IBA Transport by PDR Proteins

Indole-3-butyric acid (IBA) is an important contributor to auxin homeostasis and blocking IBA conversion to the active auxin indole-3-acetic acid (IAA) results in an array of developmental defects. Similar to IAA, IBA movement within the plant is mediated by carriers, many of which remain unidentified. In this chapter, we discuss roles for IBA in plant development, roles for PLEIOTROPIC DRUG RESISTANCE (PDR) members of the ABCG family in IBA transport, and missing transporters required for IBA movement.