A method for the isolation of root hairs from the model legume Medicago truncatula

A new method for the isolation of root hairs from the model legume, Medicago truncatula, was developed. The procedure involves the propagation of detached roots on agar plates and the collection of root hairs by immersion in liquid nitrogen. Yields of up to 40 micro g of root hair protein were obtained from 50-100 root tips grown for 3 weeks on a single plate. The high purity of the root hair fraction was monitored by western blot analysis using an antibody to the pea epidermis specific protein PsRH2. Sequence analyses revealed that the protein homologous to PsRH2 in M. truncatula, MtRH2, is identical to the root protein MtPR10-1. The MtRH2 protein proved to be a useful endogenous marker to monitor root hair isolation since it is also specifically expressed in the root epidermis.