%0 Journal Article
%T Immuno-electron microscopic quantification of the fucoxanthin chlorophyll a/c binding polypeptides Fcp2, Fcp4, and Fcp6 of Cyclotella cryptica grown under low- and high-light intensities
%A Becker
%A Frank
%A Rhiel
%A Erhard
%J International Microbiology
%D 2006
%I Viguera Editores, S.L.
%X the diatom cyclotella cryptica was grown under low- and high-intensity white light of 50 and 500 ¦Ìmol photons m-2 s-1, respectively. western immunoblotting showed that the diatom adapted its light-harvesting apparatus, giving rise to different amounts of distinct fucoxanthin chlorophyll a/c binding polypeptides (fcp). the amount of fcp2 was approximately two-fold higher under low-light than under high-light conditions, whereas the amount of fcp6 increased four- to five-fold under high-light conditions. for fcp4, no significant differences were detected in response to either light regime. cells of cyclotella grown under high- and low-light intensity were subjected to immunoelectron microscopy. quantification of the gold label, expressed as gold particles per ¦Ìm2, confirmed the results obtained by western immunoblotting. exposure to low light resulted in the detection of approximately six times more fcp2-bound gold particles per ¦Ìm2 in thylakoid membranes, whereas in cells grown under high light the number of fcp6-bound gold particles increased ten-fold. for fcp4, similar amounts of gold particles per ¦Ìm2 were counted under the two light regimes. these immunocytochemical results confirmed molecular data derived from phylogenetic analyses of the sequences of genes encoding fucoxanthin chlorophyll a/c binding polypeptides (fcp genes) and from measurements of steady-state fcp mrna concentrations. the results show that fcp2 and fcp6 accumulate under low- and high-light intensity, respectively, whereas fcp4 seems to be constitutively synthesized.
%K cyclotella
%K bacillariophyceae
%K photosynthesis
%K light-harvesting complexes
%K immunogold-labeling electron microscopy.
%U http://scielo.isciii.es/scielo.php?script=sci_abstract&pid=S1139-67092006000100004&lng=en&nrm=iso&tlng=en