HeLa Cell Histones

Cy3 HYQ Bandpass Emission (Medium Bandwidth Excitation) Green Set

Fluorescence emission intensity from a culture of HeLa cells that were immunofluorescently labeled with primary anti-histone (pan) mouse monoclonal antibodies followed by goat anti-mouse Fab fragments conjugated to Alexa Fluor 546. The visible light absorption maximum of Alexa Fluor 546 is 556 nanometers and the emission maximum occurs at 573 nanometers (in the yellow region of the visible light spectrum). The primary antibody, produced from purified nuclear fractions of HeLa cells, binds specifically to an antigen determinant that is present on all five histone proteins (H1, H2A, H2B, H3, and H4). Note the strong yellow-orange fluorescence intensity from the cells undergoing mitosis, but the reduced emission intensity of interphase nuclei.