bHLH是一类重要的转录因子，在植物生长发育及抗逆调控中起重要作用。我们从柽柳中克隆了一个bHLH基因，其在拟南芥中过表达显著提高了转基因植物的耐盐性。除结合G-box外，bHLH还特异性地结合W-box、LTRE1和LTRE15元件，且在盐胁迫下对这三种元件的结合力显著增强，而对G-box的结合则不受盐胁迫调控，提示这三个元件在逆境下bHLH对基因的调控中起作用。因此，我们拟通过ChIP-Seq比较盐胁迫和非胁迫下这些元件在bHLH调控基因的启动子中分布和出现频率，并结合ChIP定量PCR分析，阐明这些元件在bHLH调控基因表达中的功能，并进一步揭示它们控制的基因所涉及的生物过程及途径。利用免疫共沉淀技术确定与bHLH互作的蛋白，并进一步研究bHLH与这些蛋白互作后对顺式作用元件结合的影响，进而阐明bHLH调控基因表达来响应逆境胁迫的机理。

bHLH is a kind of important transcription factor, which play important role in growth and stress tolerance of plants. A bHLH gene had been cloned and characterized from Tamarix hispida, and was transformed into Arabidopsis plants. The transgenic Arabidopsis plants overexpressing bHLH displayed significant improved stress tolerance; meanwhile, besides binding to G-box, this bHLH is found to also bind to W-box, LTRE1 and LTRE15. Additionally, the binding affinities of bHLH to W-box, LTRE1 and LTRE15 are induced, while the binding of bHLH to G-box is not responding to salt stress. These results indicated that W-box, LTRE1 and LTRE15 play roles in stress response mediated by bHLH. Based on these studies, the distribution and occurrence of the motifs of G-box, W-box, LTRE1 and LTRE15 in the promoters of genes targeted by bHLH will be compared between under normal and salt stress conditions using ChIP-Seq analysis. These results are combined with ChIP quantitative PCR to reveal the functional roles of these motifs in the gene expression regulation of bHLH. The pathways and processes involved in these motifs will be further studied. The protein partners interacted with bHLH will be studied using Co-Immunoprecipitation, and the effects of the motif binding caused by the interaction of bHLH with other proteins are further investigated. These studies together will reveal the salt stress tolerant mechanism mediated by bHLH.