2017-present CEPAMS, Institute of Plant Physiology & Ecology, CAS, Principle Invistigator, Shanghai, China
2010-2017 John Innes Centre, group leader, Norwich, UK
2006-2009 The Noble Institute, Oklahoma, USA，Postdoc
2003-2006 SCPFRC, London, Canada, Postdoc
1998-2003 PhD University of Guelph, Guelph, Canada
1993-1997 MSc University of Western Ontario, London, Canada
1989-1993 BSc Dalhousie University, Halifax, Canada
Our research seeks to uncover the molecular mechanisms underlying symbiotic infection of plants by beneficial microbes. To do this we are studying the processes underlying infection of plant roots by rhizobia and arbuscular mycorrhiza. Rhizobia are N-fixing bacteria that colonize the roots of plants to form an endosymbiosis with legumes in which fixed N is provided to the host plant in specialized organs called nodules. This symbiosis, called nodulation, has evolved from a more ancient interaction that arbuscular mycorrhizal fungi form with most land plants. In order to understand how these microbes are accommodated by the host plant we will identify host components required for the colonization of plant roots and the formation of intracellular infection structures.
The key contributions of our lab include the identification of numerous genes required for infection by rhizobia and arbuscular mycorrhiza. We showed that cytokinin signalling negatively effects rhizobial infection, and both cytokinin and auxin are required for nodule formation (1). One of these genes, VAPYRIN, was the first structural gene identified to be required for infection of both rhizobia and arbuscular mycorrhizal fungi (2). Using VAPYRIN as a marker, we identified a novel subcellular structure which we have named the infectosome, which is associated with the polar growth of rhizobial infection threads. We further used transcriptomics studies to discover that genes associated with cell cycle activation are induced during infection of root hairs by rhizobia (3, 4).
1.Murray JD, Karas BJ, Sato S, Tabata S, Amyot L, and Szczyglowski K (2007). A cytokinin perception mutant colonized by rhizobium in the absence of nodule organogenesis. Science 315:101-104.
2.Murray JD, Muni RRD, Torres-Jerez I, Tang Y, Allen S, Andriankaja M, Li G, Laxmi A, Cheng X, Wen J, Vaughan D, Schultze M, Sun J, Charpentier M, Oldroyd G, Tadege M, Ratet P, Mysore KS, Chen R, Udvardi MK (2011) Vapyrin, a gene essential for intracellular progression of arbuscular mycorrhizal symbiosis, is also essential for infection by rhizobia in the nodule symbiosis of Medicago truncatula. Plant Journal 65:244–252.
3.Breakspear A, Liu C, Roy S, Stacey N, Rogers C, Trick M, Morieri G, Mysore KS, Wen J, Oldroyd GED, Downie JA, and Murray JD (2014) The root hair ‘Infectome’ of Medicago truncatula uncovers changes in cell cycle genes and reveals a requirement for auxin signalling in rhizobial infection. Plant Cell 26:4680-701.
4.Roy S, Robson F, Lilley J, Cheng X, Wen J, Walker S, Sun J, Cousins D, Bone C, Bennett MJ., Downie JA, Swarup R, Oldroyd G, Murray JD. (2017) MtLAX2, an orthologue of the Arabidopsis auxin influx transporter AUX1, is required for nodule organogenesis. 174: 326–338.