Lei Jiaming, Xu Chan, Li Rui, Chen Xiaoyan, Fu Zhengyang, Yao Juanni, Li Zhengguo, Cheng Yulin
Key Laboratory of Plant Hormones and Molecular Breeding of Chongqing, School of Life Sciences, Chongqing University, Chongqing, 401331, China; Center of Plant Functional Genomics and Synthetic Biology, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, 401331, China.
Key Laboratory of Plant Hormones and Molecular Breeding of Chongqing, School of Life Sciences, Chongqing University, Chongqing, 401331, China; Center of Plant Functional Genomics and Synthetic Biology, Institute of Advanced Interdisciplinary Studies, Chongqing University, Chongqing, 401331, China.
Plant Physiol Biochem. 2025 May;222:109731. doi: 10.1016/j.plaphy.2025.109731. Epub 2025 Mar 3.
Remorins (REMs) are plant-specific proteins associated with plasma membrane (PM) and exhibit diverse biological functions. However, the roles of remorins in fruit crops and fruit disease resistance remain unexplored. Here, we performed a genome-wide characterization of remorin genes from citrus (Citrus sinensis) and identified an atypical remorin CsREM1.1 responsible for fruit resistance to Penicillium digitatum (Pd), a notorious postharvest fungal pathogen of citrus. Ten remorin genes were identified in the C. sinensis genome and they were categorized into five groups. A lot of cis-elements involved in hormone and stress responsiveness were exhibited in the promoter regions of citrus remorin genes. Reverse transcription-quantitative PCR (RT-qPCR) analysis showed that the majority of citrus remorin genes, especially CsREM1.1, were significantly induced in citrus fruit upon Pd infection. Unlike typical remorins, CsREM1.1 exhibited nuclear localization in addition to its traditional PM localization. Transient expression of CsREM1.1 in the model plant Nicotiana benthamiana suppressed plant cell death triggered by BAX, an important pro-apoptotic factor, and enhanced plant resistance to Botrytis cinerea. Moreover, transient overexpression or silencing of CsREM1.1 in citrus fruit indicated the important contribution of CsREM1.1 in fruit resistance to Pd. Our study increases the understanding of plant remorins and provides valuable insights for future research on fruit disease resistance.
Remorins（REM）是与质膜（PM）相关的植物特异性蛋白，具有多种生物学功能。然而，remorins在果树作物和果实抗病性中的作用仍未得到探索。在此，我们对柑橘（Citrus sinensis）中的remorin基因进行了全基因组鉴定，并鉴定出一种非典型的remorin CsREM1.1，它负责果实对指状青霉（Pd）的抗性，指状青霉是柑橘一种臭名昭著的采后真菌病原体。在甜橙基因组中鉴定出10个remorin基因，并将它们分为5组。柑橘remorin基因的启动子区域显示出许多参与激素和胁迫响应的顺式元件。逆转录定量PCR（RT-qPCR）分析表明，大多数柑橘remorin基因，尤其是CsREM1.1，在柑橘果实受到Pd感染后被显著诱导。与典型的remorins不同，CsREM1.1除了其传统的质膜定位外，还表现出核定位。CsREM1.1在模式植物本氏烟草中的瞬时表达抑制了由重要的促凋亡因子BAX触发的植物细胞死亡，并增强了植物对灰霉病的抗性。此外，CsREM1.1在柑橘果实中的瞬时过表达或沉默表明CsREM1.1在果实对Pd的抗性中起重要作用。我们的研究增进了对植物remorins的理解，并为未来果实抗病性研究提供了有价值的见解。
