title: Involvement of cyanide-resistant respiration in cell-type proportioning during Dictyostelium development.
abstract: Involvement of cyanide (CN)-resistant respiration in cell-type proportioning was analyzed using the developmental system of Dictyostelium discoideum. When migrating slugs were vitally stained with rhodamine 123, which is known to stain actively respirating mitochondria coupled with an elevated electronic potential of the inner membrane, the posterior prespore region was stained more strongly than the anterior prestalk region. Application of benzohydroxamic acid (BHAM) and propyl gallate, specific inhibitors of CN-resistant respiration, to starved Dictyostelium cells induced formation of unique cell masses, in which almost all of the cells differentiated into stalk-like cells with a large vacuole and thick cell wall. BHAM was also found to enhance the expressions of prestalk-specific genes such as ecmA and ecmB in the unique cell mass in a position-dependent manner. In contrast, the expression of a prespore-specific gene, Dp87, was almost completely inhibited by BHAM. Taken together these results strongly suggest the involvement of CN-resistant respiration in the proportion regulation of cell types differentiating during the Dictyostelium development.
authors.affiliation: Biological Institute, Faculty of Science, Tohoku University, Sendai, Japan.
authors.forename: S I
authors.initials: SI
authors.lastname: Matsuyama
authors.forename: Y
authors.initials: Y
authors.lastname: Maeda
mesh_terms: D000818:Animals; D001386:Azides / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D002465:Cell Movement; D004396:Coloring Agents; D003486:Cyanides / Q000494:pharmacology*; D004023:Dictyostelium / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis; D005656:Fungal Proteins / Q000096:biosynthesis; D015870:Gene Expression / Q000187:drug effects; D005800:Genes, Fungal / Q000187:drug effects; D006877:Hydroxamic Acids / Q000494:pharmacology; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D009024:Morphogenesis / Q000187:drug effects; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology*; D015800:Protozoan Proteins; D020112:Rhodamine 123; D012235:Rhodamines; D019810:Sodium Azide; D013172:Spores, Fungal
chemical_list: D001386:Azides; D004396:Coloring Agents; D003486:Cyanides; D016326:Extracellular Matrix Proteins; D005656:Fungal Proteins; D006877:Hydroxamic Acids; D015800:Protozoan Proteins; D012235:Rhodamines; C069214:ecmB protein, Dictyostelium; D020112:Rhodamine 123; D019810:Sodium Azide; C006696:benzohydroxamic acid