The study characterizes the distinct and overlapping roles of the rice PI paralogs OsMADS2 and OsMADS4 in lodicule specification, flowering time, and floral organ development by analyzing null and double mutants and overexpression lines. Genome-wide binding (ChIP‑seq) and transcriptome (RNA‑seq) analyses identified downstream targets involved in cell division, cell wall remodeling, and osmotic regulation that underpin the observed phenotypes. These findings reveal novel functions for PI paralogs in reproductive development and highlight mechanisms of transcription factor diversification in Oryza sativa.

The study examined transposable element (TE) silencing in the duckweed Spirodela polyrhiza, which exhibits unusually low DNA methylation, scarce 24‑nt siRNAs, and missing RdDM components. While degenerated TEs lack DNA methylation and H3K9me2, they retain heterochromatin marks H3K9me1 and H3K27me1, whereas the few intact TEs show high DNA methylation and H3K9me2, indicating a shift in RdDM focus toward potentially active TEs and suggesting heterochromatin can be maintained independently of DNA methylation in flowering plants.