Abstract: We isolated two transcription factor genes, named as CpHRD and SaHRD, from two kinds of ephemeral Conringia planisiliqua L. and Sisybrium altissimum L. by RT-PCR, respectively. By bioinformatics, both of CpHRD and SaHRD are possessing an intact complete open reading frame of 564 bp and sharing 88%, 87%, 87% and 86% of sequence identity with Eutrema salsugineum, Arabidopsis lyrata, Capsella rubella and Arabidopsis thaliana, respectively. The deduced polypeptide sequence of CpHRD and SaHRD are 187 amino acid residues with a predicted molecular weight of 20 kD with secondary protein structure of the polypeptide chains contain including 2 β-sheets, 5 α-helixs and random coils, belonging to hydrophilicity and stable of transmembrane protein. By phylogenetic tree analysis, CpHRD and SaHRD mainly exist in the nucleuscontains, and have a typical AP2/EREBP domain function structure, which may be involved in plant stresses response process of ABA, drought and low temperature. Our results can provide useful information about the molecular mechanism of HRD genetic mechanism of drought resistance, and will contribute a valuable resource for development and utilization of germplasm resources of ephemeral plant.

Key words: ephemeral plant, HRD gene, transcription factors, gene cloning, bioinformatics analysis