Actin localization at the tight junctions of invertebrate ciliated epithelia.
Indirect immunofluorescencc, rhodamine-phalloidin staining and immunoelectron microscopy performed with the on-grid postembedding immunostaining of Lowicryl K4M sections, were used to identify actin in the branchial epithelium of the lower chordate ascidians. The ciliated cells of these invertebrates present two distinct junctional patterns. One consists only of an extended tight junction whereas in the other the tight junction is accompanied by a prominent zonula adhaerens. Evidence is given of the localization of actin at the tight junction. The absence of reaction in the zonula adhaerens suggests that the definition of this junction in the model here presented must be reconsidered.
Dallai
R
R
Department of Evolutionary Biology, University of Siena, Siena, I-53100, Italy.
Burighel
P
P
Martinucci
G B
GB
Maci
R
R
Camatini
M
M