Li Yimei, Wang Jiao, Liang Xiao, Wu Shurong, Zhang Jie, Wu Changqi, Wang Anran, Fang Hanmo, Ding Shuting, Yu Jingquan, Wu Shuang, Liu Huan, Shi Kai
Department of Horticulture, Zhejiang University, Hangzhou 310058, China.
Department of Horticulture, Zhejiang University, Hangzhou 310058, China; Hainan Institute, Zhejiang University, Sanya 572025, China.
Mol Plant. 2025 Jun 2;18(6):1014-1028. doi: 10.1016/j.molp.2025.05.002. Epub 2025 May 6.
Prolonged exposure to low temperatures during agricultural production often leads to fruit malformation in crops, significantly reducing market value. However, the underlying molecular mechanisms remain poorly understood. In this study, we identify sugar transport protein 2 (STP2) as a critical regulator of tomato fruit locule development under cold conditions. Low temperatures impair long-distance sucrose transport from leaves to shoot apices, resulting in reduced accumulation of glucose and arabinose. In response, STP2 expression is strongly upregulated in shoot apices, promoting glucose and arabinose transport. We found that the CLAVAT3-WUSCHEL (CLV3-WUS) regulatory module, which governs locule formation, relies on STP2-mediated sugar transport for CLV3 arabinosylation. Overexpression of STP2 promotes glucose and arabinose accumulation in shoot apices, enhances CLV3 arabinosylation and the WUS suppression, mitigating the multi-locular malformations induced by low temperatures. Conversely, disruption of STP2 function exacerbates locule number increases under low temperatures, which could not be rescued by exogenous sugar supplementation. Our findings reveal a key mechanism by which STP2-mediated sugar transport supports CLV3 arabinosylation to maintain fruit locule development under low temperatures, offering potential strategies to alleviate fruit malformations in winter crop cultivation.
在农业生产过程中，长时间暴露于低温环境常常导致作物果实畸形，显著降低其市场价值。然而，其潜在的分子机制仍知之甚少。在本研究中，我们确定糖转运蛋白2（STP2）是低温条件下番茄果实心室发育的关键调节因子。低温会损害蔗糖从叶片到茎尖的长距离运输，导致葡萄糖和阿拉伯糖的积累减少。作为响应，STP2在茎尖的表达强烈上调，促进葡萄糖和阿拉伯糖的运输。我们发现，控制心室形成的CLAVAT3-WUSCHEL（CLV3-WUS）调控模块依赖于STP2介导的糖运输来进行CLV3的阿拉伯糖基化。STP2的过表达促进了茎尖中葡萄糖和阿拉伯糖的积累，增强了CLV3的阿拉伯糖基化以及WUS的抑制作用，减轻了低温诱导的多心室畸形。相反，STP2功能的破坏会加剧低温下心室数量的增加，而外源糖补充无法挽救这种情况。我们的研究结果揭示了一种关键机制，即STP2介导的糖运输支持CLV3的阿拉伯糖基化，以在低温下维持果实心室发育，为减轻冬季作物栽培中的果实畸形提供了潜在策略。
