hormone-biology
Hormone biology in plants examines the biosynthesis, signaling, and regulatory roles of chemical messengers such as auxins, gibberellins, cytokinins, abscisic acid, and ethylene. These hormones orchestrate virtually every aspect of plant development and stress response, from seed germination and root growth to flowering and fruit ripening. Understanding plant hormone networks is essential for decoding how plants adapt to environmental challenges and for developing targeted strategies in agriculture and crop improvement.
open_in_new WikipediaPubMed · 2026-05-07
Scientists discovered that a family of proteins called TCP transcription factors acts as a molecular bridge, guiding a key hormone signaling repressor (SMXL6) to the right spots on plant DNA so that strigolactone hormones can properly control branching and plant height.
TCP4 shows the highest chromatin co-localization frequency with SMXL6 out of 108 transcription factors screened, co-localizing at promoters of 18 strigolactone-induced target genes including BRC1.
Loss of CIN-TCP function (tcp3/4/10 mutants) reduced hormone responsiveness of strigolactone-induced genes and, when introduced into strigolactone-deficient mutants, restored BRC1 expression above wild-type levels — yet only partially rescued the excess-branching phenotype, indicating BRC1 is not the sole branching regulator.
The tcp3/4/10 triple mutation unexpectedly rescued the dwarf phenotype of strigolactone-deficient mutants, revealing a novel TCP-dependent mechanism underlying strigolactone-regulated plant height.
