2014 Goldacre recipient Dr Brett Ferguson
Brett Ferguson grew up in Stratford, Ontario, Canada. He attended the nearby University of Waterloo where he obtained a Bachelor of Science degree (Hon). It was during his undergraduate degree that Brett became interested in the nitrogen fixing symbiosis between legume plants and rhizobia bacteria. He pursued this interest by undertaking a research-based Masters of Science at Wilfred Laurier University and the University of Waterloo under the supervision of Prof. Frederique Guinel. Brett’s MSc project used mutant plants and a variety of techniques, including hormone quantification studies, to enhance the understanding of plant hormones in pea nodulation. Indeed, he identified novel roles for ethylene and cytokinin, including demonstrating that elevated cytokinin levels can increase ethylene biosynthesis, leading to an inhibition of nodulation (Ferguson et al. 2005a). These, and other related findings, together with his subsequent proposal to establish nodulation research at the University of Tasmania (UTAS), resulted in Brett being awarded a number of scholarships to undertake a PhD at UTAS under the supervision of Prof. James Reid and A/Prof. John Ross.
During his PhD, Brett developed the novel approach of using well-characterised mutant plants to investigate legume nodulation. This resulted in the first demonstration of a requirement for brassinosteroid hormones in nodulation (Ferguson et al. 2005b). Moreover, it established a central role for gibberellin hormones in nodule development (Ferguson et al. 2005b; Ferguson et al. 2011). This included identifying a novel interaction between gibberellins and ethylene, where too much, or too little, gibberellin leads to an increase in ethylene biosynthesis (Ferguson et al. 2011). His research studies also provided important new insight into developmental overlaps existing between roots and nodules using the homeotic mutant of pea, cochleata (Ferguson and Reid 2005).
Brett was recruited to join the ARC Centre of Excellence for Integrative Legume Research (CILR) during his PhD. When his studies were complete, he moved up to Brisbane to undertake a postdoctoral position at the UQ node of the CILR with Prof. Christine Beveridge. This work focused on understanding the signalling interactions involved in the regulatory control of shoot branching. He developed the novel technique of stem girdling as a tool to study the transport of auxin and other long-distance signals involved in shoot branching, such as mobile plant resources (Ferguson and Beveridge 2009). Additional work investigating the role of auxin, cytokinin and strigolactones has also contributed to the physiological and molecular understanding of shoot branching (e.g., Dun et al. 2006; Dodd et al. 2008; Ferguson and Beveridge 2009; Brewer et al. 2009; Renton et al. 2012; Young et al. 2014).
Brett was subsequently recruited to join the research group of Prof. Peter Gresshoff in the CILR, where he has aided in the discovery of many new genes, signals and signalling interactions required for the formation and regulation of soybean nodules. This work predominately formed the basis for his Goldacre Award. He helped to identify a number of novel, differentially-regulated genes acting in the early stages of nodule development (e.g., Hayashi et al. 2012, 2014; Wang et al. 2014). He also considerably contributed to the discovery and functional characterisation of many new genes and signals acting to regulate legume nodule numbers. The ability to regulate nodule numbers is critical for the plant, as forming nodules is extremely resource-demanding. As a result, legumes have developed innate mechanisms to balance their need to acquire nitrogen with their ability to expend energy. Brett’s findings using soybean and common bean include the discovery of novel, small hormone-like peptide signals that control legume nodule numbers (e.g., Reid et al. 2011a; 2013; Ferguson et al. 2014; reviewed in Hastwell et al. 2015). These discoveries have advanced the molecular model of nodulation control (Ferguson et al. 2010; Reid et al. 2011b) and have resulted in multiple publications, journal covers, patents, grants and speaking invitations.
Through a multi-disciplinary and trans-institutional approach, Brett’s research has helped to contribute to the research fields of legume nodulation, shoot branching, hormone interactions, and peptide signalling in plant development. To find out more about Brett’s work, visit: http://www.uq.edu.au/agriculture/brettferguson or http://www.cilr.uq.edu.au/brett-ferguson.
- Contact Dr. Brett Ferguson
Brewer P, Dun EA, Ferguson BJ, Rameau C, Beveridge CA (2009) Strigolactone acts downstream of auxin to regulate bud outgrowth in pea and Arabidopsis. Plant Physiology 150: 482-493.
