the transgenic line showed decreased water loss but higher sensitivity to exogenous abscisic acid (ABA) compared with the wild type (Col-0). Meanwhile, the transgenic line had the elevated endogenous ABA level. The semi quantitative RT-PCR (sqRT-PCR) analysis showed that transcription levels of ABA-biosynthesizing gene (NCED3) and ABA-responsive gene (ABF3) were higher in the transgenic line than that in the Col-0 under normal condition. The above results implied that the TaCRT1 might be able to used as a potential target to improve the drought tolerance in crops.