Biochemical Evidence for a Putative Inositol 1,3,4,5-Tetrakisphosphate Receptor in the Olfactory System of Atlantic Salmon (Salmo salar)

Figure 1

Initial screening of IP₃ and IP₄ binding sites in membrane fractions from salmon olfactory rosettes. The plasma membrane rich (PMR) fraction and a microsomal (MS) fraction were prepared from olfactory rosettes of Atlantic salmon. Specific binding of [³H]IP₃ was determined in incubations with 14 nM [³H]IP₃ in the presence and absence of excess unlabeled InsP₃. Specific binding of IP₄ to the PMR fraction is shown for comparison to IP₃. The concentration of [³H]IP₄ in the reaction mixture was also 14 nM.