Molecular cloning and characterization of a novel ice gene from Capsella bursa-pastoris

A new ice gene (designated as Cbice53, an inducer of CBF expression) was cloned from Capsella bursa-pastoris by rapid amplification of cDNA ends (RACE). The full-length cDNA of Cbice53 was 1811 bp long, with a 1476-bp open reading frame (ORF) encoding a Myc-like protein of 492 amino acids. The predicted CbICE53 protein contained a potential basic helix-loop-helix domain, a nuclear localization signal (NLS), an RNA-binding region (RGG box), and N-glycosylation and kinase phosphorylation sites. Bioinformatic analysis showed that CbICE53 was highly homologous to ICE1 from Arabidopsis thaliana. Transcription of Cbice53 gene was induced transiently during salt and cold treatments, suggesting that it was somehow involved in cold acclimation. The results of our study indicate that the Cbice53 gene is a new member of the ice gene family and may have a role in cold and salt responsiveness in C. bursa-pastoris.