... understanding life in molecular detail

Dr Yoselin Benitez Alfonso

Cell-to-cell communication, Plasmodesmata, Plant development, Cell wall biopolymers


Research in my lab focus on understanding the molecular and structural composition of plasmodesmata:channels that communicate plant cells to allow for the transport of proteins, miRNAs, small RNAs, viruses, metabolites and other signalling molecules. Knowledge extracted from plasmodesmata microdomains is used to modify intercellular signalling leading to changes in plant development and response to the environment. We also exploit the properties of cell wall structural components that modulate plasmodesmata transport in the design of hydrogels for a variety of applications.

Current major projects include:
  • Exploiting knowledge on plasmodesmata structure to design new biomaterials and hydrogels
  • Dissecting the role of plasmodesmata in the root response to nutrients and abiotic stress conditions
  • Manipulating signalling cues associated to legumes-rhizobia symbiosis and nitrogen fixation
  • Characterization of cell walls surrounding plasmodesmata and their function in communication

Plasmodesmata are membraneous channels embedded in plant cell walls. Via plasmodesmata, small and relatively large signalling molecules move and control developmental behaviours and environmental responses in neighbouring tissues. We focus on dissecting the regulation of these channels and its function in root signalling / responses. Cell walls microdomains surrounding plasmodesmata control channel aperture and transport capacity. Interactions between cellulose, callose and other glycans polymers are principal determinants in plasmodesmata mechanical properties. We use interdisciplinary approaches (cell and molecular biology, soft polymer physics and computer simulations) to model plasmodesmata structure and to identify the factors that control their composition, properties and transport capacity. The aim is to elucidate their biological function and design strategies to manipulate their regulation for the improvement of important agricultural traits. Information extracted from cell walls is also exploited in the design of new biomaterials, mainly in hydrogel form, that can be used as environmental friendly alternatives in a variety of applications.

 

Current research projects

Characterization of cell walls surrounding plasmodesmata and their function in communication

The accumulation of the polymer callose (β-1,3 glucans) in the cell wall constricts the channel aperture, modulating intercellular molecular flux. We are closely studying the proteins involved directly and indirectly in the metabolism of callose at plasmodesmata. We are also dissecting the contribution of other cell wall components in regulating channel structure/aperture. We are also modelling the properties of cell walls around plasmodesmata using composite mixtures and soft polymer physic approaches such as NMR, rheology and AFM nanoindentation. The aim is to link structural and physico-mechanical properties to understand the function of callose and other cell wall biopolymers in regulating the channel transport capacity. This information is essential to manipulate these channels aiming to optimize plant development and environmental responses.

 

Dissecting the role of plasmodesmata in the root response to nutrients and abiotic stress conditions

We are using symplastic reporters to study changes in plasmodesmata transport and structure in response to N, P, K and osmotic stress (simulating drought). The aim is to discover factors and components affecting intercellular signalling during the plant response to these stress conditions. Mutants and transgenic lines affecting plasmodesmata permeability will indicate the importance of this pathway in concerting stress responses and highlight new avenues for strategic modifications of root traits to improve plant resilience to climate change.

 

Manipulating signalling cues associated to legumes-rhizobia symbiosis and nitrogen fixation

Formation and patterning of lateral root primordia are miss-regulated in mutants in plasmodesmata located 1,3 beta glucanases, involved in callose regulation (Benitez-Alfonso et al., Developmental Cell, 2013). We are currently investigating how the expression of these proteins affect the formation of nodules in Medicago truncatula roots and nitrogen-fixing symbiosis. We have observed that when we open plasmodesmata, nodulation is improved (Gaudioso-Pedraza et al., Current Biology 2018). The aim is to understand the role of callose and plasmodesmata in regulating the formation of diverse lateral organs and the plant response to nitrogen depleted and sufficient conditions.

 

Exploiting knowledge on plasmodesmata structure to design new biomaterials and hydrogels

Cell wall polymers occur at plasmodesmata in combination with cellulose and play a function in regulating transport capacity. New polymer mixtures are studied for their properties and this knowledge is applied in the manufacture of new environmentally-friendly materials (through interaction with industry). We found how interactions callose/cellulose can modify the properties of polymer mixtures (Abou-Saleh et al., Nature Communications, 2018) and in collaboration with the company Futamura also demonstrated that xyloglucan/xylan content can also modify cellulose applications in the making of paper and packaging material.

Detailed research programme                  Close ▲
YBA.jpg

Lecturer in Plant sciences
PhD (University of Cordoba, Spain) 2003
FHEA

Academic Fellow (University of Leeds) 2013-2017
Postdoc (John Innes Centre, Norwich) 2009-2013
Postdoc (Cold Spring Harbor Labs, NY, USA) 2004-2009

Miall 9.18
School of Biology
0113 343 2811
y.benitez-alfonso@leeds.ac.uk

benitezalfonso.wordpress.com

Selected Publications

  1. Abou-Saleh, R. H., Hernandez-Gomez, M., Amsbury, S., Paniagua, C., Bourdon, M., Miyashima, S., . . .Benitez Alfonso, Y. (2018). Interactions between callose and cellulose revealed through the analysis of biopolymer mixtures. Nature Communications, 9. doi:10.1038/s41467-018-06820-y

  2. Gaudioso-Pedraza, R., Beck, M., Frances, L., Kirk, P., Ripodas, C., Niebel, A., Benitez-Alfonso, Y.# de Carvalho-Niebel, F# (2018). Callose-Regulated Symplastic Communication Coordinates Symbiotic Root Nodule Development. Current Biology, 28(22), 3562-3577.e6. doi:10.1016/j.cub.2018.09.031. # equal corresponding authors.

  3. Benitez-Alfonso, Y., Faulkner, C., Pendle, A., Miyashima, S., Helariutta, Y., & Maule, A. (2013). Symplastic Intercellular Connectivity Regulates Lateral Root Patterning. Developmental Cell, 26(2), 136-147. doi:10.1016/j.devcel.2013.06.010