Sialic Acid Residues, Filamentous Actin, and Nuclear DNA in a Rat Colon Tissue Sample
The rat colon tissue section illustrated in the digital image above was labeled with wheat germ agglutinin (WGA) conjugated to Texas Red. WGA, which selectively binds to N-acetylglucosamine and N-acetylneuraminic (sialic acid) residues, is well suited for staining the Golgi network in fixed cells and tissues since a number of proteins and lipids found in the Golgi apparatus are glycosylated. The specimen was also labeled with Alexa Fluor 488 conjugated to phalloidin (targeting F-actin) and Hoechst 33342 (targeting DNA in the nucleus). Images were recorded in grayscale with a 12-bit digital camera coupled to a Nikon Eclipse 80i microscope equipped with bandpass emission fluorescence filter optical blocks. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles.