Y. Naidoo et G. Naidoo, Cytochemical localisation of adenosine triphosphatase activity in salt glands of Sporobolus virginicus (L.) Kunth, S AFR J BOT, 65(5-6), 1999, pp. 370-373
The ultracytochemical localisation of adenosine triphosphatase activity in
the bicellular salt glands of the halophytic grass, Sporobolus virginicus (
L.) Kunth, was investigated using a modified lead precipitation technique.
Electron dense lead deposits in the cells, following the lead phosphate pre
cipitation, suggested the localisation of membrane proton pumps and/or memb
rane associated soluble phosphatase. Staining was prominent in the plasma m
embrane of the basal cell, especially in the suberised neck-like protrusion
, and in the plasmodesmata. Staining was less prominent along the plasma me
mbrane invaginations, at the common wall between basal and cap cells. and a
long the partitioning membranes lining the channels within the basal cell.
The plasma membrane of the cap cell exhibited weak staining. Control tissue
, incubated in the absence of ATP, exhibited no staining. Evidence suggests
that ion loading into the basal cell and unloading from the cap cell are a
ctive processes.