Induction of a New Alkaline Band at a Target Position in Internodal Cells of Chara corallina

Abstract

;Characean cells develop alternating alkaline and acid bands on their surface upon illumination. However, the mechanism of band formation is not fully understood. In the present study, we succeeded in inducing a new alkaline band at an original acid band in internodal cells of Chara corallina. Chloroplasts in an acid band were locally removed by wounding the cell in the absence of the cell turgor pressure. The chloroplast-removed area was observed as a white belt in a green cylindrical internodal cell. This internodal cell developed a new alkaline band on the surface at the chloroplast-removed area. The narrower the chloroplast-removed area, the less significant the extent of OH -extrusion. This is the first success in inducing a new alkaline band at a target position in Characeae.

Involvement of Membrane Potential in Alkaline Band Formation by Internodal Cells of Chara corallina

“…Alkaline bands were visualized using a pH indicator dye, phenol red (Spear et al 1969, Takano and Shimmen 1999, Shimmen and Yamamoto 2002. The pK a value of phenol red is 8.0, and the color exhibits a gradual transition from yellow to red over the pH range 6.6-8.0.…”

Cell wall and cell growth characteristics of giant‐celled algae

“…Internodal cells of characean algae, i.e., species of the genera Chara (Figs 3, 4) and Nitella , have been used for cell wall and cell growth studies for several decades. ‘Alkaline bands’ are formed along cell peripheries, around which the pH of the surrounding extracellular fluid is elevated (Shimmen & Yamamoto ). Because cell growth along the long axis is predominant (Richmond ), lateral cell walls elongate anisotropically in the longitudinal direction in cells of growing tissues in higher plants.…”

Spatial coordination of chloroplast and plasma membrane activities in chara cells and its disruption through inactivation of 14-3-3 proteins

“…The effective quantum yield of PSII activity was low in the high pH regions (alkaline zones) and was high in the acidic zones. A recent finding that alkaline zones are induced in Chara cells when the chloroplasts are moved away from the targeted area [31] provide indirect evidence in support of the low photosynthetic activity of chloroplasts in the alkaline cell regions. An important question is whether there is a causal coupling between the pH banding pat tern and the PSII photochemical yield, or whether they can be changed independently.…”