College of Agronomy, Xinjiang Agricultural University, Urumqi 830052, China.
Genes (Basel). 2019 Sep 19;10(9):726. doi: 10.3390/genes10090726.
Two class I family teosinte branched1/cycloidea/proliferating cell factor1 (TCP) proteins from allotetraploid cotton are involved in cotton fiber cell differentiation and elongation and root hair development. However, the biological function of most class II TCP proteins is unclear. This study sought to reveal the characteristics and functions of the sea-island cotton class II TCP gene by biochemical, genetic, and molecular biology methods. GbTCP4 protein localizes to nuclei, binding two types of TCP-binding -acting elements, including the one in its promoter. Expression pattern analysis revealed that is widely expressed in tissues, with the highest level in flowers. is expressed at different fiber development stages and has high transcription in fibers beginning at 5 days post anthesis (DPA). overexpression increases primary root hair length and density and leaf and stem trichomes in transgenic relative to wild-type plants (WT). GbTCP4 binds directly to the () promoter, increasing transcript levels in roots and reducing them in leaves. Compared with WT plants, lignin content in the stems of transgenic overexpressing increased, and gene transcript levels increased. These results suggest that GbTCP4 regulates trichome formation and root hair development in and may be a candidate gene for regulating cotton fiber elongation.
两个来自四倍体棉花的 I 类分支/环化酶/增殖细胞因子 1（TCP）蛋白家族成员参与棉花纤维细胞的分化和伸长以及根毛的发育。然而，大多数 II 类 TCP 蛋白的生物学功能尚不清楚。本研究采用生物化学、遗传和分子生物学方法，旨在揭示海岛棉 II 类 TCP 基因的特征和功能。GbTCP4 蛋白定位于细胞核，与两种类型的 TCP 结合作用元件结合，包括其启动子中的元件。表达模式分析表明， 在组织中广泛表达，在花中表达量最高。在纤维发育的不同阶段表达，在开花后 5 天（DPA）开始的纤维中转录水平较高。与野生型植物（WT）相比，过表达 增加了转基因 中主根毛的长度和密度以及叶片和茎的毛状体。GbTCP4 直接与 （）启动子结合，增加了根中的 转录水平，并降低了叶片中的转录水平。与 WT 植物相比，过表达 的转基因 茎中的木质素含量增加， 基因的转录水平也增加。这些结果表明，GbTCP4 调控 和毛状体的形成以及根毛的发育，可能是调控棉花纤维伸长的候选基因。
