Procion Yellow M-4rs Binding to Neuronal Membranes

Abstract

M-4R8, an intracellular neuronal marker, has been shown to bind covalently to the subcellular organelles of rat brain under physiologic conditions. Binding to purified proteins, nucleic acids and lipids also occurs under such conditions, the probable site of attachment being the primary amino group. Lipid membranes were highly impermeable to this dye. The fluorescence intensity of Procion Yellow M-4R8 was shown to be viscosity-dependent. These results are consistent with the behavior of the dye when it is used for mapping neurons.

Dynamic Behavior of Rod Photoreceptor Disks

“…The stained disks gradually move toward the pigment epithelium, and a few days after the injection, a length of unstained outer segment separates the stained disks from the base of the outer segment (Laties et al, 1976). A possible reconciliation of these observations with the ones reported here is that Procion Yellow binds covalently to subcellular organelles and proteins with the probable site of attachment being the amino group (Flanagan et al, 1974). In this case, the observed Procion Yellow staining of the basal disks would be due to covalent binding to proteins (mostly rhodopsin), and the result would be consistent with the one reported here for labeling with rhodamine green succinimidyl ester.…”