Figure 3. Localization of acropsins 1 and 2 in A. palmata larvae.

Planulae were fixed, sectioned, probed with anti-acropsin antibodies as described in Materials and Methods. Laser confocal microscopy shows localization of the immunofluorescence (secondary antibody, Cy3, red), endogenous green fluorescence, and DAPI staining of the nuclei (blue). (A) Longitudinal section of the larva probed with anti-acropsin 1 antibody. Positive labeling of acropsin 1 (red) is observed in the larval gastrodermis. Image: snapshot (single z plane); objective = 40×; scale bar: 100 µm. (B) Transverse cross section labeled with anti-acropsin 2 antibody showing localization of acropsin 2 in solitary epithelial cells (red). Image: maximum projection; objective = 20×; scale bar: 100 µm. (C) Morphology of three acropsin 2-positive cells with proximal ends terminating in the mesoglea. Image: maximum projection; objective = 63× oil; scale bar: 10 µm. (D) Longitudinal section of the entire animal showing the predominantly aboral localization of acropsin 2-positive cells. Image: snapshot (single z plane); objective = 10×; scale bar: 100 µm.