The Target of Rapamycin Complex 1 (TORC1) involved in coordination of cell growth and metabolism is highly conserved among eukaryotes. Yet the signals and mechanisms controlling its activity differ among taxa, according to their biological specificities. A common feature of fungal and plant cells, distinguishing them from animal cells, is that their plasma membrane contains a highly abundant H⁺-ATPase which establishes an electrochemical H⁺ gradient driving active nutrient transport. We have previously reported that in yeast, nutrient-uptake-coupled H⁺ influx elicits transient TORC1 activation and that the plasma-membrane H⁺-ATPase Pma1 plays an important role in this activation, involving more than just establishment of the H⁺ gradient. We show here that the PMA2 H⁺-ATPase from the plant Nicotiana plumbaginifolia can substitute for Pma1 in yeast, to promote H⁺-elicited TORC1 activation. This H⁺-ATPase is highly similar to Pma1 but has a longer carboxy-terminal tail binding 14–3–3 proteins. We report that a C-terminally truncated PMA2, which remains fully active, fails to promote H⁺-elicited TORC1 activation. Activation is also impaired when binding of PMA2 to 14–3–3 s is hindered. Our results show that at least some plant plasma-membrane H⁺-ATPases share with yeast Pma1 the ability to promote TORC1 activation in yeast upon H⁺-coupled nutrient uptake.

参与协调细胞生长和代谢的雷帕霉素复合物 1 (TORC1) 的靶标在真核生物中高度保守。然而，根据其生物学特性，控制其活动的信号和机制因分类群而异。真菌和植物细胞的一个共同特征是它们与动物细胞的区别，它们的质膜含有高度丰富的 H ⁺ -ATPase，它建立了一个电化学 H ⁺梯度，驱动了主动的营养物质运输。我们之前曾报道过，在酵母中，养分吸收耦合的 H ⁺流入引发瞬时 TORC1 激活，质膜 H ⁺ -ATPase Pma1 在此激活中起重要作用，涉及的不仅仅是H ^{+ 的}建立⁺渐变。我们在这里展示了来自植物Nicotiana plumbaginifolia的 PMA2 H ⁺ -ATPase可以替代酵母中的 Pma1，以促进 H ⁺引发的 TORC1 激活。这种 H ⁺ -ATPase 与 Pma1 高度相似，但具有更长的羧基末端尾结合 14-3-3 蛋白质。我们报告说，一个 C 端截断的 PMA2 仍然完全活跃，但不能促进 H ⁺引发的 TORC1 激活。当 PMA2 与 14-3-3 s 的结合受阻时，激活也会受损。我们的结果表明，在至少一些植物等离子体膜H ⁺ -ATP酶与酵母PMA1份额促进TORC1激活时ħ酵母的能力⁺ -偶联的养分吸收。