Role of the zinc finger homeodomain (ZFHD) and NAC transcription factors in drought-inducible expression of the erd1 gene

Abstract

The dehydration-dependent expression of the erd1 gene is under the control of co-operative activity of two cis elements, NACRS (NAC recognition sequence) and ZFHDRS (zinc finger homeodomain recognition sequence). Last year, we reported the isolation and functional analyses of three NACRS binding NAC transcriptional activators. Recently, a ZFHDRS binding ZFHD1 transcriptional activator was isolated using yeast one-hybrid system. ZFHD1 protein specifically binds to ZFHDRS both in vitro and in vivo. The expression of ZFHD1 gene was induced by drought, high salinity and ABA. The ZFHD1 and NAC transcriptional activators co-operatively transactivated expression of the GUS reporter gene driven by the erd1 promoter in Arabidopsis T87 protoplasts. Yeast two-hybrid system detected interaction between ZFHD1 & NAC proteins.