VDAC2 involvement in the stress response pathway in Arabidopsis thaliana.

The voltage-dependent anion channel (VDAC) is the major transport protein in the outer membrane of mitochondria, and is involved in the formation of a permeable transition pore and metabolite transport. In this study, we explored the role of Arabidopsis thaliana VDAC2 (AtVDAC2) in the signal transduction pathway in Arabidopsis under salt stress. We investigated the germination rates of AtVDAC2 transgenic lines under salicylic acid (SA) treatment, and found that AtVDAC2 can affect the sensitivity of Arabidopsis to SA. Furthermore, the stomatal apertures of AtVDAC2 transgenic Arabidopsis were calculated. Results showed that the over-expression lines showed the obvious stomatal closure, while in the antisense lines, no obvious changes in stomatal apertures were found. In addition, we also detected the expression levels of salt stress and SA response-associated genes in transgenic plants and found that AtVDAC2 affected the expression of these genes. Our study investigated the role of AtVDAC2 in SA and salt stress response in Arabidopsis; our observations provide some helpful information for better understanding the direct and downstream functions of AtVDAC.

Functional characterization and analysis of the Arabidopsis UGT71C5 promoter region.

In the present study, we isolated an Arabidopsis promoter, UGT71C5, and analyzed its role in the regulation of the light response mechanism. We constructed a fusion vector pBI121-pU-GUS by integrating the UGT71C5 promoter upstream of the GUS reporter gene in pBI121, and then transferred this vector into Arabidopsis plants. The GUS activity of the transgenic plants was detected using a spectrophotometer under normal growth conditions as well as under light, drought, and ABA stress-treatments. The obtained results indicated that the GUS activity of transgenic plants ranged in between the activities observed in wild-type and 35S transgenic plants, which were used as positive control. Light stress for 8 and 12 h increased the GUS activity in transgenic plants by 3 and 4 times, respectively, compared to the activity in these plants under normal conditions. No such change in the GUS activity was observed under drought and ABA-treated conditions. This suggests that the UGT71C5 promoter is light inducible. Our study provides helpful insights into the elucidation of inducible promoters in Arabidopsis and the molecular mechanisms of light response.

Effects of destrin pathway mutations on the gene expression profile.

This study aimed to explore the interaction and crosstalk between pathways in response to destrin mutations. All the pathways from the MINT database were downloaded, a protein-protein interaction network was then constructed, and the crosstalk between pathways was investigated, in particular, the overlap of 2 significant pathway analysis results. As expected, the results showed that regulation of the actin cytoskeleton was the significant pathway of destrin mutations in mice. Further analysis indicated that 28 significant pathways cross-talked with the pathway regulating the actin cytoskeleton. Importantly, 3 pathways, including regulation of actin cytoskeleton pathway, pathways in cancer, and the B cell receptor signaling pathway were linked by inositol phosphate metabolism based on crosstalk analysis of Gene Ontology relationships among pathways. All of these pathways have been demonstrated to participate in cytoskeleton dynamics. These findings might provide valuable insights into cytoskeleton dynamic abnormalities in destrin mutations of corneal diseases.