目的 筛选使鱼腥草Houttuynia cordata具有不同环境适应性的候选bZIP基因，为后续繁育出具有更强环境适应性的鱼腥草品种奠定基础。方法 以鱼腥草转录组数据为基础，鉴定了HcbZIP基因家族成员，并对其理化性质、系统进化树、motif基序及在2个不同生态型鱼腥草中的表达进行分析。结果 共鉴定得到163个HcbZIP基因，编码蛋白质的氨基酸数量在115（HcbZIP48和HcbZIP149）～703 aa（HcbZIP97），超过53%的家族成员为碱性蛋白，超过84%的家族成员为不稳定蛋白，所有家族成员均为亲水性蛋白。二级结构中，161个家族成员是由α-螺旋、延伸链、β-折叠和无规则卷曲4部分构成，β-折叠所占比例最低，α-螺旋和无规则卷曲所占比例较高。系统进化树分析将163个家族成员分成了9个类别，包括C、S、G、A、I、U、H、F和D，其中被归到D类别中的HcbZIP基因数量最多共有35个，数量最少的为C类别仅有4个，没有HcbZIP基因被归类到E和B类别中。Motif基序分析发现，motif1（RLLQNRESARRSRLRKKAYVQELESSVAK）高度保守在每个家族成员中均鉴定到且构成了bZIP基因的保守结构域。不同类别下的基因其motif基序构成较为接近，且部分motif基序只存在特定类别的基因中。表达分析发现，在鱼腥草7号药材中表达的HcbZIP基因数量多于鱼腥草6号药材，同时也发现单独在7号药材中表达的HcbZIP基因数量也多于鱼腥草6号药材。共发现6个HcbZIP基因，HcbZIP156、HcbZIP153、HcbZIP147、HcbZIP149、HcbZIP48和HcbZIP127在6号和7号药材中均呈现出较高的表达量。通过比较6号和7号的差异bZIP基因发现，共有96个差异表达HcbZIP基因，并将其分成了2大类，共63个差异基因在7号药材中表达量较高，33个差异基因在6号药材中表达量较高。结论 共筛选出4个基因HcbZIP154、HcbZIP150、HcbZIP26和HcbZIP18作为鱼腥草6号和7号2种材料能够形成适应不同生态条件的候选HcbZIP基因。

Objective To lay a foundation for further study of Houttuynia cordata bZIP gene. Methods Based on the transcriptome data of H. cordata, we identified the HcbZIP family genes and analyzed their physicochemical properties, phylogenetic tree, motif compositions and the expressions in two different ecotype H. cordata. Results A total of 163 HcbZIP genes were identified. The number of amino acids encoding proteins ranged from 115 aa (HcbZIP48 and HcbZIP149) to 703 aa (HcbZIP97). More than 53% of the family members were basic proteins, and more than 84% of the family members were unstable proteins, all members of the family were hydrophilic proteins. In the secondary structure, 161 family members are composed of four parts: alpha helix, extended strand, beta turn and random coil. The ratio of beta turn was the lowest, and the ratio of alpha helix and random coil were the highest. Phylogenetic tree analysis divided these 163 family members into 9 classes, including C, S, G, A, I, U, H, F and D, the largest number was in class D with the number of 35, the lowest number was in classes C with only four, and no HcbZIP genes were classified into classes E and B. Motif composition analysis revealed that motif 1 (RLLQNRESARRSRLRKKA- YVQELESSVAK) was highly conserved in each family member and constitutes a conserved domain of the bZIP gene. The motifs of the genes in different classes were close, and part of the motifs only existed in the genes in specific classes. The expression analysis showed that the number of HcbZIP gene expressed in 7# was more than that in 6#, it was also found that the number of HcbZIP gene only expressed in 7# was more than that in 6#. A total of 6 HcbZIP genes including HcbZIP156, HcbZIP153,HcbZIP147, HcbZIP149, HcbZIP48, and HcbZIP127 were highly expressed in 6# and 7#. By comparing the differentially expressed bZIP genes of 6# and 7#, we found that a total of 96 differentially expressed HcbZIP genes, which were divided into 2 classess, and 63 differentially expressed genes were highly expressed in 7#, the expression level of the other 33 differentially expressed genes were higher in 6#. Conclusion A total of 4 genes, including HcbZIP154, HcbZIP150, HcbZIP26 and HcbZIP18 were selected as candidate genes that can adapt to different ecological conditions for these two materials.

R286.12

四川省科技计划项目（2021YJ0115）；四川省科技计划项目（2020YFN0113）