Calcium transport in the cellular slime mould Dictyostelium discoideum

FEBS Letters

Europe-Finner, G.N.¹  Newell, P.C.¹ 

[1] Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, England

关键词: Calcium;    Dictyostelium;    Folate;    Cyclic AMP;    Chemotaxis;   

DOI  :  10.1016/0014-5793(85)81341-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Transport of Ca²⁺ into amoebae of Dictyostelium discoideum was studied using ⁴⁵Ca and a lanthanum stopping technique. Ca²⁺ uptake was found to be rapid and showed saturation kinetics. No difference was found in Ca²⁺ uptake between vegetative and aggregation competent cells, the V _max for unstimulated amoebae being approx. 10 nmol/10⁷ cells per min. Ca²⁺ uptake had the characteristics of passive facilitated diffusion using a saturatable carrier and NaN₃ and ouabain were not inhibitory. The chemoattractants cAMP and folate, previously reported to stimulate the uptake of Ca²⁺ into amoebae, did not stimulate the rate of Ca²⁺ uptake by this carrier but increased the extent of Ca²⁺ taken up over the period 10–30 s after chemotactic stimulation. The significance of these findings for the function of Ca²⁺in chemotactic signalling is discussed.

【 授权许可】

Unknown