Endocytosis and Cytoskeleton: Dynamic Encounters Shaping the Portals of Cell Entry
Genetic and pharmacological studies coupled with live imaging have portrayed the crosstalk between cytoskeleton and endocytic pathways of yeast, animals, and plants. Localized actin nucleation at endocytic foci seems to be the driving force for endocytic vesicle formation in yeasts and animals. Actin microfilaments also serve as tracks for intracellular transport of internalized endocytic vesicles. In addition, microtubules serve as the tracks for long range transport of endosomes in mammalian cells. Distinct actin and microtubule associated motor proteins facilitate this transport processes. Depolymerization of cortical actin in plants does not block entry of cargo in cells. However, subsequent trafficking processes are affected indicating a major role of actin in long range transport of endocytic vesicles. In plants involvement of microtubules in endocytic processes specializes both in non-dividing and dividing cells. In interphase cells, cortical microtubules co-align with pinching endocytic vesicles while endoplasmic microtubules direct the trajectories of endocytic materials during mitosis. Microtubules play key roles in delivering secreted and endocytic cargos to the newly assembling cell plate. Thus, with some conserved features of cytoskeletal involvement in endocytosis from yeast and animals, plants shape a unique dialogue between the cytoskeleton and membrane trafficking in order to meet plant-specific needs.
KeywordsPollen Tube Actin Filament Actin Cytoskeleton Cell Plate Endocytic Pathway
- Dhonukshe P, Grigoriev I, Fischer R, Tominaga M, Robinson DG, Hasek J, Paciorek T, Petrášek J, Seifertová D, Tejos R, Meisel LA, Zažímalová E, Gadella TW Jr, Stierhof YD, Ueda T, Oiwa K, Akhmanova A, Brock R, Spang A, Friml J (2008) Auxin transport inhibitors impair vesicle motility and actin cytoskeleton dynamics in diverse eukaryotes. Proc Natl Acad Sci U S A 105:4489–4494PubMedCrossRefGoogle Scholar
- Favery B, Chelysheva LA, Lebris M, Jammes F, Marmagne A, De Almeida-Engler J, Lecomte P, Vaury C, Arkowitz RA, Abad P (2004) Arabidopsis formin AtFH6 is a plasma membrane-associated protein upregulated in giant cells induced by parasitic nematodes. Plant Cell 16:2529–2540PubMedCrossRefGoogle Scholar
- Gekle M, Mildenberger S, Freudinger R, Schwerdt G, Silbernagl S (1997) Albumin endocytosis in OK cells: dependence on actin and microtubules and regulation by protein kinases. Am J Physiol 272:668–677Google Scholar
- Li R, Liu P, Wan Y, Chen T, Wang Q, Mettbach U, Baluška F, Šamaj J, Fang X, Lucas WJ, Lin J (2012) A membrane microdomain-associated protein, Arabidopsis Flot1, is involved in a clathrin-independent endocytic pathway and is required for seedling development. Plant Cell. doi: 10.1105/tpc.112.095695 Google Scholar