Yeast cells of Candida albicans which had been attached to polylysine-coated microscope slides were induced to form buds or germ tubes in the presence of external electrical fields. The sites of budding and germ tube formation and the growth of germ tubes and hyphal branches were polarized preferentially towards the cathode. Buds were not converted to pseudohyphae or germ tubes by the field and the field had no effect on the positioning of nuclei or septa in the yeast cell or germ tube. Buds were less polarized than germ tubes at any given applied voltage. The polarization of buds reached a peak at an electrical field of 12 m V per cell. Polarization of germ tubes was biphasic, increasing rapidly with increasing field strengths up to 5 mV per cell, and then more slowly in stronger fields. An electrical field was only required for a fraction of the time taken for germ tubes to start to form, so cells retained a memory of experiencing an electrical field which influenced the selection of sites of evagination. Increasing the electrical field delayed the time of germ tube evagination and inhibited the rate of germ tube extension. Unlike previous findings with other filamentous fungi, germ tubes grew unidirectionally towards the cathode for extended periods and did not deviate to a perpendicular orientation. This result suggests that the septal pore of the filamentous form may have high electrical resistance and would act as an effective barrier to solute transport between intercalary compartments.
CooperM. S.,
SchliwaM.1986; Transmembrane Ca2+ fluxes in the forward and reversed galvanotaxis of fish epidermal cells. In Ionic Currents in Development(Proceedings of a Satellite Meeting to the 10th International Congress of the International Society of Developmental Biologists, University of California, Los Angeles), pp 311–318NuccitelliR.
Edited by New York: Alan R. Liss;
De VriesS. C.,
WesselsJ.G.H.1982; Polarized outgrowth of hyphae by constant electrical fields during reversion of Schizophyllum commune protoplasts. Experimental Mycology 6:95–98
GowN.A.R.1987; Polarity and branching in fungi induced by electrical fields. In Spatial Organization in Eukaryotic Microbes (Special Publications of the Society for General Microbiology,vol.23) pp 25–41PooleR. K.,
TrinciA. P. J.
Edited by Oxford: IRL Press;
GowN.A.R.1988; Biochemical and biophysical aspects of dimorphism in Candida albicans
. In Proceedings of the 10th Congress for Human and Animal Mycology, pp 73–77Torres-RodriguezJ. M.
Edited by Barcelona: J. R. Prous Science;
GowN.A.R.,
GoodayG. W.1982; Growth kinetics and morphology of colonies of the filamentous form of Candida albicans
. Journal of General Microbiology 128:2187–2194
GowN.A.R.,
KropfD. L.,
HaroldF. M.1984; Growing hyphae of Achlya bisexualis generate a longitudinal pH gradient in the surrounding medium. Journal of General Microbiology 130:2967–2974
KropfD. L.,
LupaM.D.A.,
CaldwellJ. C.,
HaroldF. M.1983; Cell polarity: endogenous ion currents precede and predict branching in the water mold Achlya
. Science 220:1385–1387
LeeK. L.,
BuckleyH. R.,
CampbellC. C.1975; An amino acid liquid synthetic medium for the development of mycelial and yeast forms of Candida albicans
. Sabouraudia 13:148–153
McgillivrayA. M.,
GowN.A.R.1987; The transhyphal electrical current of Neurospora crassa is carried principally by protons. Journal of General Microbiology 133:2875–2881
OnumaE. K.,
HuiS.-W.1988; Electric field-directed cell shape changes, displacement, and cytoskeletal reorganization are calcium dependent. Journal of Cell Biology 106:2067–2075
SchreursW.J.A.,
HaroldF. M.1988; Transcellular proton current in Achlya bisexualis hyphae: relationship to polarized growth. Proceedings of the National Academy of Sciences of the United States of America 85:1534–1538
StaebellM.,
SollD. R.1985; Temporal and spatial differences in cell wall expansion during bud and mycelium formation in Candida albicans
. Journal of General Microbiology 131:1467–1480
StollbergJ.,
FraserS. E.1989; Electric field-induced redistribution of ACh receptors on cultured muscle cells: electromigration, diffusion, and aggregation. Biological Bulletin 176S:157–163
TakeuchiY.,
SchmidJ.,
CaldwellJ. C.,
HaroldF. M.1988; Transcellular ion currents and extension of Neurospora crassa hyphae. Journal of Membrane Biology 101:33–41
ThielR.,
SchreursW.J.A.,
HaroldF. M.1988; Transcellular ion currents during sporangium development in the water mould Achlya bisexualis
. Journal of General Microbiology 134:1089–1097