Involvement of actin filaments in rhizoid morphogenesis of Spirogyra.
The role of actin filaments in rhizoid morphogenesis was studied in Spirogyra. When the algal filaments were severed, new terminal cells started tip growth and finally formed rhizoids. Actin inhibitors, latrunculin B and cytochalasin D, reversibly inhibited the process. A mesh-like structure of actin filaments (AFs) was formed at the tip region. Gd(3+) inhibited tip growth and decreased AFs in the tip region. Either a decrease in turgor pressure or lowering of the external Ca(2+) concentration also induced similar results. It was suggested that the mesh-like AF structure is indispensable for the elongation of rhizoids. A possible organization mechanism of the mesh-like AF structure was discussed.
Yoshida
Katsuhisa
K
Department of Life Science, Graduate School of Life Science, University of Hyogo, Harima Science Park City, Hyogo, Japan. yoshikatsu@silver.kobe-u.ac.jp
Shimmen
Teruo
T
D008841:Actin Cytoskeleton / Q000187:drug effects / Q000502:physiology*; D000199:Actins / Q000037:antagonists & inhibitors; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D000460:Chlorophyta / Q000187:drug effects / Q000254:growth & development* / Q000648:ultrastructure; D015638:Cytochalasin D / Q000494:pharmacology; D003595:Cytoplasmic Streaming / Q000187:drug effects; D005682:Gadolinium / Q000494:pharmacology; D009024:Morphogenesis; D053778:Thiazolidines / Q000494:pharmacology
D000199:Actins; D019086:Bridged Bicyclo Compounds, Heterocyclic; D053778:Thiazolidines; D015638:Cytochalasin D; D005682:Gadolinium; C037068:latrunculin B; D002118:Calcium