PubMed · 2026-05-27
Scientists discovered a three-gene switch (GhOFP1-GhTALE-GhXTHB) that controls how cotton stems grow thicker by regulating the vascular cambium — the ring of cells responsible for adding new wood each season. Manipulating these genes can either expand or shrink the cambium layer, opening a path to engineering stronger, woodier, or higher-biomass cotton plants.
Overexpressing GhXTHB reduced vascular cambium cell layers and xylem width, while knocking it out with CRISPR increased cambium layers without affecting xylem width.
GhTALE acts as a negative regulator of GhXTHB — plants with edited GhTALE showed increased GhXTHB expression — and GhTALE overexpression itself promoted cambium cell proliferation and more cambial layers.
GhOFP1 physically interacts with GhTALE and is recruited to the GhXTHB promoter, establishing a three-component transcriptional cascade (GhOFP1→GhTALE→GhXTHB) governing radial stem growth.
