OsVIPP1 Supports Rice Leaf Chloroplast Development and Is Associated with Seed Metabolic Changes and Yield-Related Traits

Plastid membrane integrity is essential for plant growth, development, and metabolism, yet the functions of vesicle-inducing protein in plastids 1 (VIPP1) throughout the crop life cycle remain unclear. Here, we characterized OsVIPP1 in rice using CRISPR/Cas9 knockout, overexpression, and RNA-interference lines, together with ultrastructural, transcriptomic, metabolomic, and targeted biochemical analyses. osvipp1 knockout seedlings exhibited an albino-lethal phenotype, disorganized thylakoid membranes, disrupted intermembrane connections, and altered expression of chloroplast-encoded genes, supporting an essential role for OsVIPP1 in plastid membrane development. Both overexpression and RNA interference delayed seed germination, reduced plant height, and impaired yield-related traits. Integrated transcriptomic and untargeted metabolomic analyses associated altered OsVIPP1 expression with lipid, carbon, and phytohormone-related pathways. In overexpression seeds, abscisic acid content increased to 1.95 times the wild-type level, accompanied by the accumulation of several fatty acids and soluble sugars, whereas abscisic acid and most fatty acids decreased in RNA-interference seeds. These findings indicate that OsVIPP1 supports thylakoid spatial organization in leaves, whereas altered OsVIPP1 expression is associated with metabolic changes in mature seeds and yield-related phenotypes.