Electrophysiology of the marine diatom Coscinodiscus wailesii -: I.: Endogenous changes of membrane voltage and resistance

被引:17
作者
Boyd, CM [1 ]
Gradmann, D
机构
[1] Dalhousie Univ, Dept Oceanog, Halifax, NS B3H 4J1, Canada
[2] Univ Gottingen, Albrecht von Haller Inst Pflanzenwissensch, Abt Biophys Pflanze, D-37073 Gottingen, Germany
关键词
diatoms; marine algae; membrane resistance; membrane voltage;
D O I
10.1093/jexbot/50.333.445
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
Double-barrelled micropipettes have been used to record the endogenous electrical behaviour of the marine diatom Coscinodiscus wailesii, diameter about 250 mu m, surface area about 0.2 mm(2). The conclusion is that the membrane is not in a genuine steady-state but rather the membrane changes spontaneously between several characteristic modes, There are periods of pseudo-steady-state in which the membrane voltage is rather stable in the range between -60 and -90 mV over about 1 h, and stable resistances can be found between 0.1 and 1.0 M Ohm. Dynamic stages are also characteristic: various types of oscillations (sinusoidal, saw-tooth and complex non-linear) with parallel and antiparallel phase relations between voltage and resistance, as well as transient voltage excursions down to -165 mV, revealing the operation of an electrogenic pump. The observed phenomena may be interpreted in terms of an electrical equivalent circuit with three parallel limbs: an electrogenic pump with a linear conductance, a K+ pathway with saturating currents of about -400 and +50 nA, and a linear Cl- conductance, each with a stable electromotive force and a variable proportion of activity.
引用
收藏
页码:445 / 452
页数:8
相关论文
共 18 条
[1]  
ANDERSON RA, 1991, PROVASOLIGUILLARD CT
[2]   Repetitive Ca2+ spikes in a unicellular green alga [J].
Bauer, CS ;
Plieth, C ;
Hansen, UP ;
Sattelmacher, B ;
Simonis, W ;
Schonknecht, G .
FEBS LETTERS, 1997, 405 (03) :390-393
[3]  
Blatt M. R., 1991, METHODS PLANT BIOCH, P281
[4]   Electric impedance of the squid giant axon during activity [J].
Cole, KS ;
Curtis, HJ .
JOURNAL OF GENERAL PHYSIOLOGY, 1939, 22 (05) :649-670
[5]   IONIC RELATIONS OF MARINE ALGAE .I. GRIFFITHSIA - MEMBRANE ELECTRICAL PROPERTIES [J].
FINDLAY, GP ;
HOPE, AB ;
WILLIAMS, EJ .
AUSTRALIAN JOURNAL OF BIOLOGICAL SCIENCES, 1969, 22 (05) :1163-&
[6]  
GRADMANN D, 1993, J MEMBRANE BIOL, V136, P327
[7]   MEMBRANE VOLTAGE OF MARINE-PHYTOPLANKTON, MEASURED IN THE DIATOM COSCINODISCUS-RADIATUS [J].
GRADMANN, D ;
BOYD, CM .
MARINE BIOLOGY, 1995, 123 (04) :645-650
[8]   Electrophysiology of the marine diatom Coscinodiscus wailesii -: II.: Potassium currents [J].
Gradmann, D ;
Boyd, CM .
JOURNAL OF EXPERIMENTAL BOTANY, 1999, 50 (333) :453-459
[9]   ANALOG CIRCUIT OF ACETABULARIA MEMBRANE [J].
GRADMANN, D .
JOURNAL OF MEMBRANE BIOLOGY, 1975, 25 (1-2) :183-208
[10]   STUDIES OF MARINE PLANKTONIC DIATOMS .1. CYCLOTELLA NANA HUSTEDT, AND DETONULA CONFERVACEA (CLEVE) GRAN [J].
GUILLARD, RR ;
RYTHER, JH .
CANADIAN JOURNAL OF MICROBIOLOGY, 1962, 8 (02) :229-&