Overexpression of Zm-HINT1 in Arabidopsis thaliana enhances resistance to Fusarium graminearum

Histidine triad nucleotide binding protein 1(HINT1) plays an important role in many biological processes especially in cell biology, and they have been found in a wide variety of species. However, the functional attributes of HINT1 homologues in plants have not yet been reported. We have previously isolated the full-length cDNA of an HINT1 homologue from maize (Zea mays L.), designated as Zm-HINT1. Subcellular localization was analysed after particle-mediated transient transformation of onion epidermal cells. The result revealed that Zm-HINT1 was targeted to the nucleus. Based on real-time PCR analysis, the expression level of Zm-HINT1 increased significantly after salicylic acid or jasmonic acid treatments. To further investigate the potential physiological role of Zm-HINT1, a binary vector was constructed for Zm-HINT1 synthesis and transgenic Arabidopsis lines were generated by Agrobacterium-mediated transformation. Transgenic Zm-HINT1 plants showed increased resistance to Fusarium graminearum compared to the wild type and control plants. Futhermore, real-time PCR results revealed that the pathogen defense genes pathogenesis-related 4 (PR-4) and a peroxidase were upregulated by Zm-HINT1 overexpression. Thus, our data demonstrated that Zm-HINT1 induced antifungal activity against Fusarium graminearum and it may be useful for crop breeding in improving biotic stress tolerance.