Fig. S1 Fig. S1 Splicing variants of HRE1. a Schematic maps of the HRE1 gene and its splicing variants, HRE1α and HRE1β transcripts. AUG and UGA* indicate start codon and stop codon, respectively. b The amino acid sequence alignment of HRE1α and HRE1β. AP2/ERF domains of both HRE1α and HRE1β transcripts were presented. Alignment was made by ClustalW using default parameters. Fig. S2 Fig. S2 Expression analysis of HRE1α under abiotic stress conditions. Quantitative RT-PCR analysis of HRE1α under 300 mM NaCl (a), 300 mM mannitol (b), 100 μM ABA (c), or 10 µM MV (d) for the indicated times. GAPc was used as an internal control. Transcript levels at 0 h were set to 1. Reactions of each technical replicate were performed in triplicate. Two technical replicates were measured for each biological replicate. Data shown are the means ± SD (n = 6). Similar results were obtained from at least two biological replicates, with one shown here. Fig. S3 Fig. S3 Generation of HRE1α OXs. Schematic map of plant expression vector for overexpression of HRE1α, and expression analysis of HRE1α in HRE1α-overexpressing T1 lines by semi-quantitative RTPCR. Circled lines were selected for further analysis. GAPc was used as an internal control. Table S1 Primers used in this study Gene Forward Reverse HRE1α 5′-CTTTATCCATGGCTAGGCTC-3′ 5′-ACTCCTTTGATTGGATCACG-3′ GAPc 5'-GTGTCCCAACCGTTGATGTC-3' 5'-TCCCTTGAGTTTGCCTTCGG-3' HRE1α 5'-CTTTATCCATGGCTAGGCTC-3' 5'-TCAAGACAGCTACTACTAGG-3' GAPc 5'-CACTTGAAGGGTGGTGCCAAG-3' 5'-CCTGTTGTCGCCAACGAAGTC-3' HRE1 promoter 5'-GCGAAGCTTTTGATAATTAAAAAGAAAAT-3' 5'-GCGCTGCAGAGAACCAAACGATGAACATA-3' Cloning HRE1α OX 5'-CGCGTCGACATGTCTCAAAGCTTTGAACT-3' 5'-GATGGATCCTCAGGACCATAGACCCATGT-3' Cloning sGFP 5'-ATCCTGCAGATGGTGAGCAAGGGCGAGGAG-3' 5'-ATCGTCGACCTTGTACAGCTCGTCCATGCC-3' Cloning 5'-CAGGAATTCATGTCTCAAAGCTTTGAACT-3' 5'-CAGGTCGACTCAGGACCATAGACCCATGT-3' Cloning HRE1α N160 5'-CAGGAATTCATGTCTCAAAGCTTTGAACT-3' 5'-CGCGTCGACGTTGGCTTCTTCACTATCAT-3' Cloning HRE1α N145 5'-CAGGAATTCATGTCTCAAAGCTTTGAACT-3' 5'-CACGTCGACGCCCATGATGATATCTTCGA-3' Cloning HRE1α N136 5'-CAGGAATTCATGTCTCAAAGCTTTGAACT-3' 5'-CGCGTCGACTGTATCAATCAGAAGCGTGT-3' Cloning HRE1α N130 5'-CAGGAATTCATGTCTCAAAGCTTTGAACT-3' 5'-ATAGTCGACGTCCGGATTATTCTCCTCCC-3' Cloning HRE1α N120 5'-CAGGAATTCATGTCTCAAAGCTTTGAACT-3' 5'-ACAGTCGACAAGACAGCTACTACTAGGCG-3' Cloning HRE1α N87 5'-CAGGAATTCATGTCTCAAAGCTTTGAACT-3' 5'-ACAGTCGACCTTTCCAGAGGATTCGTTAG-3' Cloning 5'-GCGCTCGAGTTGAGACTTTTCAACAAAGG-3' 5'-CACGTCGACGTCCTCTCCAAATGAAATGA-3' Cloning 5'-GCGCTGCAGTTATTGTTCATTTTTGAGAA-3' Cloning 5'-ATACCCGGGGAATTTCCCCGATCGTTCAA-3' 5'-GCGTCTAGACCGATCTAGTAACATAGATG-3' Cloning 5'-CAAGAATTCGCAAGACCCTTCCTCTAT-3' 5'-ATACTGCAGCAGCGTGTCCTCTCCAAA-3' Cloning Firefly luciferase 5'-CGCGGATCCATGGAAGACGCCAAAAACAT-3' 5'-CAGTCTAGATTACACGGCGATCTTTCCGC-3' Cloning Nos terminator 5'-ATACCCGGGGAATTTCCCCGATCGTTCAA 5'-GTCGAGCTCGAATTTCCCCGATCGTTCAA Cloning HRE1α entire ORF CaMV 35S promoter Renilla luciferase Nos terminator CaMV 35S promoter core Purpose Quantitative RT-PCR 5'-CGCGTCGACAAAAATG ACTTCGAAACTTTATGA-3' Quantitative RT-PCR Semi-quantitative RT-PCR Semi-quantitative RT-PCR