Nucleolar localization of endogenous EGR1.

<p>Imaging analysis. (A) Confocal images of EGR1 and fibrillarin (upper row) or EGR1 and B23 (lower row) in the nucleolus of HeLa cells. The images were obtained with a Leica SP2 and analyzed under HCX PL APO CS 63x. (B) Immunogold electron microscopy (EM) labeling of EGR1 in the fibrillar center of the nucleolus. Ultrathin sections of HeLa cells were embedded in Lowicryl K4M. (FC, Fibrillar center; DFC, Dense Fibrillar Component; GC, Granular Component. Arrow: labelling in the CF; arrowheads: labelling in the nucleoplasm).