Characterization and functional analysis of transcription factor ZmEIL1 in maize

Abstract

As key nuclear transcription factors, the ethylene-insensitive3/EIN3-like (EIN3/EIL) proteins play important roles in ethylene signal transduction pathway in various plants. In order to better understand the role of EIN3/EILs, one EIN3-like gene (designated ZmEIL1) was isolated from maize (Zea mays L.). The full-length cDNA of ZmEIL1 was 1 999 bp in length and encoded 647 amino acids. Sequence comparison of ZmEIL1 protein with other EIN3/EILs proteins revealed high conservation of five α-helices that could form a V-shaped cleft in a 3-D model, just like AtEIL3 in Arabidopsis thaliana. This protein showed transcriptional activation and activation domain located on the 507 - 647 amino acids in yeast. Furthermore, ZmEIL1 could interact with ZmERF1 in the yeast systems, which was downstream response factor in ethylene signal transduction pathway. Its mRNA could be highly induced in maize seedlings by ethephon and 1-methylcyclopropene treatments. Meanwhile, ZmEIL1 showed relatively high expression at 20 d after pollination in maize kernel. These results show that ZmEIL1 played an important role in the growth and development by participating in ethylene signalling pathway in maize.