l-Alanine binding sites and Na + , K + -ATPase in cilia and other membrane fractions from olfactory rosettes of Atlantic salmon

• Published in: Comparative Biochemistry and Physiology Part B: Comparative Biochemistry
• Main Authors: Lo, Ying Har, Bradley, Terence M., Rhoads, Dennis E.
• Format: Text
• Language: unknown
• Published: DigitalCommons@URI 1991
• Subjects: Atlantic salmon; Salmo salar
• Online Access: https://digitalcommons.uri.edu/favs_facpubs/144; https://doi.org/10.1016/0305-0491(91)90317-7

1. 1. Membrane fractions were obtained from homogenates of olfactory rosettes from Atlantic salmon (Salmo salar) or from isolated olfactory cilia and homogenates of deciliated olfactory rosettes. 2. 2.|Specific binding of l-[3H]alanine was saturable, high-affinity, and effectively inhibited by l-threonine, l-serine and l-alanine but not by l-lysine or l-glutamic acid. Comparable results were obtained with l[3H]serine except for the presence of a second, lower affinity, binding site for l-alanine but not l-serine. 3. 3. Specific binding of l[3H]alanine was inhibited by low concentrations of mercury ion, acidic pH, and high concentrations of cadmium, copper or zinc ions. Aluminum had no effect. 4. 4. Specific binding sites for l-alanine were present in membranes from isolated cilia at a level 2-fold that of membranes prepared from the deciliated rosette. 5. 5. Ouabain sensitive Na+, K+-ATPase activity was also determined in cilia preparations. This enzyme was present in cilia at a level approximately 3-fold that of membranes prepared from the deciliated rosette. 6. 6.|The results are consistent with the presence of an olfactory alanine receptor in S. salar with binding characteristics similar to those of a variety of other fish species and with a localization on olfactory cilia as well as non-ciliated receptor cell membranes. © 1991.