Zinc finger protein 1 (ThZF1) from salt cress (Thellungiella halophila) is a Cys-2/His-2-type transcription factor involved in drought and salt stress.

Zinc finger proteins (ZFPs) play important roles in growth and development in both animals and plants. Recently, some Arabidopsis genes encoding distinct ZFPs have been identified. However, the physiological role of their homologues with putative zinc finger motif remains unclear. In the present study, a novel gene, ThZF1, was characterized from salt stressed cress (Thellungiella halophila, Shan Dong), encoding a functional transcription factor. ThZF1 contains two conserved C(2)H(2) regions and shares conserved domains, including DNA-binding motif, with Arabidopsis thaliana ZFP family members. The transcript of the ThZF1 gene was induced by salinity and drought. Transient expression analysis of ThZF1-GFP fusion protein revealed that ThZF1 was localized preferentially in nucleus. A gel-shift assay showed that ThZF1 specially bind to the wild-type (WT) EP2 element, a cis-element present in the promoter regions of several target genes regulated by ZFPs. Furthermore, a functional analysis demonstrated that ThZF1 was able to activate HIS marker gene in yeast. Finally, ectopic expression of ThZF1 in Arabidopsis mutant azf2 suggested that ThZF1 may have similar roles as Arabidopsis AZF2 in plant development as well as regulation of downstream gene.