Transcription factor WRKY46 regulates osmotic stress responses and stomatal movement independently in Arabidopsis.

Drought and salt stress severely inhibit plant growth and development; however, the regulatory mechanisms of plants in response to these stresses are not fully understood. Here we report that the expression of a WRKY transcription factor WRKY46 is rapidly induced by drought, salt and oxidative stresses. T-DNA insertion of WRKY46 leads to more sensitivity to drought and salt stress, whereas overexpression of WRKY46 (OV46) results in hypersensitivity in soil-grown plants, with a higher water loss rate, but with increased tolerance on the sealed agar plates.

Establishment of an inducing medium for type III effector secretion in Xanthomonas campestris pv. campestris.

It is well known that the type III secretion system (T3SS) and type III (T3) effectors are essential for the pathogenicity of most bacterial phytopathogens and that the expression of T3SS and T3 effectors is suppressed in rich media but induced in minimal media and plants. To facilitate in-depth studies on T3SS and T3 effectors, it is crucial to establish a medium for T3 effector expression and secretion. Xanthomonas campestris pv.

[Expression profiles of AtWRKY25, AtWRKY26 and AtWRKY33 under abiotic stresses.].

The transcription factor WRKY family is one type of key regulatory components of plant development and defense against stress factors. The expression profiles of three AtWRKY genes under abiotic stresses were analyzed by Northern blotting analysis. The expression of AtWRKY25, AtWRKY26, and AtWRKY33 changed during stress treatments including thermal factors, NaCl, abscisic acid (ABA) and osmotic stress, and significantly under NaCl and cold treatments, suggesting a specific role of the three AtWRKYs in adaptation to environmental stresses in plants.

[Expression profile analysis of Peptide5 and Peptide6 in Arabidopsis].

Two predicted peptide genes in Arabidopsis thaliana L., Peptide5 and Peptide6, was confirmed by RT-PCR in mRNA level. The expression profile indicated that both genes were generally expressed at different developmental stages and tissues as constitutive gene expression, and they also responded to six treatments including NaCl, PEG, MeJA (methyl jasmonate), SA (salicylic acid), cold and wound in transcription level.

[Construction of plant expression vectors containing the gene encoding cholera toxin B subunit].

Objective: To construct the plant expression vector containing the nucleotide sequence encoding cholera toxin B (CTB) subunits.

Method: Using high-fidelity PCR, we amplified CTB genes that were then subcloned into the transition vector pRTL2. Following confirmation of the CTB nucleotide sequence, the vector was subcloned into the plant vector pBI121 that was subsequently transferred into Agrobacterium tumefaciens LBA4404 by electroporation.