Related Experiment Video
Updated: May 1, 2026

Characterizing Herbivore Resistance Mechanisms: Spittlebugs on Brachiaria spp. as an Example
Published on: June 19, 2011
A conserved mechanism of bract suppression in the grass family
Clinton J Whipple1, Darren H Hall, Stacy DeBlasio
1Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
Abstract:
Suppression of inflorescence leaf, or bract, growth has evolved multiple times in diverse angiosperm lineages, including the Poaceae and Brassicaceae. Studies of Arabidopsis thaliana mutants have revealed several genes involved in bract suppression, but it is not known if these genes play a similar role in other plants with suppressed bracts. We identified maize (Zea mays) tassel sheath (tsh) mutants, characterized by the loss of bract suppression, that comprise five loci (tsh1-tsh5). We used map-based cloning to identify Tsh1 and found that it encodes a GATA zinc-finger protein, a close homolog of HANABA TARANU (HAN) of Arabidopsis. The bract suppression function of Tsh1 is conserved throughout the grass family, as we demonstrate that the rice (Oryza sativa) NECK LEAF1 (NL1) and barley (Hordeum vulgare) THIRD OUTER GLUME (TRD) genes are orthologous with Tsh1. Interestingly, NL1/Tsh1/TRD expression and function are not conserved with HAN. The existence of paralogous NL1/Tsh1/TRD-like genes in the grasses indicates that the NL1/Tsh1/TRD lineage was created by recent duplications that may have facilitated its neofunctionalization. A comparison with the Arabidopsis genes regulating bract suppression further supports the hypothesis that the convergent evolution of bract suppression in the Poaceae involved recruitment of a distinct genetic pathway.
More Related Videos
Related Concept Videos
C4 Pathway and CAM
C4 Pathway
The C4 pathway is used by plants such as...
Regulation of Transpiration by Stomata
Adaptations that Reduce Water Loss
Cell Signaling in Plants
Repressible Operon: trp Operon
Gene Regulation During Sporulation

