Adjustment of osmotic pressure coupled with change of growth mode in Spirogyra
Katsuhisa Yoshida A C D , Ai Ohtani A , Tetsuro Mimura B and Teruo Shimmen AA Department of Life Science, Graduate School of Life Science, University of Hyogo, Kouto 3-2-1, Harima Science Park City, Hyogo 678-1297, Japan.
B Graduate School of Science, Kobe University, Rokkodai 1-1, Nada, Kobe 678-8501, Japan.
C Present address: Graduate School of Science, Kobe University, Rokkodai 1-1, Nada, Kobe 678-8501, Japan.
D Corresponding author. Email: yoshikatsu@silver.kobe-u.ac.jp
Functional Plant Biology 35(7) 580-584 https://doi.org/10.1071/FP08138
Submitted: 30 April 2008 Accepted: 1 July 2008 Published: 21 August 2008
Abstract
Spirogyra living in running water forms a rhizoid which anchors it to the substratum. Rhizoid differentiation can be induced in the laboratory by severing algal filaments. The terminal cell changes the growth mode from diffuse growth to tip growth, and finally differentiates to be a rhizoid. We found that the intracellular osmolarity of the rhizoid was significantly lower than that of other interjacent cells which did not form rhizoids. The decrease in the intracellular osmolarity began before the start of tip growth. TEA, a K+ channel blocker, inhibited the decrease in the intracellular osmolarity of the terminal cells; increase in the external K+ also inhibited this. It was suggested that K+ efflux through K+ channel is involved in the adjustment of osmotic pressure. When the adjustment of osmotic pressure was inhibited, tip growth did not start, inevitably, no rhizoid was formed. In Spirogyra sp. which was unable to form rhizoids, the terminal cell did not show the adjustment of osmotic pressure. Thus, this adjustment seems to be intimately coupled with the rhizoid differentiation. Possible roles of the adjustment of osmotic pressure in rhizoid differentiation are discussed.
Additional keywords: K+, rhizoid differentiation, tip growth, turgor pressure.
Bartnicki-Garcia S, Lippman E
(1972) The bursting tendency of hyphal tips of fungi: presumptive evidence for a delicate balance between wall synthesis and wall lysis in apical growth. Journal of General Microbiology 73, 487–500.
Benkert R,
Obermeyer G, Bentrup FW
(1997) The turgor pressure of growing lily pollen tubes. Protoplasma 198, 1–8.
| Crossref | GoogleScholarGoogle Scholar |
Bisson MA, Bartholomew D
(1984) Osmoregulation or turgor regulation in Chara? Plant Physiology 74, 252–255.
| PubMed |
Bisson MA, Kirst GO
(1980) Lamprothmnium, a euryhaline Chaarophyte. 1. Osmotic relations and membrane potential at steady state. Journal of Experimental Botany 31, 1223–1235.
| Crossref | GoogleScholarGoogle Scholar |
Green PB,
Erickson RO, Buggy J
(1971) Metabolic and physical control of cell elongation rate. Plant Physiology 47, 423–430.
| PubMed |
Guimil S, Dunand C
(2006) Patterning of Arabidopsis epidermal cells: epigenetic factors regulate the complex epidermal cell fate pathway. Trends in Plant Science 11, 601–609.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Inoue N,
Yamada S, Shimmen T
(2002) Rhizoid differentiation in Spirogyra: position sensing by terminal cells. Plant & Cell Physiology 43, 479–483.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Iwata K,
Tazawa M, Itoh T
(2001) Turgor pressure regulation and orientation of cortical microtubules in Spirogyra cells. Plant & Cell Physiology 42, 594–598.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Kamiya N, Kuroda K
(1956) Artificial modification of the osmotic pressure of the plant cell. Protoplasma 46, 423–436.
| Crossref | GoogleScholarGoogle Scholar |
Money NP, Harold FM
(1993) Two water molds can grow without measurable turgor pressure. Planta 190, 426–430.
| Crossref | GoogleScholarGoogle Scholar |
Nagata Y
(1973a) Rhizoid differentiation in Spirogyra. I. Basic features of rhizoid formation. Plant & Cell Physiology 14, 531–541.
Nagata Y
(1973b) Rhizoid differentiation in Spirogyra. II. Photoreversibility of rhizoid induction by red and far-red light. Plant & Cell Physiology 14, 543–554.
Nagata Y
(1977) Light-induced adhesion of Spirogyra cells to glass. Plant Physiology 59, 680–683.
| PubMed |
Nagata Y
(1979) Rhizoid differentiation in Spirogyra. III. Intracellular localization of phytochrome. Plant Physiology 64, 9–12.
| PubMed |
Okazaki Y, Tazawa M
(1986a) Involvement of calcium ion in turgor regulation upon hypotonic treatment in Lamprothamnium succinctum. Plant, Cell & Environment 9, 185–190.
Okazaki Y, Tazawa M
(1986b) Ca2+ antagonist nifecipine inhibits turgor regulation upon hypotonic treatment in internodal cells of Lamrothmnium. Protoplasma 134, 65–66.
| Crossref | GoogleScholarGoogle Scholar |
Okazaki Y,
Shimmen T, Tazawa M
(1984) Turgor regulation in a brackish charophyte, Lamprothamnium succinctum. I. Artificial modification of intracellular osmotic pressure. Plant & Cell Physiology 25, 565–571.
Okazaki Y,
Yoshimoto Y,
Hiramoto Y, Tazawa M
(1987) Turgor regulation and cytoplasmic free Ca2+ in the alga Lamprothamnium. Protoplasma 140, 67–71.
| Crossref | GoogleScholarGoogle Scholar |
Pierson ES,
Miller DD,
Callaham DA,
Shipley AM,
Rivers BA,
Cresti M, Hepler PK
(1994) Pollen tube growth is coupled to the extracellular calcium ion flux and the intracellular caldium gradient: effect of BAPTA-type buffers and hypertonic media. The Plant Cell 6, 1815–1828.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Smith DL
(1972) Staining and osmotic properties of young gametophytes of Polypodium vulgare L. and their bearing on rhizoid function. Protoplasma 74, 465–479.
| Crossref | GoogleScholarGoogle Scholar |
Takahashi K,
Isobe M,
Knight MR,
Trewavas AJ, Muto S
(1997a) Hypoosmotic shock induces increases in cytosolic Ca2+ in tobacco suspension-culture cells. Plant Physiology 113, 587–594.
| PubMed |
Takahashi K,
Isobe M, Muto S
(1997b) An increase in cytosolic calsium ion concentration precedes hypoosmotic shock-induced activation of protein kinase in tobacco suspension cells. FEBS Letters 401, 202–206.
| Crossref | GoogleScholarGoogle Scholar | PubMed |