A putative maize zinc-finger protein gene, ZmAN13, participates in abiotic stress response

The maize ZnF-AN1 gene family has been phylogenetically studied. Here, we tried to characterize the possible function of ZmAN13, a putative member of the maize ZnF-AN1 gene family. The results showed that ZmAN13 had only one copy in the maize genome. The expression of ZmAN13 was higher in leaves than other organs and was induced by cold and abscisic acid (ABA), but down-regulated by NaCl. ZmAN13 protein fused to GFP was localized in cytoplast and also in the nucleus in both Arabidopsis protoplast and onion epidermic cells although no transcription factor activity was detected in the yeast system. Yeast two hybrid experiments demonstrated that the conserved A20 and AN1 domains of the ZmAN13 interacted with each other. Moreover, the conserved A20 domain of the ZmAN13 interacted with itself, but the AN1 domain could not. Overexpression of ZmAN13 in Arabidopsis conferred tolerance to cold, but increased their salt and drought sensitivity at seed germination and seedling stage compared to the wild-type.