Data from: GRF-interacting factor1 regulates shoot architecture and meristem determinacy in maize

Plant architecture results from a balance of indeterminate and determinate
cell fates. Cells with indeterminate fates are located in meristems,
comprising groups of pluripotent cells that produce lateral organs.
Meristematic cells are also found in intercalary stem tissue, which
provides cells for internodes, and at leaf margins to contribute to leaf
width. We identified a maize (Zea mays) mutant that has a defect in
balancing determinacy and indeterminacy. The mutant has narrow leaves and
short internodes, suggesting a reduction in indeterminate cells in the
leaf and stem. In contrast, the mutants fail to control indeterminacy in
shoot meristems. Inflorescence meristems are fasciated, and determinate
axillary meristems become indeterminate. Positional cloning identified
growth regulating factor-interacting factor1 (gif1) as the responsible
gene. gif1 mRNA accumulates in distinct domains of shoot meristems,
consistent with tissues affected by the mutation. We determined which
GROWTH REGULATING FACTORs (GRFs) interact with GIF1 and carried out
RNA-seq analysis. Many genes known to play roles in inflorescence
architecture were differentially expressed in gif1. Chromatin
immunoprecipitation identified some differentially expressed genes as
direct targets of GIF1. The interactions with these diverse direct and
indirect targets help explain the paradoxical phenotypes of maize GIF1.
These results provide insights into the biological functions of gif1.