Members of the Arabidopsis Dynamin-Like Gene Family, ADL1, Are Essential for Plant Cytokinesis and Polarized Cell Growth[W]

Abstract

Polarized membrane trafficking during plant cytokinesis and cell expansion are critical for plant morphogenesis, yet very little is known about the molecular mechanisms that guide this process. Dynamin and dynamin-related proteins are large GTP binding proteins that are involved in membrane trafficking. Here, we show that two functionally redundant members of the Arabidopsis dynamin-related protein family, ADL1A and ADL1E, are essential for polar cell expansion and cell plate biogenesis. adl1A-2 adl1E-1 double mutants show defects in cell plate assembly, cell wall formation, and plasma membrane recycling. Using a functional green fluorescent protein fusion protein, we show that the distribution of ADL1A is dynamic and that the protein is localized asymmetrically to the plasma membrane of newly formed and mature root cells. We propose that ADL1-mediated membrane recycling is essential for plasma membrane formation and maintenance in plants.

CHOLINE TRANSPORTER-LIKE1 is required for sieve plate development to mediate long-distance cell-to-cell communication

“…Furthermore, we analysed the behaviour of two dynamin-related proteins, DRP1A and DRP1C, which are involved in the clathrinmediated endocytosis in plants [42][43][44] . As previously reported, both DRP1A and DRP1C localize to the cell plate and the plasma membrane of expanding and fully expanded interphase cells 44,45 . Notably, we found that both DRP1A and DRP1C exhibit a similar polarized pattern to that of CHER1 in SE cells (Fig.…”

Vesicle Trafficking during Somatic Cytokinesis

“…Stubs at either side of the cell can be caused by defective maturation and tearing of the plate in mutants impeded in cell wall formation (Nickle and Meinke, 1998;Fagard et al, 2000;Schrick et al, 2000Schrick et al, , 2004Zuo et al, 2000;Lane et al, 2001;Lukowitz et al, 2001;Pagant et al, 2002). However, this does not explain the presence of stubs in mutants affected in early cell plate vesicle-trafficking events, like KN and KEULE (Lauber et al, 1997;Waizenegger et al, 2000), stomatal cytokinesis defective1 (Falbel et al, 2003), the dynamin drp1A drp1E double mutant (Kang et al, 2003a), the double gn/gnl1 mutant mimicked by BFA treatment of gnl1 (Reichardt et al, 2007), and dominant inhibitory mutants of RAB-A2 (Chow et al, 2008). As the inhibition of both GN and GNL1 impairs ER-to-Golgi vesicle trafficking and traps KN in the ER, the cell wall stubs have to be generated by a KN-independent pathway (Lauber et al, 1997;Jurgens, 2005a).…”

“…Interestingly, in BY-2 cells, clathrin as well as several DRP1 family proteins accumulate at the periphery of the cell plate, where vesicle fusion takes place (Hong et al, 2003;Kang et al, 2003aKang et al, , 2003bTahara et al, 2007), which could reflect membrane recycling.…”

FtsZ and the division of prokaryotic cells and organelles

“…One possible reason for its visibility is that this machine consists of at least three layers: an innermost ring comprising FtsZ, followed by the plastid dividing ring that is visible by negative staining but is of unknown composition 102 , and an outermost ring on the outside of the organelle that contains a dynamin-like protein (DRP) 103,104 . Dynamins are eukaryotic GTPases that assemble on membranes and mediate membrane fission 97 ; dynamin also has a role in cytokinesis of animal and plant cells 105,106 . DRPs have no structural homology with FtsZ, and obvious homologues are absent from prokaryotes.…”