AUTHOR=Lin Qingfang , Gong Jiaxin , Zhang Zhiliang , Meng Zizi , Wang Jianyong , Wang Song , Sun Jing , Gu Xu , Jin Yuting , Wu Tong , yan Nuo , Wang Yuxin , Kai Lei , Jiang Jihong , Qi Shilian 

TITLE=The Arabidopsis thaliana trehalose-6-phosphate phosphatase gene AtTPPI regulates primary root growth and lateral root elongation

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.1088278

DOI=10.3389/fpls.2022.1088278

ISSN=1664-462X

ABSTRACT=<p>Roots are the main organs through which plants absorb water and nutrients. As the key phytohormone involved in root growth, auxin functions in plant environmental responses by modulating auxin synthesis, distribution and polar transport. The <italic>Arabidopsis thaliana trehalose-6-phosphate phosphatase</italic> gene <italic>AtTPPI</italic> can improve root architecture, and <italic>tppi1</italic> mutants have significantly shortened primary roots. However, the mechanism underlying the short roots of the <italic>tppi1</italic> mutant and the upstream signaling pathway and downstream genes regulated by <italic>AtTPPI</italic> are unclear. Here, we demonstrated that the <italic>AtTPPI</italic> gene could promote auxin accumulation in <italic>AtTPPI</italic>-overexpressing plants. By comparing the transcriptomic data of <italic>tppi1</italic> and wild-type roots, we found several upregulations of auxin-related genes, including <italic>GH3.3</italic>, <italic>GH3.9</italic> and <italic>GH3.12</italic>, may play an important role in the <italic>AtTPPI</italic> gene-mediated auxin transport signaling pathway, ultimately leading to changes in auxin content and primary root length. Moreover, increased <italic>AtTPPI</italic> expression can regulate primary root growth and lateral root elongation under different concentration of nitrate conditions. Overall, constitutive expression of <italic>AtTPPI</italic> increased auxin contents and improved lateral root elongation, constituting a new method for improving the nitrogen utilization efficiency of plants.</p>