Probable transcription factor required for the initiation of inflorescence trichomes in response to gibberellin (GA) (PubMed:16679458, PubMed:17507408). Mediates the induction of GL1 expression by GA in inflorescence organs and is antagonized in its action by the DELLA repressor GAI. Acts upstream of the trichome initiation regulators GL1 and GL3, and downstream of the GA signaling repressor SPINDLY (SPY) (PubMed:16679458). Does not play a significant role in the cytokinin response (PubMed:17507408). Controls trichome branching through GA signaling (PubMed:22210898, PubMed:23825141). Acts downstream of the key regulator STICHEL (STI) in an endoreduplication-independent pathway (PubMed:22210898). Controls trichome cell division indirectly by acting downstream of a key endoreduplication regulator SIAMESE (SIM) (PubMed:23825141). Expressed in inflorescence meristems, floral meristems and stem epidermis. By gibberellin. Reduced trichome production on cauline leaves, stem internodes and branches, and sepals. Plants over-expressing GIS have delayed shoot maturation and flowering, and a strong production of trichome on the inflorescence.