May be involved in the regulation of ethylene receptor signaling. Promotes cell expansion and plant growth. Plants silencing SAUR78 exhibit increased sensitivity to ethylene, while plants over-expressing SAUR78 display reduced ethylene sensitivity. Plants over-expressing SAUR78 exhibit increased rosette diameters. Belongs to the ARG7 family. The article by Li et al was retracted by the editors after publication. Concerns were raised regarding a number of figure panels, such as partial overlap between the panels and duplication of protein gel analysis.