The study investigates the subfunctionalization of duplicated GIGANTEA paralogs in Petunia x hybrida, focusing on PhGI2's role in floral transition. While RNAi silencing of PhGI2 caused mixed vegetative and reproductive phenotypes, CRISPR/Cas9-generated loss‑of‑function alleles showed that PhGI2 specifically promotes flowering without affecting vegetative growth or scent. The findings reveal that PhGI2 is essential for maintaining circadian gene expression dynamics and regulating flowering time, separating vegetative growth from reproductive timing.

The authors compiled and standardized published data on Rubisco dark inhibition for 157 flowering plant species, categorizing them into four inhibition levels and analyzing phylogenetic trends. Their meta‑analysis reveals a complex, uneven distribution of inhibition across taxa, suggesting underlying chloroplast microenvironment drivers and providing a new resource for future photosynthesis improvement efforts.