State Key Laboratory of Tree Genetics and Breeding, Chinese Academy of Forestry, Beijing 100091, China.
Key Laboratory of Tree Breeding of Zhejiang Province, The Research Institute of Subtropical of Forestry, Chinese Academy of Forestry, Hangzhou 311400, China.
Int J Mol Sci. 2018 Apr 17;19(4):1216. doi: 10.3390/ijms19041216.
Hance, a cadmium (Cd)/zinc (Zn)/lead (Pb) co-hyperaccumulating species, is a promising phytoremediation candidate because it accumulates substantial amounts of heavy metal ions without showing any obvious signs of poisoning. The heat shock transcription factor (Hsf) family plays crucial roles in plant growth, development, and stress responses. Although the roles of some Hsfs in abiotic stress have been well studied in model plants, the Hsf family has not been systematically investigated in heavy metal hyperaccumulators. Here, we comprehensively analyzed the gene family in based on a transcriptome under Cd stress. There were 22 members that were identified and phylogenetically clustered into three classes, namely, SaHsfA, SaHsfB, and SaHsfC. All of the three classes shared similar motifs. The expression profiles of the 22 members showed significant differences: 18 were responsive to Cd stress, as were multiple genes, including , , , , and . Two class A4 members, and , exhibited transcriptional activation activities. Overexpression of and in transgenic yeast indicated an improved tolerance to Cd stress and Cd accumulation. Our results suggest play important regulatory roles in heavy metal stress responses, and provide a reference for further studies on the mechanism of heavy metal stress regulation by .
山黧豆是一种镉（Cd）/锌（Zn）/铅（Pb）共超积累物种，因为它在没有表现出明显中毒迹象的情况下积累了大量重金属离子，所以是一种很有前途的植物修复候选物。热休克转录因子（Hsf）家族在植物的生长、发育和应激反应中起着至关重要的作用。虽然一些 Hsfs 在模式植物中的非生物胁迫中的作用已经得到了很好的研究，但重金属超积累植物中的 Hsf 家族尚未得到系统研究。在这里，我们根据 Cd 胁迫下的转录组，全面分析了山黧豆中的基因家族。共鉴定出 22 个成员，并根据系统发育聚类为三个类，即 SaHsfA、SaHsfB 和 SaHsfC。这三个类都具有相似的基序。22 个成员的表达谱显示出显著的差异：18 个对 Cd 胁迫有反应，多个基因也是如此，包括 、 、 、 、 和 。两个 A4 类成员 和 表现出转录激活活性。在转基因酵母中过表达 和 表明对 Cd 胁迫和 Cd 积累的耐受性提高。我们的结果表明 在重金属胁迫反应中发挥重要的调控作用，并为进一步研究 调节重金属胁迫的机制提供了参考。
