Fig. 6. Cultured embryonic chick cardiomyocytes double-stained for (A,E) -actinin and (B,F) N-RAP. (C,G) Composite images show both -actinin staining in red and N-RAP staining in green. (D,H) The multiplied products of the red and green channels emphasize regions containing both N-RAP and -actinin fluorescence intensity. (A-D) Arrowheads are adjacent to peripheral regions of punctate -actinin staining that are characteristic of premyofibrils forming near the cell membrane. N-RAP is found in these regions, but is not confined to the -actinin dots. (E-H) N-RAP is also concentrated in areas where more mature sarcomeres appear to be fusing laterally (arrows).