Key message

TPST is involved in fructose signaling to regulate the root development and expression of genes in biological processes including auxin biosynthesis and accumulation in Arabidopsis.

Abstract

Sulfonation of proteins by tyrosine protein sulfotransferases (TPST) has been implicated in many important biological processes in eukaryotic organisms. Arabidopsis possesses a single TPST gene and its role in auxin homeostasis and root development has been reported. Here we show that the Arabidopsis tpst mutants are hypersensitive to fructose. In contrast to sucrose and glucose, fructose represses primary root growth of various ecotypes of Arabidopsis at low concentrations. RNA-seq analysis identified 636 differentially expressed genes (DEGs) in Col-0 seedlings in response to fructose verses glucose. GO and KEGG analyses of the DEGs revealed that fructose down-regulates genes involved in photosynthesis, glucosinolate biosynthesis and IAA biosynthesis, but up-regulates genes involved in the degradation of branched amino acids, sucrose starvation response, and dark response. The fructose responsive DEGs in the tpst mutant largely overlapped with that in Col-0, and most DEGs in tpst displayed larger changes than in Col-0. Interestingly, the fructose up-regulated DEGs includes genes encoding two AtTPST substrate proteins, Phytosulfokine 2 (PSK2) and Root Meristem Growth Factor 7 (RGF7). Synthesized peptides of PSK-α and RGF7 could restore the fructose hypersensitivity of tpst mutant plants. Furthermore, auxin distribution and accumulation at the root tip were affected by fructose and the tpst mutation. Our findings suggest that fructose serves as a signal to regulate the expression of genes involved in various biological processes including auxin biosynthesis and accumulation, and that modulation of auxin accumulation and distribution in roots by fructose might be partly mediated by the TPST substrate genes PSK-α and RGF7.

中文翻译：

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TPST 参与拟南芥初生根生长的果糖调控。

关键信息

TPST参与果糖信号传导，以调节拟南芥中生长素生物合成和积累等生物过程中的根发育和基因表达。

抽象的

酪氨酸蛋白磺基转移酶 (TPST) 对蛋白质的磺化与真核生物的许多重要生物学过程有关。拟南芥拥有一个单一的TPST基因，其在生长素稳态和根发育中的作用已有报道。在这里，我们表明拟南芥tpst突变体对果糖过敏。与蔗糖和葡萄糖相比，果糖在低浓度下抑制各种生态型拟南芥的初生根生长。RNA-seq 分析在 Col-0 幼苗中鉴定出 636 个差异表达基因 (DEG)，以响应果糖和葡萄糖。DEG 的 GO 和 KEGG 分析表明，果糖下调参与光合作用、硫代葡萄糖苷生物合成和 IAA 生物合成的基因，但上调参与支链氨基酸降解、蔗糖饥饿反应和暗反应的基因。tpst突变体中果糖响应的 DEGs与 Col-0 中的大部分重叠，并且tpst中的大多数 DEGs显示出比 Col-0 更大的变化。有趣的是，果糖上调的 DEG 包括编码两种 AtTPST 底物蛋白的基因，即植物硫素 2 ( PSK2 ) 和根分生组织生长因子 7 ( RGF7 )。PSK-α和RGF7的合成肽可以恢复tpst突变植物的果糖超敏反应。此外，根尖的生长素分布和积累受果糖和tpst的影响。突变。我们的研究结果表明，果糖可作为调节参与各种生物过程（包括生长素生物合成和积累）的基因表达的信号，并且果糖对生长素在根中积累和分布的调节可能部分由 TPST 底物基因 PSK-α 介导。和 RGF7。