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Structural Biology 2018
Volume: 4
Biochemistry & Molecular Biology Journal
Page 69
March 15-16 2018
Barcelona, Spain
10th Edition of International Conference on
Structural Biology
Intercellular communication is critical for multicellularity. Plants
have developed remarkable cellular machines such as the
plasmodesmata (PD) pores which interconnect every single
cell within the plant body, establishing direct membrane and
cytoplasmic continuity; a situation unique to plants. A striking
feature of PD organization setting them apart from animal
cell junctions is a strand of tightly constricted endoplasmic
reticulum (ER) called the desmotubule forming the center of
plasmodesmata and connected to the PM by tethering elements
which appear like spokes by electron microscopy and are
assumed to be proteinaceous. Very recently, it was shown by the
team of E. Bayer that highly plasmodesmata-enriched proteins,
members of the multiple C2 domains and transmembrane region
proteins (MCTPs) were significantly more abundant in PD with
tight membrane connections, and exhibit the domain architecture
expected of membrane tethering proteins, with multiple lipid-
binding C2 domains in the N-terminal, and an ER-anchored
transmembrane region in the C-terminal region. Our work is
focused on investigating the potential docking of C2 domains
of MCTPs on the plant plasma membrane at a molecular level.
We first performed sequence analysis to accurately define the
C2 domains from the MCTP and to obtain good 3D models by
homology modeling. Then, molecular dynamics is carried out to
predict the docking of the different C2 domains onto biomimetic
plant plasma membrane and eventually lipid specificity. Based
on these results and sequence analysis, specific binding sites
in the C2 domains could be predicted. Our preliminary results
suggest that the different C2 domains of MCTP proteins could
have different roles in lipid tethering, depending or not of calcium.
Sequence analysis and molecular dynamics to decipher the role
of C2 domains from plant plasmodesmata MCTP proteins for
membrane tethering
Lins Laurence1, Petit Jules1, Crowet Jean Marc1, Deleu, Magali1 and Bayer Emmanuelle2
1Université de Liège, Belgium
2Université de Bordeaux, France
Biochem Mol biol J, Volume 4
DOI: 10.21767/2471-8084-C1-009