basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana protein IAA-leucine resistant 3 (ILR3) and similar proteins
ILR3, also termed AtbHLH105, or EN 133, is a bHLH transcription factor that plays a role in resistance to amide-linked indole-3-acetic acid (IAA) conjugates such as IAA-Leu and IAA-Phe. It may regulate gene expression in response to metal homeostasis changes.