AUXIN1LIKE

AUXIN1LIKE, also known as AXL, is a plant protein that plays a critical role in the plant hormone auxin's function. Auxin is a key regulator of plant growth and development, involved in processes such as cell elongation, cell division, and root development.

AXL is a member of the auxin influx carrier family and is involved in the regulation of auxin levels in plant cells. It is primarily localized to the plasma membrane of plant cells and functions as a transport protein for auxin. AXL helps regulate the amount of auxin in the cell by allowing it to flow in and out of the cell. This regulation of auxin levels is essential for proper plant development.

Plants that lack AXL function show defects in root development, hypocotyl elongation, and organogenesis. AXL is most closely related to the Arabidopsis thaliana protein AUX1, and the two proteins exhibit significant functional redundancy. While AUX1 and AXL are distinct proteins, they share a high degree of similarity and have overlapping substrate specificities.

Studies have identified several key features of AXL's molecular function. AXL is a single-pass transmembrane protein with a carbohydrate binding domain on its N-terminus and an auxin binding domain on its C-terminus. This unique protein structure allows AXL to interact with both the plasma membrane and the auxin molecule, allowing for its transport.

AXL's role in auxin signaling has important implications for plant growth, development, and overall plant anatomy. The protein is specifically involved in conveying auxin signals from the cell membrane to the nucleus, where it triggers gene expression. Further research is needed to fully understand AXL's function in this complex signaling network.