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As with other environmental stresses, cold stress limits plant growth, geographical distribution, and agricultural productivity. <i>CBF/DREB</i> (<i>CRT</i>-binding factors/<i>DRE</i>-binding proteins) regulate tolerance to cold/freezing stress across plant species. ICE (inducer of <i>CBF</i> expression) is regarded as the upstream inducer of <i>CBF</i> expression and plays a crucial role as a main regulator of cold acclimation. Snow lotus (<i>Saussurea involucrat</i><i>a</i>) is a well-known traditional Chinese herb. This herb is known to have greater tolerance to cold/freezing stress compared to other plants. According to transcriptome datasets, two putative <i>ICE</i> homologous genes, <i>SiICE1</i> and <i>SiICE2</i>, were identified in snow lotus. The predicted <i>SiICE1</i> cDNA contains an ORF of 1506 bp, encoding a protein of 501 amino acids, whereas <i>SiICE2</i> cDNA has an ORF of 1482 bp, coding for a protein of 493 amino acids. Sequence alignment and structure analysis show SiICE1 and SiICE2 possess a S-rich motif at the N-terminal region, while the conserved ZIP-bHLH domain and ACT domain are at the C-terminus. Both <i>SiICE1</i> and <i>SiICE2</i> transcripts were cold-inducible. Subcellular localization and yeast one-hybrid assays revealed that SiICE1 and SiICE2 are transcriptional regulators. Overexpression of <i>SiICE1</i> (<i>35S::SiICE1</i>) and <i>SiICE2</i> (<i>35S::SiICE2</i>) in transgenic <i>Arabidopsis</i> increased the cold tolerance. In addition, the expression patterns of downstream stress-related genes, <i>CBF1</i>, <i>CBF2</i>, <i>CBF3</i>, <i>COR15A</i>, <i>COR47</i>, and <i>KIN1</i>, were up-regulated when compared to the wild type. These results thus provide evidence that SiICE1 and SiICE2 function in cold acclimation and this cold/freezing tolerance may be regulated through a CBF-controlling pathway.