Constriction of endoplasmic reticulum tubules by the viral movement protein BMB2 is associated with local BMB2 anchorage at constriction sites.

Fiche publication


Date publication

décembre 2020

Journal

Plant signaling & behavior

Auteurs

Membres identifiés du Cancéropôle Est :
Dr HEINLEIN Manfred


Tous les auteurs :
Lazareva EA, Lezzhov AA, Dolja VV, Morozov SY, Heinlein M, Solovyev AG

Résumé

Plant virus-encoded movement proteins (MPs) interact with endoplasmic reticulum (ER) membranes, the cytoskeleton, and plasmodesmata (PD) to mediate intracellular delivery of the virus genome to PD and its further transport through PD from infected to healthy cells. The MP termed BMB2 has been shown to induce constrictions of ER tubules and to occur at highly curved membranes, thus showing properties similar to those of reticulons, a class of cellular proteins inducing membrane curvature and shaping the ER tubules. Consistent with this BMB2 function, mRFP-BMB2 localizes to discrete, constricted regions scattered along the ER tubules. Here, using BMB2-mRFP fusion protein as a BMB2 derivative with partially disabled functionality, we demonstrate that the focal localization of BMB2 to discrete sites along the ER tubules is insufficient to induce local tubule constrictions at these sites, suggesting that the formation of ER tubule constrictions represents a specific BMB2 function and is not simply a mechanistic consequence of its localization to the ER. The presented data suggest that the formation of ER-residing BMB2-containing distinct small aggregates, or protein platforms, can be uncoupled from BMB2-induced ER tubule constrictions, whereas the anchoring of platforms at particular ER sites appears to be linked to the constriction of ER tubules at these sites.

Mots clés

Plasmodesmata, cell-to-cell transport, endoplasmic reticulum, membrane curvature, movement protein, plant virus, reticulon

Référence

Plant Signal Behav. 2020 Dec 1;:1856547