Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Root hairs are filamentous protuberances from superficial cells of plant roots that are critical for nutrient uptake. Genes encoding ROOT HAIR DEFECTIVE-SIX LIKE (RSL) class I basic helix-loop-helix proteins are expressed in future root hair cells (trichoblasts) of the Arabidopsis thaliana root where they positively regulate root hair cell development. We characterized the function of class I genes in Oryza sativa root development. We show that there are three RSL class I genes in O. sativa and that each is expressed in developing root hair cells. Reduction of RSL class I function results in the development of shorter root hairs than in wild-type. Ectopic overexpression results in the development of ectopic root hair cells. These data suggest that expression of individual RSL class I proteins is sufficient for root hair development in the cereal O. sativa (rice). Therefore RSL class I genes have been conserved since O. sativa and A. thaliana last shared a common ancestor. However, given that RSL class I genes are not sufficient for root hair development in A. thaliana, it suggests that there are differences in the mechanisms repressing RSL class I gene activity between members of the Poaceae and Brassicaceae.

Original publication




Journal article


New Phytol

Publication Date





314 - 323


Arabidopsis thaliana , Oryza sativa , ROOT HAIR DEFECTIVE-SIX LIKE (RSL) class I genes, basic helix-loop-helix transcription factors, rice, root hair, roots, Gene Expression Regulation, Plant, Genes, Plant, Indoleacetic Acids, Morphogenesis, Oryza, Phylogeny, Plant Proteins, Plant Roots, RNA, Messenger