Magdalen College

E-mail:
  liam.dolan@plants.ox.ac.uk

Tel  +44 (0)1865 275147
Fax +44 (0)1865 275047

Last Modified: February 2013

The general aim of our research is to understand general principles of cell development and evolution using specialized rooting cells such as rhizoids and root hairs as models. The main activities in the lab fall into five overlapping areas.

Developmental genetics of the Arabidopsis root epidermis

The Arabidopsis root epidermis comprises a patterned array of hair and non hair cells. We use a combination of computational and genetic approaches to investigate how epidermal pattern develops in the embryo and seedling meristems. We discovered that once pattern is established, the RSL group of basic helix loop helix transcription factors positively regulates the differentiation of root hairs. Class 1 RSL proteins control early stages of development such as root hair initiation while Class 2 RSL proteins control later stages when the root hair grows out into the soil.

Stem cell regulation in Arabidopsis roots

The tissues of the root are derived from a population of stem cells at the tip of the root. The transcriptional regulator SCZ controls the early development of groups of stem cells in the embryo and their subsequent activity in seedlings. We are defining the mechanism by which SCZ controls tissue formation through its activity in stem cells.

Genetic basis of rooting system evolution

The first land plants had filamentous rooting systems as exemplified by extant liverworts and mosses. The RSL family of basic loop helix transcription factors controls the development of these rooting systems as well as the formation of root hairs in derived groups of land plants such as the seed plants. We are currently using a combination of genetic and computational methods to define how the RSL networks have diverged over the last 443 million years since bryophtyes and seed plants last shared a common ancestor.

Enhancement of nutrient uptake in crops

Root hairs are important for the uptake of phosphate from the soil especially in heavily weathered and acidic soils. Using knowledge gained from model systems, we are investigating the regulation of root hair initiation and growth in rice, wheat and brassica crops. The long-term aim is to provide germplasm to breeders who can then develop crops with enhanced nutrient uptake capability. It is anticipated that such cultivars would require less phosphate application in fertilizers. Consequently their cultivation could contribute to the reduction in the amounts of phosphate fertilizer that are applied to fields and that runoff into water systems as pollutants.

Selected publications since 2003

Pernas-Ochoa M, Ryan E, Dolan L 2010 SCHIZORHIZA controls tissue system complexity in plants. Current Biology 20, 818-823

Keke Y, Bell E, Menand B, Dolan L 2010 A basic helix loop helix transcription factor controls cell growth and size in root hairs Nature Genetics 42, 264-267

Pires N and Dolan L 2010 Origin and diversification of basic helix-loop helix proteins in plants. Molecular Biology and Evolution 27, 862-874

Saint Savage N, Walker T, Panciera Y, Schiefelbein J, Dolan L, Monk NAM 2008 Mutual support of alternative cell fates through the directed movement of CAPRICE and GLABRA3 provides a novel mechanism for patterning the Arabidopsis root epidermis PLoS Biology 6, e235

Takeda S, Gapper C, Kaya H, Bell E, Kuchitsu K, Dolan L 2008 Local positive feedback regulation determines cell shape in root hair cells Science 319, 1241-1243

Ortega-Martinez O, Pernas-Ochoa M, Carol R, Dolan L 2007 Ethylene modulates stem cells division in the Arabidopsis thaliana root. Science 317, 505-510

Menand B, Keke Y, Jouannic S, Hoffmann L, Ryan E, Linstead P, Schaefer DG, Dolan L 2007 An ancient mechanism controls the development of cells with a rooting function in land plants Science 316, 1477-1480

Menand B, Calder G, Dolan L. 2007 Chloronema and caulonema expand by tip growth in the Moss Physcomitrella patens Journal of Experimental Botany 58, 1843-1849

Kim C M, Park S H, Je B I, Park S H, Park S J, X, Piao H L, Eun M Y, Dolan L, Han C 2007 OsCSLD1, a cellulose synthase-like D1 gene, is required for root hair morphogenesis in rice (Oryza sativa L.) Plant Physiology 143, 1220-30

Carol RJ, Takeda S, Linstead P, Durrant MC, Kakesova H, Derbyshire P, Drea S, Zarsky V, Dolan L 2005 A RhoGDP dissociation inhibitor spatially regulates growth in root hair cells Nature 438, 1013-1016

Costa S, Dolan L 2003 Epidermal patterning genes are active during embryogenesis in Arabidopsis Development 130, 2893-2901

Foreman J, Demedchik V, Bothwell J, Mylona J, Vadema H, Torres M, Costa S, Brownlee C, Jones JDG, Davies J, Dolan L 2003 RHD2 is an NADPH oxidase that regulates plant cell growth Nature 422, 442-445

Full Publication List (while at this department)

Dolan, L. (2013) Pointing PINs in the right directions: A potassium transporter is required for the polar localization of auxin efflux carriers New Phytologist. 197 (4): pp 1027-1028.
doi:10.1111/nph.12151.

Lenton, T.M, Crouch, M, Johnson, M, Pires, N, Dolan, L. (2012) First plants cooled the Ordovician Nature Geoscience. 5 (2): pp 86-89.
doi:10.1038/ngeo1390.

Pires, N.D, Dolan, L. (2012) Morphological evolution in land plants: New designs with old genes Philosophical Transactions of the Royal Society B: Biological Sciences. 367 (1588): pp 508-518.
doi:10.1098/rstb.2011.0252.

Datta, S, Kim, C.M, Pernas, M, Pires, N.D, Proust, H, Tam, T, Vijayakumar, P, Dolan, L. (2011) Root hairs: development, growth and evolution at the plant-soil interface Plant and Soil. pp 1-14.
doi:10.1007/s11104-011-0845-4.

Jang, G, Dolan, L. (2011) Auxin promotes the transition from chloronema to caulonema in moss protonema by positively regulating PpRSL1and PpRSL2 in Physcomitrella patens New Phytologist..
doi:10.1111/j.1469-8137.2011.03805.x.

Jang, G, Yi, K, Pires, N.D, Menand, B, Dolan, L. (2011) RSL genes are sufficient for rhizoid system development in early diverging land plants Development. 138 (11): pp 2273-2281.
doi:10.1242/dev.060582.

Kim, C.M, Dolan, L. (2011) Root hair development involves asymmetric cell division in Brachypodium distachyon and symmetric division in Oryza sativa New Phytologist..
doi:10.1111/j.1469-8137.2011.03839.x.

Pires, N, Dolan, L. (2010) Early evolution of bHLH proteins in plants Plant Signaling and Behavior. 5 (7): pp 911-912.
doi:10.1093/molbev/msp288.

Yi, K, Menand, B, Bell, E, Dolan, L. (2010) A basic helix-loop-helix transcription factor controls cell growth and size in root hairs Nature Genetics. 42 (3): pp 264-267.
doi:10.1038/ng.529.

Dolan, L, Langdale, J.A. (2004) New insights into plant development in New England Development. 131 (21): pp 5215-5220.
doi:10.1242/dev.01439.

• Nick Monk, University of Nottingham, UK
• Richard Morris, John Innes Centre, Norwich, UK
• Peter Shaw, John Innes Centre, Norwich, UK
• Mary Byrne, University of Sydney, Australia
• John Snape and Philipe Vain, John Innes Centre, UK