title: Auxin deprivation induces synchronous Golgi differentiation in suspension-cultured tobacco BY-2 cells.
abstract: To date, the lack of a method for inducing plant cells and their Golgi stacks to differentiate in a synchronous manner has made it difficult to characterize the nature and extent of Golgi retailoring in biochemical terms. Here we report that auxin deprivation can be used to induce a uniform population of suspension-cultured tobacco (Nicotiana tabacum cv BY-2) cells to differentiate synchronously during a 4-d period. Upon removal of auxin, the cells stop dividing, undergo elongation, and differentiate in a manner that mimics the formation of slime-secreting epidermal and peripheral root-cap cells. The morphological changes to the Golgi apparatus include a proportional increase in the number of trans-Golgi cisternae, a switch to larger-sized secretory vesicles that bud from the trans-Golgi cisternae, and an increase in osmium staining of the secretory products. Biochemical alterations include an increase in large, fucosylated, mucin-type glycoproteins, changes in the types of secreted arabinogalactan proteins, and an increase in the amounts and types of molecules containing the peripheral root-cap-cell-specific epitope JIM 13. Taken together, these findings support the hypothesis that auxin deprivation can be used to induce tobacco BY-2 cells to differentiate synchronously into mucilage-secreting cells.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309-0347, USA. zwinicur@biosci.cbs.umn.edu
authors.forename: Z M
authors.initials: ZM
authors.lastname: Winicur
authors.forename: G F
authors.initials: GF
authors.lastname: Zhang
authors.forename: L A
authors.initials: LA
authors.lastname: Staehelin
mesh_terms: D002460:Cell Line; D005685:Galactans / Q000096:biosynthesis; D006056:Golgi Apparatus / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D007210:Indoleacetic Acids / Q000494:pharmacology*; D007700:Kinetics; D009077:Mucins / Q000096:biosynthesis; D010940:Plant Proteins / Q000096:biosynthesis; D018517:Plant Roots; D010947:Plants, Toxic; D013997:Time Factors; D014026:Nicotiana / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure
chemical_list: D005685:Galactans; D007210:Indoleacetic Acids; D009077:Mucins; D010940:Plant Proteins; C005653:arabinogalactan