叶绿体介导的抗病毒防御和病毒反防御研究进展
摘要
<sec><p indent="0mm">As one of the most dynamic organelles, chloroplast not only carries out photosynthesis to convert light into chemical energy to sustain plant life activities but also plays a central role in phytohormone biosynthesis, including salicylic acid (SA), jasmonic acid (JA), abscisic acid (ABA). Additionally, they are key sites for reactive oxygen species (ROS) production, which are critical for antiviral defense responses and the transportation of signaling molecules. However, the host internal environment is manipulated and reorganized during plant virus infection. As the first prime target, the structure and functions of the chloroplast are often destroyed during plant virus infection. </sec><sec> Increasing evidence highlights the dual roles of chloroplasts in plant-virus interactions. Chloroplast-mediated immunity has emerged as a pivotal mechanism for coordinating plant defense responses during pattern-triggered immunity (PTI) and effector-triggered immunity (ETI), which are induced by bacterial invasion and virus infection. During plant pathogen invasion, chloroplasts produce and release pro-defense signals, including phytohormones SA and JA, ROS, and cytoplasmic Ca<sup>2+</sup>. Recent studies have further revealed the connections between chloroplasts and plasma membranes or nuclei. The stromules derived from the chloroplast membrane and stroma are induced during cell death and viral infection, mediating retrograde signaling to the nucleus, thus directing the chloroplast perinuclear clustering, that directly or indirectly involves the plant defense immunity. </sec><sec> Conversely, viruses exploit chloroplast factors to sustain their replication and infection. Some viruses disrupt the redox homeostasis and reorganize the chloroplast membranes to establish their replication factories or recruit chloroplast-localized proteins to viral replication sites to facilitate replication or movement. Moreover, to counteract the chloroplast-mediated defense