A long and winding road: symposium on membrane trafficking in plants.

Abstract

The Society for Experimental Biology symposium on Membrane Trafficking in Plants took place in Glasgow between 23 and 26 August 2003 and was organized by M. Blatt and G. Thiel. ![][1] In August 2003, the plant endomembrane community gathered under the auspices of the Society for Experimental Biology to consider the latest developments in the rapidly growing field of the plant secretory pathway. The meeting was preceded by the two‐day annual gathering of the European Plant Secretory Pathway Group, during which postgraduates and postdocs presented their latest data. Plants have homologues of the majority of the vertebrate and yeast genes that encode both the structural and the regulatory proteins of the secretory pathway. However, it is clear that plant cells are different in (1) the organization and operation of the components of the pathway, such as highly motile Golgi stacks, (2) the necessity to sort proteins into different vacuoles and (3) the need to organize a precisely orientated apparatus for cell division (Fig 1). Here we consider the highlights of the meeting and the controversies surrounding the mechanisms by which the plant cell exports material from the site of synthesis to the site of action and imports material from the external environment. Figure 1. A simplified map of the secretory pathway of higher plants. Cargo synthesized and processed in the endoplasmic reticulum (ER) is transferred directly to the closely apposed and mobile Golgi apparatus (G). However, direct transfer of some storage proteins to the vacuole may occur (route 1). Proteins destined for the protein storage vacuole may leave the Golgi at the cis ‐ and trans ‐compartments (route 2), whilst exocytotic cargo predominantly leaves at the trans‐ face (route 3). Product destined for the lytic vacuole is sorted at the trans ‐Golgi and routed in a clathrin‐ and receptor‐dependent fashion through a prevacuolar … [1]: /embed/graphic-1.gif