Transcription factor that seems to regulate organogenesis in postembryonic development. Involved in the regulation of shoot branching by controlling axillary meristem initiation. Functions in association with LAX2 to regulate the process of AM formation. Possesses transactivation activity in yeast (PubMed:21963665). Efficient DNA binding requires dimerization with another bHLH protein (By similarity). Interacts with LAX2 (PubMed:21963665). Expressed in the boundary between the shoot apical meristem (SAM) and the region of new meristem formation. Expressed in growing new meristem. Down-regulated in elongating new meristem. Defects in initiation and/or maintenance of rachis-branches, lateral spikelets and terminal spikelets. Belongs to the bHLH protein family. Contains a degenerate basic motif not likely to bind DNA.