Dodd IC, Ferguson BJ, Beveridge CA (2008) Apical wilting and petiole xylem vessel diameter of the rms2 branching mutant of pea are shoot controlled and independent of a long-distance signal regulating branching. Plant and Cell Physiology 49: 791-800.
Dun EA1, Ferguson BJ1, Beveridge CA (2006) Apical dominance and shoot branching. Divergent opinions or divergent mechanisms? Plant Physiology 142: 812-819. (1 authors contributed equally)
Ferguson BJ, Beveridge CA (2009) Roles for auxin, cytokinin, and strigolactone in regulating shoot branching. Plant Physiology 149: 1929-1944.
Ferguson BJ, Foo E, Reid JB, Ross JJ (2011) Relationship between gibberellin, ethylene and nodulation in Pisum sativum. New Phytologist 189: 829-842.
Ferguson BJ, Indrasumunar A, Hayashi S, Lin Y-H, Lin M-H, Reid D, Gresshoff PM (2010) Molecular analysis of legume nodule development and autoregulation. Journal of Integrative Plant Biology 52: 61-76.
Ferguson BJ, Li D, Hastwell AH, Reid DE, Li Y, Jackson S, Gresshoff PM (2014) The soybean (Glycine max) nodulation-suppressive CLE peptide, GmRIC1, functions interspecifically in common white bean (Phaseolus vulgaris), but not in a supernodulating line mutated in PvNARK. Plant Biotechnology Journal 12: 1085-1097.
Ferguson BJ, Reid JB (2005) cochleata: getting to the root of legume nodules. Plant and Cell Physiology 46: 1583-1589.
Ferguson BJ, Reid JB, Ross JJ (2005b) Nodulation phenotypes of gibberellin and brassinosteroid mutants of Pisum sativum. Plant Physiology 138: 2396-2405.
Ferguson BJ, Wiebe EM, Emery RJN, Guinel FC (2005a) Cytokinin accumulation and an altered ethylene response mediate the pleiotropic phenotype of the pea nodulation mutant R50 (sym16). Canadian Journal of Botany 83: 989-1000.
Hastwell AH, Gresshoff PM, Ferguson BJ (2015) The structure and activity of nodulation-suppressing CLE peptide hormones of legumes. Functional Plant Biology, Goldacre Paper, 42: 229–238.
Hayashi S, Gresshoff PM, Ferguson BJ (2014) Mechanistic action of gibberellins in legume nodulation. Journal of Integrative Plant Biology 56: 971-978.
Hayashi S, Reid DE, Lorenc M, Stiller J, Edwards D, Gresshoff PM, Ferguson BJ (2012) Transient Nod-factor dependent gene expression in the nodulation competent zone of soybean (Glycine max L. Merr.) roots. Plant Biotechnology Journal 10: 995-1010.
Reid DE, Ferguson BJ, Gresshoff PM (2011a) Inoculation- and nitrate-induced CLE peptides of soybean control NARK-dependent nodule formation. Molecular Plant-Microbe Interactions 24: 606-618.
Reid DE, Ferguson BJ, Hayashi S, Lin Y-H, Gresshoff PM (2011b) Molecular mechanisms controlling legume autoregulation of nodulation. Annals of Botany 108: 789-795.
Renton M, Hanan J, Ferguson BJ, Beveridge CA (2012) Models of long-distance transport: How is carrier-dependent auxin transport regulated in the stem? New Phytologist 194: 704-715.
Reid DE, Li D, Ferguson BJ, Gresshoff PM (2013) Structure-function analysis of the GmRIC1 signal peptide and CLE domain required for nodulation control in soybean. Journal of Experimental Botany 64: 1575-1585.
Young NF, Ferguson BJ, Antoniadi I, Bennett MH, Beveridge CA, Turnbull CGN (2014) Conditional auxin response and differential cytokinin profiles in shoot branching mutants. Plant Physiology 165: 1723–1736.
Wang Y, Wang L, Zou Y, Chen L, Cai Z, Zhang S, Zhao F, Tian Y, Jiang Q, Ferguson BJ, Gresshoff PM, Li X (2014) Soybean miR172c targets the repressive AP2 transcription factor GmNNC1 to activate GmENOD40 expression and regulate nodule initiation. The Plant Cell 26: 4782–4801.