Research in Dr Gibbs' lab utilises molecular, genetic and biochemical approaches to investigate how plants use targeted protein degradation as a mechanism for sensing and responding to diverse developmental and environmental signals. The general aim of our work is to increase our understanding of how plants develop and respond to the environment, and to identify promising targets that can be manipulated in agriculturally important crops to improve growth, productivity and stress tolerance.
Proteins are major functional components of cells, and the regulation of their turnover is essential for controlling cellular responses and developmental outputs. In plants, targeted proteolysis has important roles in sensing and coordinating responses to internal developmental cues (e.g. phytohormones, such as auxin) and environmental signals (e.g. oxygen availability). The "N-end rule pathway" is an ancient and highly evolutionarily conserved proteolytic system that targets proteins for destruction based on the nature of their N-terminus (the beginning of the protein). We recently identified the first targets of this pathway in the plant kingdom, and showed that they mediate plant perception and response to low oxygen stress (hypoxia), a situation that frequently occurs during floods (Gibbs et al. 2011 Nature). This is the first example of a direct molecular mechanism for oxygen sensing in plants, and represents a major breakthrough for the future development of flood-tolerant crops, a key focus for food security. More recently, this same pathway has been shown to mediate perception and transduction of nitric oxide (NO), an important developmental signaling molecule in plants (Gibbs et al., 2014 Molecular Cell). This highlights the importance of N-end rule-mediated protein degradation in plants, and our ongoing studies suggest that the N-end rule plays a key role in a wide range of other developmental and physiological processes.
Current research is focused on characterizing novel ‘branches’ and protein substrates of the N-end rule pathway in Arabidopsis, with a particular focus on linking the control of protein stability to agriculturally important developmental processes and abiotic stress responses. Furthermore, our studies aim to provide insight into the evolution of signal transduction mechanisms in multicellular organisms.
Please see Dr. Gibbs’ lab websiteand Google Scholar profile
Marín-de la Rosa N, Sotillo B, Miskolczi P, Gibbs DJ, Vicente-Condo J, Carbonero P, Oñate-Sánchez L, Holdsworth MJ, Bhalerao R, Alabadí D, Blázquez MA (2014) Large-scale identification of gibberellin-related transcription factors defines Group VII ERFs as functional DELLA partners. Plant Physiology. DOI:10.1104/pp.114.244723
Gibbs DJ and Coates JC (2014) AtMYB93 is an endodermis-specific transcriptional regulator of lateral root development in Arabidopsis. Plant Signalling and Behaviour. DOI:10.4161/psb.29808
Gibbs DJ*, Bacardit J, Bachmair A, Holdsworth MJ* (2014) The eukaryotic N-end rule pathway: conserved mechanisms and diverse functions. Trends in Cell Biology. http://dx.doi.org/10.1016/j.tcb.2014.05.001. *co-corresponding author
Gibbs DJ, Isa NM, Movahedi M, Lozano-Juste J, Mendiondo GM, Berckhan S, Marín-de la Rosa N, Vicente Conde J, Sousa Correia C, Pearce, SP, Bassel GW, Hamali B, Talloji P, Tomé DFA, Coego A, Beynon J, Alabadí D, Bachmair A, León J, Gray JE, Theodoulou FL, Holdsworth MJ (2014) Nitric oxide sensing in plants is mediated by proteolytic control of Group VII ERF transcription factors. Molecular Cell, 10.1016/j.molcel.2013.12.020
Gibbs DJ, Voss U, Harding SA, Fannon J, Moody LA, Yamada E, Swarup K, Nibau C, Bassel GW, Choudhary A, Lavenus J, Bradshaw SJ, Stekel DJ, Bennett MJ, Coates JC (2014) AtMYB93 is a novel negative regulator of lateral root development in Arabidopsis. New Phytologist. DOI: 10.1111/nph.12879.
Bassel GW, Stamm P, Mosca G, Barbier de Reuille P, Gibbs DJ, Winter RM, Janka A, Holdsworth MJ, Smith RS (2014)Mechanical constraints imposed by 3D cellular geometry and arrangement modulate growth patterns in the Arabidopsis embryo. Proc Natl Acad Sci USA. doi: 10.1073/pnas.1404616111
Bailey-Serres J, Fukao T, Gibbs DJ, Holdsworth MJ, Lee SC, Licausi F, Perata P, Voesenek LA, van Dongen JT (2012) Making sense of low oxygen sensing. Trends Plant Sci.17(3):129-38
Gibbs DJ, Lee SC, Isa NM, Gramuglia S, Fukao T, Bassel GW, Correia CS, Corbineau F, Theodoulou FL, Bailey-Serres J, Holdsworth MJ (2011) Homeostatic response to hypoxia is regulated by the N-end rule pathway in plants. Nature. 479(7373):415-8.
Bassel GW, Lan H, Glaab E, Gibbs DJ, Gerjets T, Krasnogor N, Bonner AJ, Holdsworth MJ, Provart NJ (2011) Genome-wide network model capturing seed germination reveals coordinated regulation of plant cellular phase transitions. Proc Natl Acad Sci U S A. 108(23):9709-14
Nibau C, Gibbs DJ, Bunting KA, Moody LA, Smiles EJ, Tubby JA, Bradshaw SJ, Coates JC (2011) ARABIDILLO proteins have a novel and conserved domain structure important for the regulation of their stability. Plant Mol Biol. 75(1-2):77-92.
Nibau C*, Gibbs DJ*, Coates JC (2008) Branching out in new directions: the control of root architecture by lateral root formation. New Phytol. 179(3):595-614. *Joint first author.