The <i>IRE</i> gene encodes a protein kinase homologue and modulates root hair growth in <i>Arabidopsis</i>

The study explored the role of the IRE gene in Arabidopsis, revealing that it encoded a protein kinase homologue crucial for normal root hair elongation. The ire mutant had root hairs 60% the length of the wild type, indicating a specific inhibition of root hair growth. The mutation was recessive and linked to a single genetic locus. The IRE gene interacted with the HY5 gene, suggesting both were involved in controlling root hair growth duration. The IRE gene was expressed in all plant organs, with higher levels in roots, and its expression was linked to root hair development. The study suggested that IRE might be part of a hormone-signaling pathway and identified IREH1, a homologue with potential broader functions in root growth. Despite these findings, the exact function of IRE remained unclear.