Representative immunocytochemistry images of 14-3-3 protein isoforms along and in the zonae pellucidae of cumulus-free oocytes isolated from ovaries of adult mice. The zona-intact cells were fixed in paraformaldehyde but not treated with detergent (see Methods). Paired images of an oocyte (left image is brightfield and right is immunofluorescence) indicate staining along the zona and/or the cell membrane for all isoforms except 14-3-3ζ. Note: the intent of this part of the study was not to examine the intracellular distribution of the isoforms (see Figure 3 for those experiments) since the cells were not permeabilized to permit complete antibody penetration; however, cells may be partially permeabilized by fixation accounting for the detection of intracellular proteins in some cells. (A,B) 14-3-3 β. (C,D) 14-3-3 γ. (E,F) 14-3-3 ε. (G,H) 14-3-3 ζ. (I,J) 14-3-3 η. (K,L) 14-3-3 τ. (M,N) 14-3-3σ. (O,P) Control image without primary antibody addition.