Fig. 4. Zipcode- and A2RE-binding proteins are present in rat cortical neurons and glial cells. Sections of cortex of 15-day-old rats were stained for KSRP (A,B red) FBP (C,D red), hnRNP A2 (E,F red) and hnRNPs A1 (G red), B1 (H red), and A3 (I red) by immunoperoxidase (A,C,E) and immunofluorescence methods (B,D,F-I). Most neurons (arrows in A,C, E) and all white matter glia (arrowheads in A,C,E) were labeled for KSRP, FBP and hnRNP A2. Confocal microscopy of sections double-labeled with oligodendrocyte markers CC1 (green in B,D, which show regions of white matter) and CNP (green in F-I, which show cortical grey matter) detected KSRP, FBP, hnRNP A2 and hnRNP A3 in these cells (arrows). hnRNP A1 was not detected in oligodendrocytes (G, arrowhead), and many were also B1-negative (H, arrowhead). wm and gm: white and grey matter. Bars, 100 µm for (A,C,E) and 25 µm for other images.