Injection of a Ca^<2+>-Chelating Agent into the Cytoplasm Retards the Progress of Turgor Regulation upon Hypotonic Treatment in the Alga, Lamprothamnium
スポンサーリンク
概要
- 論文の詳細を見る
The turgor regulation induced by hypotonic treatment (hypotonic turgor regulation) in the brackish-water alga Lamprothamnium succinctum is accompanied by a transient increase in the electrical conductance of the membrane, membrane depolarization and a transient increase in the cyioplasmic concentration of free Ca^<2+> ([Ca^<2+>]_c) (Okazaki and Tazawa 1990). In the present study, we loaded a Ca^<2+>-chelating agent, ECTA, into the cyioplasm by mechanical injection in order to suppress the increase in [Ca^<2+>]_c, that occurs during the hypotonic turgor regulation. The rate of the cyioplasmic streaming was taken as an indirect indicator of [Ca^<2+>]_c, since cyioplasmic streaming has been shown to be inhibited by high [Ca^<2+>]_c, in Lamprothamnium cells. The lag time for the inhibition of the cytoplasmic streaming upon hypotonic treatment was significantly prolonged in EGTA-loaded cells as compared to that in intact cells. This result indicates that the loaded cyioplasmic EGTA functioned as a buffer of Ca^<2+> to retard the increase in [Ca^<2+>]_c. It took a longer time for the membrane conductance to reach the peak value in EGTA-loaded cells than in intact cells. Membrane depolarization was affected to an insignificant extent by the cyioplasmic EGTA. The regulation of turgor pressure itself was partially inhibited. These results strongly support the idea that the net efflux of ions that occurs during the recovery from hypotonically induced changes in turgor pressure is controlled by [Ca^<2+>]_c.
- 日本植物生理学会の論文
著者
-
Iwasaki Naohiko
Dept. Biol. Osaka Med. College
-
Iwasaki Naohiko
Osaka Medical College Department Of Biology
-
Iwasaki Naohiko
Dept. Biol. Osaka Med. Coll.
-
Okazaki Yoshiji
Osaka Medical College Department Of Biology
関連論文
- CONTINUOUS MEASUREMENT OF TURGOR PRESSURE WITH TURGOR BALANCE METHOD AIDED BY COMPUTER IMAGE ANALYSIS
- Involvement of a Calcium-Dependent Protein Kinase in Hypoosmotic Turgor Regulation in a Brackish Water Characeae Lamprothamnium succinctum
- CHARACTERISTICS OF WATER CHANNELS IN CHARAINHIBITION BY MERCURY AND ZINC
- Anti-DUNALIELLA CDPK ANTIBODY INHIBITSHYPOTONIC TURGOR REGULATION IN BRACKISH WATER CHARACEAELAMPROTHAMNIUM
- CHARACTERISTICS OF WATER CHANNELS INCHARA II
- Light-Induced Changes in Cytosolic pH in Leaf Cells of Egeria densa : Measurements with pH-Sensitive Microelectrodes : ENVIRONMENTAL AND STRESS RESPONSES : MEMBRANES AND BIOENERGETICS
- Injection of a Ca^-Chelating Agent into the Cytoplasm Retards the Progress of Turgor Regulation upon Hypotonic Treatment in the Alga, Lamprothamnium
- HYPOTONIC TURGOR REGULATION AND VACUOLAR CALCOUM IN Lamprothamnium CELLS
- Tugor Regulation in a Brackish Water Charophyte, Lamprothamnium succinctum