Figure 6

ELP-1 localizes to body wall muscle in hermaphrodites. (A) Near the muscle cell membrane, ELP-1::GFP is prominent in lines (small arrows) oriented with the longitudinal axis of the cell. ELP-1::GFP is also associated with an array of fluorescent filaments (jagged arrow). (B) Affinity-purified antibodies against ELP-1 also stain a linear array near the cell surface. Bar represents 10 μm. Within these "lines" there often is a repeating unit of fluorescence that is apparent in both transgenic animals (C) and in antibody-stained animals (D). Bar represents 2.5 μm. (E) Dense bodies (arrowheads) are shown at the muscle cell surface by phase contrast microscopy. ELP-1::GFP expression was examined via fluorescence light microscopy (F) and the two images taken at the same focal plane were overlaid in Panel G. Bar represents 1 μm. Muscle cells that were double-stained with antibodies against ELP-1 (H, J) and PAT-3/β-integrin (MH25) (I, and J) show overlapping staining patterns. The integrin puncta are superimposed upon the more linear staining pattern of ELP-1. When the membrane is removed by the freeze-cracking procedure (outlined in white in panel J), integrin is lost and the ELP-1 antigen remains. Bar represents 10 μm.