Auxin plays a crucial role in lateral root development. In this issue, Cui et al. (pp. 496–505) report in rice that OsZFP as a C2HCtype zinc finger protein participates in IAA signal pathways to control lateral root development by interacting with cyclophilin. The expression of Aux/IAA genes (OsIAA1, 8, 11, 23, 31) was altered in OsZFP-RNAi lines in response to IAA treatments.