Properties of INDETERMINATE DOMAIN Proteins from : DNA-Binding, Interaction with GRAS Proteins, and Transcriptional Activity.

INDETERMINATE DOMAIN (IDD) proteins are plant-specific transcription factors that interact with GRAS proteins, such as DELLA and SHORT ROOT (SHR), to regulate target genes. The combination of IDD and DELLA proteins regulates genes involved in gibberellic acid (GA) synthesis and GA signaling, whereas the combination of IDD with the complex of SHR and SCARECROW, another GRAS protein, regulates genes involved in root tissue formation. Previous bioinformatic research identified seven , two , and two genes in , a model organism for non-vascular plants (bryophytes), which lack a GA signaling pathway and roots.