Root hairs are important for the uptake of phosphate and other nutrients from soil as well as water absorption. They represent a potential new model to understand plant biology at the level of a single cell, which is rare since most of the different plant organs are multicellular and are of significant interest owing to their unique properties and functions. These properties include growth by tip expansion. The present project pursues the identification of key genes with roles in protein O-glycosylation that are crucial for root hair cell expansion. Using this system, we aim to follow cellular growth of root hairs of different mutants in the O-glycosylation with a live approach using modern microscopic techniques.