How do auxins promote the growth of a tendril around a support?

Auxins are the plant hormones present at the tip of tendrils.Growth of tendrils slow down if they are attached around any support because auxins are sensitive to touch. This makes them move to the other side of the tip to get support and results in making the other side grow faster than the side of tendril in contact with the support and the tendril bends towards the support.