Anti-stress Function of AtPDI1 Linked to Disulfide Isomerase Activity

Shandong Agricultural University scientists reported that the thiol-disulfide exchange activity of Arabidopsis protein disulfide isomerase 1 (AtPDI1) is involved in the response to abiotic stresses. Their findings are reported in BMC Plant Biology.

Previous studies have shown that AtPDI has disulfide isomerase activity and to be involved in the stress response. However, it was unknown if anti-stress function is directly related to the activities of thiol-disulfide exchange. Thus, the researchers conducted a study wherein the encoding sequences of AtPDI1 of wild-type and double-cysteine-mutants were transformed into an AtPDI1 knockdown Arabidopsis line (pdi), and homozygous transgenic plants named pdi-AtPDI1, pdi-AtPDI1m1 and pdi-AtPDI1m2 were obtained.

Results showed that the germination ratios of pdi-AtPDI1m1 and pdi-AtPDI1m2 were significantly lower under abiotic stresses and exogenous ABA treatment, while the highest germination rate was obtained with AtPDI1 overexpression in the WT (WT- AtPDI1). In terms of the root length, a higher germination rate was observed with a longer root length. When seedlings were exposed to various stresses such as salt, drought, cold, and high temperature, pdi-AtPDI1m1, pdi-AtPDI1m2 and pdi displayed lower survival rates than WT and AtPDI1 overexpression plants.

Based on the results, the anti-stress function of AtPDI1 is strongly linked to the activity of disulfide isomerase.

Read more findings in BMC Plant Biology.