Till date, no systematic study of phosphate transporter (PHT) genes is reported in Capsicum species. For the first time, we report the identification and homology modelling of C. annuum PHT genes (CaPHT) belonging to CaPHT1, CaPHT2, CaPHT3, CaPHT4, CaPHT5 and CaPHO family. Further, gene duplication analysis identified 14 segmental and 5 tandemly duplicated gene pairs. Synteny analysis showed high collinearity of CaPHTs with tomato and potato. The 3D structures of CaPHT genes were highly similar to the reference model suggesting potential functional similarities of PHT genes in Capsicum. Analysis in fruit transcriptomes and validation using quantitative real-time PCR showed differential expressions (DE) of CaPHTs in leaf, stem, root, flower and fruit tissues of C. annuum. During P-stress conditions CaPHT1;3 to CaPHT1;7, CaPHT3;1 to CaPHT3;4 and six members of CaPHO family showed DE patterns between leaf and root tissues. Metabolite profiling of plants grown under P-stress conditions showed significantly (p-value <0.001) higher content of glucose, fructose and erythritol in leaves compared to roots. Furthermore, it was observed that most of the organic acids content in leaf decreased under P-stress. The identified CaPHTs would serve as a resource for further studies of phosphate uptake and homeostasis in Capsicum.

迄今为止，尚未报道辣椒属植物中磷酸盐转运蛋白 (PHT) 基因的系统研究。我们首次报告了属于 CaPHT1、CaPHT2、CaPHT3、CaPHT4、CaPHT5 和 CaPHO 家族的C. annuum PHT 基因 (CaPHT)的鉴定和同源建模。此外，基因重复分析确定了 14 个节段和 5 个串联重复的基因对。同线性分析表明，CaPHTs 与番茄和马铃薯具有高度共线性。CaPHT 基因的 3D 结构与参考模型高度相似，表明辣椒中 PHT 基因的潜在功能相似性. 果实转录组分析和实时定量 PCR 验证表明，CaPHTs 在C. annuum 的叶、茎、根、花和果实组织中的差异表达 (DE) 。在 P 胁迫条件下，CaPHT1;3到CaPHT1;7、CaPHT3;1到CaPHT3;4和 CaPHO 家族的六个成员在叶和根组织之间显示出 DE 模式。在 P 胁迫条件下生长的植物的代谢物分析显示，与根相比，叶子中葡萄糖、果糖和赤藓糖醇的含量显着更高（p 值 <0.001）。此外，观察到叶片中大部分有机酸含量在磷胁迫下降低。已识别的CaPHT将作为进一步研究辣椒中磷酸盐吸收和体内平衡的资源。