Inhibition of na/h antiport activity in sugar beet tonoplast by analogs of amiloride.
نویسندگان
چکیده
The effects of amiloride and a series of amiloride analogs have been tested on the Na(+)/H(+) antiport activity in intact vacuoles and tonoplast vesicles isolated from sugar beet cell suspension cultures. There is a competitive interaction between amiloride analogs and sodium. Substitution of one or both H-atoms of the 5-amino group of amiloride (apparent K(i) about 150 micromolar) resulted in a 3- to 200-fold increase in inhibitory potency of the antiport activity.
منابع مشابه
Salt tolerance in suspension cultures of sugar beet : induction of na/h antiport activity at the tonoplast by growth in salt.
Cell suspension cultures of sugar beet were grown at various salinities (0-200 millimolar NaCl). Their tolerance to Na(+) was comparable to that of the intact plant. Tonoplast vesicles were prepared by sucrose density gradient centrifugation of microsomal membranes and shown to be highly purified. The vesicles were subjected to a pH jump in the presence of acridine orange and the rate of recove...
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ورودعنوان ژورنال:
- Plant physiology
دوره 85 1 شماره
صفحات -
تاریخ انتشار 1987