Cell biology of the plant Golgi apparatus

Abstract

The higher plant Golgi apparatus, comprising many individual stacks of membrane bounded cisternae, is one of the most enigmatic of the cytoplasmic organelles. Not only can the stacks receive material from the endoplasmic reticulum, process it and target it to the correct cellular destination, but they can also synthesise and export complex carbohydrates and lipids and most likely act as one end point of the endocytic pathway. In many cells such processing and sorting can take place while the stacks are moving within the cytoplasm and, remarkably, the organelle manages to retain its structural integrity. This review considers some of the latest data and views on transport both to and from the Golgi and the mechanisms by which such activity is regulated.

Glycerolipid transfer for the building of membranes in plant cells

“…In plants, the Golgi apparatus is close to the ER but, although proteins exhibiting substantial homology with partners of the COPII complex are known, it was never possible to visualize any COPII-type vesicles. The ER to Golgi transfer does not seem to imply a vesicular stage [48]. It probably works with the COPII machinery but a COPII independent pathway is also possible [49].…”

“…Several studies have shown the existence of a Golgi to ER pathway in plants presumably working through COPI vesicles [48]. There is no doubt that the COPI machinery exists in plants and it is likely that COPI and COPII pathways are interdependent due to the necessity for recycling the regulatory machinery of the secretory pathway.…”

Tissue-Autonomous Promotion of Palisade Cell Development by Phototropin 2 inArabidopsis

“…Furthermore, ADP ribosylation factor, which is involved in vesicle trafficking (Takeuchi et al, 2002), has been shown to interact with PHOT1 in vitro (Sullivan et al, 2009). It has been reported that a part of PHOT2 is translocated in response to blue light from plasma membrane to the Golgi apparatus (Kong et al, 2006), which plays a crucial role in vesicle trafficking (Hawes, 2005). Hence, PHOT2 might promote the palisade cell development by altering the auxin distribution through its interaction with ADP ribosylation factor proteins.…”

Nanoscale Architecture of Endoplasmic Reticulum Export Sites and of Golgi Membranes as Determined by Electron Tomography

“…These investigations have produced three types of advances: (1) they have identified and characterized a multitude of structural and regulatory proteins that operate at different sites in the secretory pathway; (2) they have produced insights into targeting and retention signals; and (3) they have provided information on the dynamic properties of the compartments with which these proteins are associated. A number of excellent reviews summarizing progress in these fields of research have been published in recent years (SaintJore-Dupas et al, 2004;Hawes, 2005;Hawes and Satiat-Jeunemaitre, 2005;Aniento et al, 2006;Hanton et al, 2006;Lam et al, 2007;Moreau et al, 2007;Robinson et al, 2007). The purpose of this review is 2-fold: first, to provide an update of studies of the structural organization of the secretory membrane systems of plants and, second, to explain the implications of this new information in terms of functional organization of these membrane compartments.…”