TY - JOUR AU1 - Lehtonen, Juhani AU2 - Volanto-Lumppio, Katja AB - Abstract Significance of Ca2+ and K+ for the complex morphogenesis of Micrasterias, which takes place through multipolar tip growth, was investigated. Studies with different external Ca2+ concentrations and Ca2+ channel inhibitors LaCl3 and verapamil indicate that Ca2+ and Ca2+ channels are essential in the development, while treatments with different K+ concentrations and K+ channel inhibitor TEA demonstrate that potassium or K+ channels are not needed in the process, albeit the existence of K+ channels. K+ is not needed even for the regulation of turgor pressure, which was found to decrease clearly during cell development. The plasma membrane ATPase inhibitors diethylstilbesterol (DES) and Na-orthovanadate stop morphogenesis and indicate the importance of ion pumps in the developmental process. Both supraoptimal, external K+ and Ca2+ cause abundant Ca2+ precipitate formation in chloroplasts, which shows that chloroplasts are important in regulation of cytoplasmic Ca2+ metabolism and that K+ activates the uptake of Ca2+ through Ca2+ channels. Copyright © 1996. The Japanese Society of Plant Physiologists TI - Significance of Ca2+ and K+ in Micrasterias Growth and Morphogenesis JF - Plant and Cell Physiology DO - 10.1093/oxfordjournals.pcp.a029063 DA - 1996-12-01 UR - https://www.deepdyve.com/lp/oxford-university-press/significance-of-ca2-and-k-in-micrasterias-growth-and-morphogenesis-qxiY6IXqMn SP - 1126 EP - 1133 VL - 37 IS - 8 DP - DeepDyve ER -